Vascular Plants

Includes all flowering plants, conifers, ferns and fern-allies.


Browse by scientific name:

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Scientific names beginning with P:
Packera bolanderiBolander's groundsel
Distribution: Occurring west of the Cascades crest in southwestern Washington and in the Columbia River Gorge; southern Washington to California.
Habitat: Moist, rocky woodlands, banks, bluffs, and beaches, from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
var. harfordii – Harford's groundsel, Harford's ragwort
Packera canawoolly groundsel
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the northern Great Plains.
Habitat: Dry, open, often rocky places, from the foothills to alpine meadows.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Packera conterminadwarf arctic butterweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Washington, east to Alberta and Montana.
Habitat: Exposed, rocky places in the alpine to occasionally the subalpine;
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Packera flettiiFlett's groundsel
Distribution: Occurring in the Olympics and Cascades mountains in Washington; Washington to Oregon.
Habitat: Open, rocky places in the alpine, occasionally at middle elevatins, especially on talus slopes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Packera indecorarayless mountain butterweed, elegant groundsel
Distribution: Occurring on both sides of the Cascades crest in northern Washington; Alaska to Washington, and also in California, east to Idaho, Montana, Wyoming, and in the Great Lakes Region, also east across Canada to the Atlantic Coast.
Habitat: Damp meadows to stream banks and moist woodlands, from the valleys to the subalpine.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Packera macouniiPuget butterweed, long-rayed groundsel, Macoun's groundsel, Siskiyou Mountain ragwort
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California.
Habitat: Open woods and dry, open places at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Packera pauciflorarayless alpine butterweed, rayless alpine groundsel
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to northern Washington, disjunct in California and northwest Wyoming, east to Northwest Territory and Alberta, also in eastern Canada.
Habitat: Alpine and subalpine meadows and moist cliffs.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Packera pauperculaCanadian butterweed, balsam groundsel
Distribution: Occurring east of the Cascades crest in Washington British Columbia to Washington, east to the Rocky Mountains, northern Great Plains, and eastern North America.
Habitat: Meadows, moist cilffs and woods, from the foothills to middle elevations in the mountains.
Origin: Native
Flowers: May-October
Growth Duration: Perennial
Packera porteriPorter's groundsel
Distribution: Reported east of the Cascades crest in Okanogan County in Washington; Washington and Oregon, also occurring in Colorado.
Habitat: Talus slopes in the alpine.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Packera pseudaureastreambank butterweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, the Rocky Mountains, northern Great Plains, and central U.S.
Habitat: Wet meadows, stream banks and moist woodlands from middle elevations to the sublpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. pseudaurea – stream bank butterweed, falsegold groundsel
Packera streptanthifoliaRocky Mountain butterweed, cleftleaf groundsel, Rocky Mountain groundsel
Distribution: Occurring on both sides of the Cascades crest in Washington; Yukon Territory to California, east to the Rocky Mountains and Sasketchewan.
Habitat: Moist to moderately dry open areas and forest, from middle elevations to the subalpine.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Packera subnudaalpine meadow butterweed, few-leaved groundsel
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Alberta, Montana, and Wyoming.
Habitat: Wet meadows in the subalpine and alpine.
Origin: Native
Flowers: July-September.
Growth Duration: Perennial
var. subnuda – cleftleaf groundsel
Paeonia browniibrown's peony, western peony
Distribution: Occurring east of the Cascades crest in Washington; central Washington to California, east to Montana and Utah.
Habitat: Sagebrush deserts to ponderosa pine forest opening and edges.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Panicum capillarewitchgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Moist and irrigated areas, along streams and around ponds.
Origin: Native
Flowers: June-September
Growth Duration: Annual
ssp. capillare – common panicgrass, witchgrass
Panicum dichotomiflorumfall panicum
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlanitc Coast.
Habitat: Disturbed, often wet sites including stream banks and roadsides.
Origin: Introduced from eastern and central Washington
Flowers: May-September
Growth Duration: Annual, Perennial
ssp. dichotomiflorum – fall panicum, western witchgrass
Panicum giblinianum
Origin: Native
Panicum miliaceummillet
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Abandoned fields, roadsides, waste ground.
Origin: Introduced from Asia
Flowers: July-September
Growth Duration: Annual
ssp. miliaceum – broomcorn, hog millet, panic millet, proso millet
ssp. ruderale – broomcorn, hog millet, panic millet
Panicum virgata
Origin: Introduced from central and eastern North America
Growth Duration: Perennial
Panicum virgatum
Distribution: Occurring east of the Cascades crest in Washington; occurring in scattered locations near Portland, OR and Boise, ID, otherwise east of the Rocky Mountains in central and eastern North America, where native.
Habitat: Roadsides, fields, and other disturbed areas.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Papaver argemonelong prickly-head poppy
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to Oregon, east to Idaho.
Habitat: Fields, roadsides, wasteltots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: May-June
Growth Duration: Annual
Papaver dubiumlong-headed poppy
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Oregon east to Idaho; also in the central U.S. and eastern North America.
Habitat: Fields, dunes, marshy areas, roadsides, wastelots, and other disturbed sites.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Annual
Papaver rhoeascorn poppy
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across much of North America to the Atlantic Coast.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Annual
Papaver somniferumopium poppy
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across various parts of North America to the Atlantic Coast.
Habitat: Waste areas, roadsides, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Annual
Parameconopsis cambricaWelsh poppy
Distribution: Occurring west of the Cascades crest in Washington; southern British Columbia to Washington, perhaps introduced elsewhere.
Habitat: Forest edges where disturbed.
Origin: Introduced from Europe
Flowers: May-June
Growth Duration: Biennial, Perennial
Parapholis incurvasicklegrass
Distribution: Occurring west of the Cascades crest in Washington; southern British Columbia to California, also in the southeastern U.S. and Great Lakes region.
Habitat: Mostly coastal, along beaches.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Annual
Parietaria judiacapellitory-of-the-wall
Origin: Introduced from Africa and Eurasia
Growth Duration: Perennial
Parietaria pensylvanicaPennsylvania pellitory
Distribution: Occurring east of the Cascades crest in Washington; Yukon Territory south to California, east across southern Canada and the U.S. to the Atlantic Coast.
Habitat: Woods to shaded banks, beneath ledges of large rocks, from low to middle elevations.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Parnassia cirrataCascade grass-of-Parnassus
Distribution: Occurring in the Columbia River Gorge in Washington; Columbia River Gorge to California, east to Nevada and Idaho.
Habitat: Bogs, stream banks, and wet meadows, montane to alpine.
Origin: Native
Growth Duration: Perennial
var. intermedia – Cascade grass-of-Parnassus
Parnassia fimbriatafringed grass-of-Parnassus
Distribution: Occurring on both sides of the Cascades in Washington; Alaska to California, east to Alberta, Montana and New Mexico.
Habitat: Bogs, stream banks and wet meadows, mid- to high elevations in the mountains.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Parnassia kotzebueiKotzebue's grass-of-Parnassus
Distribution: Occurring east of the Cascades crest, where known only from Okanogan and Chelan counties in Washington; Alaska to Chelan County, WA, east to the Rocky Mountains, further east across Canada to the Atlantic Coast.
Habitat: Moist subalpine meadows, cliff faces, and ledges, often in boggy soil.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Parnassia palustrisgrass-of-Parnassus, northern grass-of-Parnassus
Distribution: Occurring on both sides of the Casades crest in Washington; Alaska to California, east to the northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Arctic tundra to moist, shaded areas in the mountains, where usually along streams or around springs.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Parnassia parviflorasmall-flowered grass-of-Parnassus
Distribution: Occurring east of the Cascades crest in northeastern Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Bogs, stream banks, and wet meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Parthenocissus vitaceafalse Virginia creeper, thicket creeper
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east across the U.S. to the mid-Atlantic states, where native.
Habitat: Disturbed open areas and forest edge, often where moist, from low to middle elevations.
Origin: Introduced from the central and eastern U.S.
Flowers: May-July
Growth Duration: Perennial
Pascopyrum smithiiwestern wheatgrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to California, east to the Great Plains.
Habitat: Sagebrush, prairie, and mesic alkaline meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Paspalum distichumknotgrass, Thompsongrass
Distribution: Occurring chiefly along the lower Columbia River corridor in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Along ditches and streams where the soil is moist much of the season.
Origin: Native
Flowers: August-October
Growth Duration: Perennial
Pastinaca sativacommon parsnip, wild parsnip
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed sites at low elevations.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Biennial
Paulownia tomentosaprincess tree
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to Oregon; also Great Lakes region to Texas, east to the Atlantic Coast.
Habitat: Disturbed, open areas often relatively close to sites where trees are being cultivated.
Origin: Introduced from Eurasia
Flowers: May-June
Growth Duration: Perennial
Paxistima myrsinitesOregon boxleaf
Distribution: Widely distributed on both sides of the Cascades in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Sea-level to alpine in forest understory, forest edge; balds, and rocky openings.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Pectiantia pentandrafive-stamen bishop's-cap, alpine mitrewort
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska south to California, east to the Rocky Mountains of Canada and the U.S.
Habitat: Wet meadows and moist woods, especially along streams, lowlands to mid-elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pectocarya penicillatashortleaf combseed, winged pectocarya
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to Baja California, east to Idaho and Utah.
Habitat: Dry, open areas, often in sandy soil and among sagebrush, at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Pectocarya setosabristly combseed
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho, Utah, and New Mexico.
Habitat: Open areas in sagebrush-steppe habitat.
Origin: Native
Flowers: May-June
Growth Duration: Annual
Pedicularis bracteosabracted lousewort
Distribution: Widely distributed throughout the mountainous areas of Washington; British Columbia south to California, east to Montana, Colorado and New Mexico.
Habitat: Common in open forests at moderate to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. atrosanguinea – bracted lousewort
var. bracteosa – bracted lousewort
var. flavida – bracted lousewort
var. latifolia – bracted lousewort
var. pachyrhiza – bracted lousewort
var. siifolia – bracted lousewort
Pedicularis contortawhite coiled-beak lousewort
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana and Wyoming.
Habitat: Open wooded slopes and drier meadows at high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. contorta – white-coiled beak lousewort
Pedicularis groenlandicabull elephant's-head
Distribution: Occurring on both sides of the Cascades crest and in the Olympic Mountains in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Seeps, lake shores, wet meadows, and other wet areas from middle elevations to the subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pedicularis ornithorhynchosduck's-bill, bird's-beak lousewort
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Washington.
Habitat: Subalpine and alpine meadows.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Pedicularis pulchellapretty lousewort
Distribution: Occurring east of the Cascades crest, where known only from Chelan County; also occurring in southwestern Montana, where previously thought to be endemic.
Habitat: Alpine slopes.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Pedicularis racemosaleafy lousewort, sickletop lousewort
Distribution: Widely distributed across Washington; British Columbia south to California, east to Montana, Colorado and New Mexico.
Habitat: Coniferous forests at mid-elevations in the mountains.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
var. alba – sickletop lousewort
var. racemosa – sickletop lousewort
Pedicularis rainierensisMt. Rainier lousewort
Distribution: Endemic to Mount Rainier National Park area in Washington.
Habitat: Moist alpine meadows.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Pediocactus nigrispinusbasalt cactus, dark-spine ball cactus, snowball cactus
Distribution: Occurring east of the Cascades crest in central Washington; central Washington to southeastern Oregon, east to western Idaho.
Habitat: Lowland to montane sagebrush desert, grasslands, and coniferous forests.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
ssp. nigrispinus – dark-spine ball cactus
Peganum harmalaAfrican rue
Origin: Introduced
Flowers: June - August
Growth Duration: Perennial
Pellaea brachypteraSierran cliffbrake
Distribution: Occurring east of the Cascades crest, where disjunct in Chelan County; otherwise, Lane County, OR to the Sierra Mountains of California.
Habitat: Dry, rocky slopes from lowlands to montane.
Origin: Native
Spores: May-July
Growth Duration: Perennial
Pellaea breweriBrewer's cliffbrake
Distribution: Occurring on both sides of the Cascades crest In Washington; southern British Columbia to California, east to western Montana, Utah, and Colorado.
Habitat: Talus slopes, cliff crevices and other rocky places, foothills to timberline.
Origin: Native
Spores: June-September
Growth Duration: Perennial
Pellaea gastonyiGastony's cliff-brake
Distribution: Occurring east of the Cascades crest in northeastern Washington; in scattered locations including southeastern British Columbia, Sasketchewan, South Dakota, and Missouri.
Habitat: cliff crevices, usually on limestone, montane to subalpine.
Origin: Native
Growth Duration: Perennial
Pellaea glabellasmooth cliff-brake
Distribution: Occurring east of the Cascades crest in Washington; central British Columbia to Washington, east to the Rocky Mountains, and eastward to central and eastern North America.
Habitat: Cliff crevices, limestone or basalt, from lowlands to the montane.
Origin: Native
Growth Duration: Perennial
ssp. occidentalis – western smooth cliff-brake
ssp. simplex – simple cliff-brake
Peltandra virginicaarrow arum, tuckahoe
Distribution: Occurring in scattered locations west of the Cascades crest in Washington; western Washington to northwestern Oregon, otherwise eastern North America where native.
Habitat: Shallow water of slow moving water, ponds, and lake shores at low elevation.
Origin: Introduced from eastern North America
Flowers: June-August
Growth Duration: Perennial
Penstemon acuminatussand dune penstemon, sharp-leaved penstemon
Distribution: Occurring east of the Cascades crest from Chelan and Douglas counties south along the Columbia River to Klickitat County; central Washington to north-central Oregon, also from southeastern Oregon to northern Nevada, east to southwestern Idaho.
Habitat: Dry, open, sandy places at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
var. acuminatus – sand dune beardtongue, sand dune penstemon, sharp-leaved penstemon
Penstemon attenuatustaper-leaved beardtongue, sulphur penstemon, taper-leaved penstemon
Distribution: Occurring east of the Cascades crest in Washington; southeastern British Columbia to northeastern Oregon, east to western Montana and Wyoming.
Habitat: Dry to moist meadows and woodland slopes from the lowlands to the subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. attenuatus – taper-leaved beardtongue, sulphur penstemon, taper-leaved penstemon
Penstemon barrettiaeBarrett's beardtongue
Distribution: Occurring in the east end of the Columbia River Gorge in Washington; south-central Washington to adjacent north-central Oregon.
Habitat: Woodland openings and rocky slopes at low elevations.
Origin: Native
Flowers: April-May
Growth Duration: Perennial
Penstemon cardwelliiCardwell's beardtongue
Distribution: Occurring west of the Cascades crest in Washington; southwestern Washington to southwestern Oregon.
Habitat: Open or wooded summits or slopes at middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Penstemon cinereusgray beardtongue
Distribution: Occurring east of the Cascades crest in Washington; central Washington to northeastern California and northwestern Nevada.
Habitat: Open areas at low to middle elevations in loamy or igneous rocky or gravelly soils.
Origin: Native
Flowers: April-June
ssp. cinereus – gray beardtongue
ssp. foliatus – leafy gray beardtongue
Penstemon confertuslesser yellow beardtongue
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to Oregon, east to Alberta, Idaho and Montana.
Habitat: Coniferous forest openings and open slopes from low to middle elevations.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Penstemon davidsoniiDavidson's penstemon
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California and Nevada.
Habitat: Open, rocky areas, from middle to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. davidsonii – Davidson's beardtongue
var. menziesii – Davidson's beardtongue
Penstemon deustushot-rock penstemon
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to Montana and Utah.
Habitat: Open rocky roadsides, hillsides, and rock outcrops, sometimes in dry meadows, lowland to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. deustus – hot-rock penstemon
var. variabilis – hotrock penstemon, scabland penstemon, scorched penstemon
Penstemon ellipticusrockvine beardtongue
Distribution: Occurring east of the Cascades crest in northeastern Washington; southeastern British Columbia to northeastern Washington, east to Alberta and Montana.
Habitat: Rocky places at high elevations in the mountains, often on cliffs, ledges, or in rock crevices.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Penstemon eriantheruscrested-tongue penstemon, fuzzy-tongue penstemon
Distribution: Occurring east of the Cascades crest chiefly in central and northeastern Washington; southeastern British Columbia to Oregon, east to the northern Great Plains.
Habitat: Dry, open places in the valleys, plains and foothills, sometimes ascending to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. eriantherus – fuzzy-tongue penstemon
var. whitedii – Whited's fuzzy-tongue penstemon
Penstemon euglaucusglaucous beardtongue
Distribution: Occurring in the Cascades Range in Washington from Mt Adams south; Washington to central Oregon.
Habitat: Dry, sandy, open or sparsely wooded slopes at moderate elevations to subalpine meadows.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Penstemon fruticosusbush penstemon, shrubby penstemon
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to Oregon, east to Alberta, Montana and Wyoming.
Habitat: Common in rocky, open or wooded areas, foothills to rather high elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. fruticosus – shrubby penstemon
var. scouleri – shrubby penstemon
var. serratus – shrubby penstemon
Penstemon gairdneriGairdner's penstemon
Distribution: Occurring east of the Cascades crest in Washington; Washington to Oregon, east to Idaho.
Habitat: Dry, open sagebrush desert and scablands, low to moderate elevations in the mountains.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
var. gairdneri – Gairdner's penstemon
Penstemon glandulosusglandular penstemon
Distribution: Occurring east of the Cascades crest in Washington; central Washington to north-central Oregon, and from southeastern Washington to eastern Oregon, east to Idaho.
Habitat: Open, often rocky hillsides and banks in the foothills, valleys, and lower mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. chelanensis – sticky-stem penstemon
var. glandulosus – sticky-stem penstemon
Penstemon hesperiustall beardtongue
Distribution: Occurring west of the Cascades crest in southwestern Washington; narrowly distributed from southwestern Washington to northwestern Oregon.
Habitat: Moist, lowland meadows and stream banks.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Penstemon lyalliiLyall's penstemon
Distribution: Reported from east of the Cascades crest in northeastern Washington, but no specimens seen; southeastern British Columbia to northeastern Washington, east to Alberta, northern Idaho, and western Montana.
Habitat: Rocky slopes, talus, and rock outcrops.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Penstemon ovatusegg-leaf beardtongue, broad-leaved penstemon
Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to Oregon.
Habitat: Open woods below 3000 feet in elevation.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Penstemon pennellianusBlue Mountains beardtongue, Pennell's beardtongue
Distribution: Occurring east of the Cascades crest in the Blue Mountains of southeastern Washington; southeastern Washington to the Blue Mountains in adjacent northeastern Oregon.
Habitat: Open, gravelly and sandy slopes and ridges, sometimes associated with ponderosa pine forest openings, at middle elevations.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Penstemon procerussmall-flowered penstemon
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Moist forest openings at moderate elevations to rocky slopes at high elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. procerus – small-flowered penstemon
var. tolmiei – small-flowered penstemon
Penstemon pruinosusChelan beardtongue
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to Washington.
Habitat: Open, rocky places from the valleys and plains to moderate elevations in the mountains, and in the scablands in Washington.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Penstemon richardsoniiRichardson's penstemon
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to north-central and northeast Oregon.
Habitat: Cliff crevices and other dry, rocky places at low to moderate elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. richardsonii – Richardson's penstemon
Penstemon rupicolacliff beardtongue, rock penstemon
Distribution: Occurring on both sides of the Cascades crest and in the Columbia River Gorge in Washington; Washington to California.
Habitat: Rock cliffs and rocky slopes from middle elevations in the mountains to the alpine.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Penstemon rydbergiiRydberg's beardtongue
Distribution: Occurring east of the Cascades in Washington; Washington to California, east to the Rocky Mountains.
Habitat: Meadows and moist, open slopes, occasionally on drier slopes with sagebrush, chiefly in the foothills and at moderate elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Penstemon serrulatusCascade beardtongue, coast penstemon
Distribution: Occurring on both sides of the Cascades crest and in the Olympic Mountains in Washington; southern British Columbia to Oregon.
Habitat: Moist to wet meadows and forest openings, from low elevations to the subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Penstemon speciosusroyal beardtongue, showy penstemon
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Nevada and Utah.
Habitat: Dry, open or sparsely wooded areas, often with sagebrush, juniper or ponderosa pine, mostly in the lowlands and foothills.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Penstemon subserratusfine-toothed beardtongue, subserrate beardtongue
Distribution: Occurring chiefly east of the Cascades crest in Washington; north-central Washington to north-central Oregon.
Habitat: Open ponderosa pine forest and clearings at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Penstemon triphylluswhorled beardtongue
Distribution: Occurring chiefly east of the Cascades crest in the southeastern area of Washington; Southeast Washington south to adjacent Oregon and east to adjacent Idaho.
Habitat: Cliff crevices and dry, rocky banks and slopes at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. triphyllus – whorled beardtongue, whorled penstemon
Penstemon venustuselegant beardtongue, Blue Mountain penstemon
Distribution: Occurring east of the Cascades crest in Washington, where introduced in central Washington and native to the Blue Mountains region in southeastern Washington; Washington to California, east to Idaho and Utah.
Habitat: Open, rocky slopes, from the foothills to moderate elevations in the mountains.
Origin: Native and Introduced
Flowers: May-August
Growth Duration: Perennial
Penstemon washingtonensisWashington beardtongue
Distribution: Occurring east of the Cascades crest, where endemic to Chelan and Okanogan in Washington.
Habitat: From open slopes and flats at moderate elevations to alpine meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Penstemon wilcoxiiWilcox's beardtongue
Distribution: Occurring east of the Cascades crest in eastern Washington; Washington to Oregon, east to Montana.
Habitat: Open or often wooded, sometimes in rocky places, from the foothills to moderate elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Pentaglottis sempervirensgreen alkanet
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to California.
Habitat: Disturbed soil in forest edge and other shaded areas.
Origin: Introduced from Europe
Flowers: April-July
Growth Duration: Perennial
Pentagramma triangularisgold fern, gold-back fern
Distribution: Occurring mostly west of the Cascades crest and in the Columbia River Gorge in Washington; Vancouver Island to Baja California, east to southwestern Washington and adjacent Idaho.
Habitat: Rock crevices and open, rocky slopes in the valleys and foothills
Origin: Native
Growth Duration: Perennial
Penthorum sedoidesditch stonecrop
Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern British Columbia to northwestern Oregon.
Habitat: Cultivated cranberry bogs.
Origin: Introduced from eastern North America
Flowers: June-August
Growth Duration: Perennial
Perideridia montanamountain yampah
Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Woodland edge, balds, prairies, outcroppings, and vernally wet meadows from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Perideridia oreganaOregon yampah
Distribution: Occurring west of the Cascades crest in southwestern Washington; southern Washington to California.
Habitat: Moist to dry meadows and open slopes or flats, from low to moderate elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Perilla frutescens
Origin: Introduced
Persicaria amphibiawater smartweed
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: River, stream, lake, and pond margins in water to 2 meters deep to adjacent moist uplands.
Origin: Native
Flowers: July-October
Growth Duration: Perennial
Persicaria hydropipersmartweed, mild water-pepper
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Shores, swales, ditches, and disturbed ground.
Origin: Introduced from Europe
Flowers: July-September
Growth Duration: Annual
Persicaria hydropiperoideswater pepper, swamp smartweed
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to Mexico and South America, east across North America to the Atlantic coast.
Habitat: Moist to swampy areas, often growing in mud, from the lowlands to the lower mountain valleys.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Persicaria lapathifoliadock-leaf smartweed, pale smartweed, willow weed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Streambanks, pond and lakeshores and other wet places.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Persicaria maculosaheartweed, lady's-thumb, spotted lady's-thumb, redshank
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: A weedy species, usually on moist, cultivated or otherwise disturbed soil.
Origin: Introduced from Eurasia
Flowers: March-September
Growth Duration: Perennial
Persicaria punctatadotted knotweed, dotted smartweed, water smartweed
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Atlantic Coast.
Habitat: Lake and pond shores, marshes, and wet forests.
Origin: Native
Flowers: June-September
Growth Duration: Annual, Perennial
Persicaria wallichiigarden knotweed, Himalayan knotweed
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California; also in eastern North America.
Habitat: Waste areas, roadsides, and other disturbed areas where often where somewhat moist.
Origin: Introduced from eastern Asia
Flowers: July-October
Growth Duration: Perennial
var. wallichii – garden knotweed, Himalayan knotweed
Petasites frigidusalpine butterbur, sweet coltsfoot
Distribution: Occurring in forested and mountainous areas throughout Washington; Alaska to California, east across the northern half of North America to the Atlantic Coast; circumboreal.
Habitat: Meadows, swamps, and other wet places, from low elevations to the alpine.
Origin: Native
Flowers: March-August
Growth Duration: Perennial
var. frigidus – alpine butterbur, arctic butterbur, sweet coltsfoot
var. palmatus – western coltsfoot
var. sagittatus – arrowhead sweet coltsfoot, arrowleaf coltsfoot
var. ×vitifolius – hybrid coltsfoot, Wenatchee coltsfoot
Petasites japonicusJapanese sweet coltsfoot
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to Oregon.
Habitat: Forest edge, typically where moist and disturbed; generally escaping from cultivation.
Origin: Introduced from Asia
Flowers: June-September
Growth Duration: Perennial
Petrophytum caespitosumRocky Mountain rockmat
Distribution: Occurring east of the Cascades crest in southeastern Washington; southeastern Washington to California, east to Montana, Idaho, New Mexico, Texas, and South Dakota.
Habitat: Dry, limy or granite cliffs, ledges, talus, and rocky slopes, lowland to alpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. caespitosum – Rocky Mountain rockmat
Petrophytum cinerascensChelan rockmat
Distribution: Occurring east of the Cascades crest, where endemic to the Columbia River region of central Washington.
Habitat: Basaltic cliffs.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Petrophytum hendersoniiOlympic Mountain rockmat
Distribution: Occurring west of the Cascades crest, where endemic to the Olympic Mountains.
Habitat: Rocky cliffs and talus slopes at middle to high elevations.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Petroselinum crispumparsley
Distribution: Occurring in scattered locations west of the Cascades crest in Washington at low elevations, where escaping from nearby cultivation; Washington to California, east in scattered locations across the U.S. to the Atlantic Coast.
Habitat: Roadsides, balds, fields, ditches, wastelots, and other disturbed open areas at low elevations.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Biennial
Phacelia bolanderiBolander's phacelia, Bolander's scorpion-weed
Distribution: Occurring west of the Cascades crest in lowland southwestern Washington; Coos Bay, Oregon south along the coast to Sonoma County, California.
Habitat: Mostly on open, often unstable slopes at low elevations.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Phacelia frankliniiFranklin's scorpion-weed
Distribution: Occurring east of the Cascades crest in northeastern Washington; Yukon to northeastern Washington, east to western Montana and Wyoming, further east to the Great Lakes region.
Habitat: Talus and open areas at middle elevations in the mountains
Origin: Native
Flowers: June-July
Growth Duration: Annual, Biennial
Phacelia glanduliferasticky phacelia, glandular-hair scorpion-weed
Distribution: Occurring east of the Cascades crest in central Washington; Washington to California, east to Idaho, Nevada, Utah, and Wyoming.
Habitat: Open areas in sagebrush desert.
Origin: Native
Flowers: June
Growth Duration: Annual
Phacelia hastatasilverleaf phacelia, whiteleaf phacelia
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the northern Great Plains.
Habitat: Dry, open, often sandy areas, low to high elevations.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. compacta – silverleaf phacelia, whiteleaf phacelia
var. hastata – silverleaf phacelia, whiteleaf phacelia
var. leptosepala – narrow-sepal scorpion-weed
Phacelia heterophyllavarileaf phacelia, virgate phacelia
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Widespread in dry, open places from the foothills to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Biennial, Perennial
Phacelia humilislow phacelia
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Nevada.
Habitat: Moist to moderately dry soil at low to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Annual
var. humilis – low phacelia
Phacelia lentasticky scorpion-weed
Distribution: Occurring east of the Cascades crest in Washington, where endemic to Chelan and Douglas counties.
Habitat: Open rocky habitats, talus, rocky outcrops.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phacelia linearisthread-leaf phacelia, thread-leaf scorpion-weed
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Common in dry, open places in the foothills and plains to moderate elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Phacelia minutissimaleast phacelia, dwarf scorpion-weed
Distribution: Occurring east of the Cascades crest in Kittitas County in Washington; central Washington to northeastern Nevada, east to Idaho.
Habitat: Meadows and forest openings at middle elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Annual
Phacelia nemoralisshade phacelia, woodland phacelia
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; British Columbia to California.
Habitat: Thickets and woodlands, usually in fairly dry and shady areas, at low elevations.
Origin: Native
Flowers: April-July
Growth Duration: Biennial, Perennial
var. oregonensis – woodland phacelia
Phacelia proceratall scorpion-weed
Distribution: Occurring chiefly east of the Cascades crest in Washington; Washington to California, also in the Blue Mountains of northeast Oregon and east to adjacent west-central Idaho.
Habitat: Meadows, forest openings and edge, and lightly wooded slopes at middle elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Phacelia ramosissimabranched phacelia
Distribution: Occurring east of the Cascades crest in Washington; south-central British Columbia to California, east to southwestern Idaho and Arizona.
Habitat: Dry, open places in the plains and foothills, commonly on basaltic talus, ledges and cliffs.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. ramosissima – branched phacelia
Phacelia sericeasilky phacelia
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Open, often rocky areas, from middle elevations in the mountains to the alpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. sericea – silky phacelia
Phacelia tetrameradwarf phacelia, four-part yellow scorpion-weed
Distribution: Occurring east of the Cascades crest in central Washington; central Washington to California, east to Idaho, Wyoming and Utah.
Habitat: Alkaline flats and washes at low to middle elevations.
Origin: Native
Flowers: May-June
Growth Duration: Annual
Phalaris arundinaceareed canarygrass
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America, except for extreme southern U.S., to the Atlantic Coast.
Habitat: Stream banks, meadows, fields, roadsides, irrigation ditches, and other disturbed open places from low elevations to nearly the subalpine.
Origin: Introduced from Europe
Flowers: June-July
Growth Duration: Perennial
Phalaris canariensiscommon canary grass
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Disturbed ground, roadsides, shores, and lawns.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Annual
Phegopteris connectilisnarrow beech fern, northern fern
Distribution: Occurring west of the Cascades crest in Washington; Alaska to Washington and norttheastern Oregon, east across the northern U.S. and Canada to the Atlantic Coast; circumboreal.
Habitat: Cliff crevices and moist banks in wooded regions.
Origin: Native
Growth Duration: Perennial
Phemeranthus sediformisOkanogan fameflower
Distribution: Occurring east of the Cascades crest in north-central Washington; southern British Columbia to northern Washington.
Habitat: Rocky, exposed slopes and ledges at lower elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Phemeranthus spinescensspinescent fameflower, spiny fameflower
Distribution: Occurring east of the Cascades crest in Washington; north-central Washington to north-central Oregon.
Habitat: Rocky, basaltic outcrops and sagebrush scabland.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Philadelphus lewisiiLewis' mock orange
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Dry to moist, partially shaded to open areas from low to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Phleum alpinummountain timothy
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Great Plains, also in northeastern North America.
Habitat: Streambanks and meadows at higher elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Phleum pratensetimothy
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Disturbed areas, especially moist, open meadows, from coast to midmontane.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Perennial
ssp. pratense – common timothy
Phlox caespitosaclumped phlox, clustered phlox, stiff phlox, tufted phlox
Distribution: Occurring east of the Cascades crest in Washington; south-central British Columbia to south-central Washington, east to Idaho and Montana.
Habitat: Primarily in and near Ponderosa pine forest.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phlox colubrinaSnake River phlox
Distribution: Occurring east of the Cascades crest in the southeastern counties in Washington; southeastern Washington to adjacent northeastern Oregon and western Idaho.
Habitat: Dry, open slopes and cliffs.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phlox diffusaspreading phlox
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California.
Habitat: Open, often rocky areas, mid- to high elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Phlox hendersoniiHenderson's phlox
Distribution: Occurring in the Olympic Mountains and in the Cascades east of the crest in Washington; Washington to Oregon.
Habitat: Open, often rocky areas, mid- to high elevations in the mountains.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Phlox hoodiiHood's phlox
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Dry, open places in the plains and foothills, often in lithosol, occasionally to moderate elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
ssp. canescens – carpet phlox, Hood's phlox
Phlox longifolialong-leaf phlox
Distribution: Widely distributed east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Sagebrush desert to ponderosa pine forest openings, from low to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phlox multifloramany-flowered phlox
Distribution: Occurring east of the Cascades crest in the southeastern counties in Washington; southeastern Washington to northwestern Nevada, east to the Rocky Mountains.
Habitat: Ponderosa pine forest openings and open meadows from middle elevations to the subalpine.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Phlox solivagayeti phlox
Distribution: Occurring east of the Cascades crest, where endemic to the southeastern counties in Washington.
Habitat: Windswept, rocky soil of montane to subalpine ridgelines.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Phlox speciosashowy phlox
Distribution: Widely distributed east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Shrub-steppe, often with sagebrush, and in ponderosa pine forest openings.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phlox viscidasticky phlox
Distribution: Occurring east of the Cascades crest in southeastern Washington; southeastern Washington to northeastern Oregon, east to adjacent Idaho.
Habitat: Open areas in grasslands and ponderosa pine forest.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Phoenicaulis cheiranthoidesdaggerpod
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho and Nevada.
Habitat: Shrub-steppe and open ponderosa pine forests.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Photinia davidianaChinese redtip, stranvaesia
Distribution: Occurring west of the Cascades crest in lowland western Washington.
Habitat: Thickets, open forests, shores, rarely epiphytic
Origin: Introduced from China
Flowers: April-June
Growth Duration: Perennial
var. davidiana – Chinese redtip, stranvaesia
Phragmites australiscommon reed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Disturbed areas, including roadsides, often where wet or seasonally moist.
Origin: Native and introduced from Eurasia and northern Africa
Flowers: July-September
Growth Duration: Perennial
ssp. americanus – common reed
ssp. australis – common reed
Phyllodoce empetriformispink mountain-heath
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Montana, Wyoming, and Arizona.
Habitat: Rocky sites in high coniferous forests to alpine meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Phyllodoce glanduliflorayellow mountain-heath
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Oregon, east to Wyoming.
Habitat: Rocky sites in high coniferous forests to alpine meadows and seeps.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Phyllodoce ×intermediahybrid mountain-heath
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Yukon Territory to Oregon, east to Northwest Territory, Alberta, Montana, and Wyoming.
Habitat: Subalpine and alpine meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Phyllospadix scouleriScouler's surf-grass
Distribution: Occurring west of the Cascades crest along the coast of Washington where rocky; Alaska to California.
Habitat: Rocky intertidal and sub-tidal zones.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Phyllospadix serrulatustoothed surf-grass
Distribution: Occurring west of the Cascades crest along the rocky coastline of northwestern Washington; Alaska to Washington.
Habitat: On rocks in upper tidal to subtidal zones, rarely on deep clay substrates.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Phyllospadix torreyiTorrey's surf-grass
Distribution: Occurring west of the Cascades crest along the rocky coastline of northwestern Washington; British Columbia to California along the immediate coast.
Habitat: Rocky sub-tidal zone.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Physalis grisealow hairy ground cherry, strawberry-tomato
Distribution: Occurring on both sides of the Cascades crest in Washington; Washington to California, also in Utah; more widespread in the central and eastern U.S.
Habitat: Fields, roadsides, wastleots, and other disturbed areas.
Origin: Introduced from eastern North America
Flowers: July-September
Growth Duration: Annual
Physalis longifoliaground-cherry, long-leaved ground-cherry, wild tomatillo
Distribution: Occurring chiefly east of the Cascades in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Weed of cultivated fields and waste places.
Origin: Both native and introduced
Flowers: June-September
Growth Duration: Perennial
var. longifolia – ground-cherry, long-leaved, wild tomatillo
Physaria alpestrisalpine twinpod, Washington twinpod
Distribution: Occurring east of the Cascades crest in Washington, where endemic to Chelan, Kittitas and Yakima counties.
Habitat: Open rocky areas, scree and talus slopes, middle to high elevations in the mountains.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Physaria didymocarpacommon twinpod
Distribution: Occurring east of the Cascades crest in northeastern Washington; southeastern British Columbia to northeastern Washington, east to Alberta and Wyoming.
Habitat: Talus, gravel bars, outcrops, dry slopes, prairies, road cuts
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. didymocarpa – common twinpod
Physaria douglasiiColumbia bladderpod, Douglas' bladderpod
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to northern Oregon, east to northwestern Montana.
Habitat: Common in sagebrush desert, especially near or in juniper or ponderosa pine woodlands.
Origin: Native
Flowers: March-July
Growth Duration: Perennial
ssp. douglasii – Douglas's bladderpod
ssp. tuplashensis – White Bluffs bladderpod
Physaria geyeriGeyer's twinpod
Distribution: Occurring east of the Cascades crest in eastern Washington; eastern Washington to eastern Oregon, east to Idaho and Montana.
Habitat: Gravelly stream banks and hillsides.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
ssp. geyeri – double bladderpod, Geyer's twinpod bladderpod, Geyer's twinpod
Physaria occidentaliswestern bladderpod
Distribution: Occurring east of the Cascades crest in eastern Washington, where known from a historic (1899) population on Mt. Adams. Washington to California, east to Idaho, Utah, and Nevada.
Habitat: Open, rocky slopes at low to moderate elevations.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
ssp. occidentalis – western bladderpod
Physaria oregonaOregon twinpod
Distribution: Occurring east of the Cascades crest in southeastern Washington; Washington to Oregon, east to Idaho.
Habitat: Dry areas including rocky slopes, gravel banks, and stream shores.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Physocarpus capitatusPacific ninebark
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to Idaho.
Habitat: Moist woods and swamps in the lower mountains.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Physocarpus malvaceusmallow ninebark, mallow-leaf ninebark
Distribution: Occurring east of the Cascades crest in eastern Washington; British Columbia to Oregon and Nevada, east to Alberta, Montana, Wyoming, and Colorado.
Habitat: Canyons and hillsides, grasslands, ponderosa pine and Douglas-fir forest openings and edge.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Physostegia parviflorapurple dragonhead, western false dragonhead
Distribution: Occurring east of the Cascades crest and along the Columbia River in Washington; British Columbia to Oregon, east to the Rocky Mountains, Great Plains, and the central U.S.
Habitat: Shores of strams and lakes, marshes, and other low, wet places in the valleys and foothills.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Phyteuma scorzonerifoliumscorzonera-leaved rampion
Distribution: Known in Washington from a single population in King County, WA.
Habitat: Disturbed areas.
Origin: Introduced from Europe
Flowers: July-August
Growth Duration: Perennial
Phytolacca americanapigeonberry, pokeberry, pokeweed
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, where introduced; native to central and eastern North America.
Habitat: Roadsides, pastures, clearings, disturbed areas.
Origin: Introduced from central and eastern North America
Flowers: June-August
Growth Duration: Perennial
var. americana – pigeonberry, pokeberry, pokeweed
Picea ×albertianainterior spruce
Origin: Native
Picea engelmanniiEngelmann's spruce
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Moderate to high elevations in the mountains, mostly where somewhat moist.
Origin: Native
Cones: New cones from June-August
Growth Duration: Perennial
var. engelmannii – Engelmann spruce
Picea sitchensisSitka spruce
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California.
Habitat: Along the coast, from sea level up to about 2,000 feet in moist valleys.
Origin: Native
Cones: May-June
Growth Duration: Perennial
Picris hieracioideshawkweed ox-tongue
Distribution: Occurring in the Columbia River Gorge in Washington; British Columbia to Washington; also in eastern North America.
Origin: Introduced from Europe
Growth Duration: Biennial, Perennial
Pilularia americanaAmerican pillwort
Distribution: Occurring east of the Cascades in far eastern Washington; disjunct in eastern Washington, otherwise Oregon to California, also in the central and southeastern U.S.
Habitat: Shallow ponds, vernal pools, and reservoir margins.
Origin: Native
Spores: June-October
Growth Duration: Perennial
Pinguicula vulgariscommon butterwort
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, also in Montana; east across Canada to eastern North America; circumboreal.
Habitat: Bogs and wet soil from middle elevations to the alpine.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
ssp. macroceras – horned butterwort
Pinus albicauliswhite-bark pine
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana and Wyoming.
Habitat: Generally near timberline, preferring south-facing slopes.
Origin: Native
Cones: June-July
Growth Duration: Perennial
Pinus contortalodgepole pine
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and South Dakota.
Habitat: Dry montane forests, rocky balds, coastal bluffs and sand dunes, and sphagnum bogs.
Origin: Native
Cones: April-June
Growth Duration: Perennial
var. contorta – shore pine
var. latifolia – lodgepole pine
Pinus monticolawestern white pine
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Alberta, Montana, and Nevada.
Habitat: Moist valleys and drier slopes, near sea level to mid-elevations in the mountains
Origin: Native
Cones: May-June (cones)
Growth Duration: Perennial
Pinus ponderosaponderosa pine, western yellow pine
Distribution: Occurring mostly east of the Cascades crest in Washington; British Columbia to Baja California, east to the Great Plains.
Habitat: Mostly dry areas in open forests at low to middle elevations.
Origin: Native
Cones: May-June
Growth Duration: Perennial
var. ponderosa – ponderosa pine, western yellow pine
Piptatheropsis exigualittle mountain-ricegrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to Oregon, east to Montana and Colorado.
Habitat: Sandy to rocky soil, mountain meadows to subalpine and alpine ridges and slopes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pisum sativumgarden pea
Distribution: Occurring in scattered locations across Washington; British Columbia to California, east across America in scattered locations.
Habitat: Roadsides, fields, wastelots, and other disturbed areas where escaped from cultivation.
Origin: Introduced
Flowers: May-September
Growth Duration: Annual
Pityopus californicusCalifornia pinefoot
Distribution: Occurring west of the Cascades crest, where known only from Thurston County; Washington to California.
Habitat: Moist, coniferous or mixed-deciduous forests
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Plagiobothrys cognatuscognate popcorn-flower
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains.
Habitat: Wet areas in grasslands, sagebrush, and forest openings.
Origin: Native
Flowers: April-July
Growth Duration: Annual
Plagiobothrys cusickiimatted popcorn-flower
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to California, east to Idaho and Nevada.
Habitat: Wet areas and mudflats in sagebrush, grassland, and forest openings.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Plagiobothrys figuratusfragrant popcorn-flower
Distribution: Occurring chiefly west of the Cascades and in the Columbia River Gorge in Washington; British Columbia to Oregon.
Habitat: Nonalkaline meadows, low ground, and moist fields.
Origin: Native
Flowers: May-July
Growth Duration: Annual
var. figuratus – fragrant popcorn-flower
Plagiobothrys hispidulusharsh popcorn-flower
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to California, east to Wyoming, Utah, and Nevada.
Habitat: Moist to dry open areas at low to middle elevations.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Plagiobothrys leptocladusalkali popcorn-flower, slender-branched popcorn-flower
Distribution: Occurring chiefly east of the Cascades crest in Washington; Washington to Baja California, east to the Rocky Mountains and northern Great Plains.
Habitat: Moist clay flats and beds of drying pools; tolerant of alkali.
Origin: Native
Flowers: April-July
Growth Duration: Annual
Plagiobothrys nothofulvusrusty popcorn-flower
Distribution: Common in the east end of the Columbia River Gorge in Washington; Oregon to northern Baja California, east to Nevada.
Habitat: Open slopes, fields and roadsides.
Origin: Native
Flowers: March-May
Growth Duration: Annual
Plagiobothrys scouleriScouler's popcorn-flower
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Wisconsin and New Mexico.
Habitat: Moist areas, foothills to mid-elevations in the mountains, seldom in alkaline areas.
Origin: Native
Flowers: May-August
Growth Duration: Annual
Plagiobothrys tenellusPacific popcorn-flower, slender popcorn-flower
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to Baja California, east to Idaho and Nevada.
Habitat: Dry, open places at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Plantago arenariasand plantain
Distribution: Occurring west of the Cascades crest in lowland southwestern Washington; British Columbia to California, also in Idaho and central and eastern North America.
Habitat: Sandy areas of roadsides, fields, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: June-October
Growth Duration: Annual
Plantago coronopusbuck-horn plantain
Distribution: Occurring west of the Cascades crest along the coast in Washington; British Columbia to California; also in Manitoba, Texas, and northeastern U.S.
Habitat: Occasional at low elevations along the coast in sandy or disturbed areas.
Origin: Introduced from Eurasia and northern Africa
Flowers: May-October
Growth Duration: Annual, Biennial
Plantago elongataslender plantain
Distribution: Occurring west of the Cascades crest along the coast of western Washington and in the Columbia River Gorge; British Columbia to California, east to Minnesota and Texas.
Habitat: Moist, somewhat saline areas.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Plantago lanceolataEnglish plantain
Distribution: Occuring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast; cosmopolitan.
Habitat: Roadsides, fields, and other disturbed, open areas.
Origin: Introduced from Europe
Flowers: April-August
Growth Duration: Perennial
Plantago macrocarpaAlaska plantain, large-fruited plantain
Distribution: Occurring west of the Cascades crest along the outer coast in Washington; Alaska to Oregon.
Habitat: Coastal wetlands.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Plantago majorcommon plantain, great plantain
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields and other disturbed, open areas.
Origin: Introduced from Europe
Flowers: April-August
Growth Duration: Perennial
Plantago maritima
Distribution: Occurring west of the Cascades crest along the coast in Washington; British Columbia to California.
Habitat: Salt marshes, bluffs and cliffs along the coast.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Plantago patagonicawoolly plantain
Distribution: Occurring chiefly east of the Cascades crest and in the Columbia River Gorge in Washington; British Columbia to California, east across most of North America to the Atlantic Coast; also in South America.
Habitat: Dry, open places at low to middle elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Plantago subnudaMexican plantain, tall coastal plantain
Distribution: Occurring west of the Cascades crest in coastal southwestern Washington; Washington to California.
Habitat: Tidal flats and coastal bluffs.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Platanthera aquiloniseagle rein orchid, Sheviak's bog orchid
Distribution: Occurring east of the Cascades crest in Washington in north-central and northeastern Washington; Alaska to Oregon, east across the northern half of North America to the Atlantic Coast.
Habitat: Wet meadows from the montane to subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Platanthera chorisianachoriso bog orchid
Distribution: Occurring west of the Cascades crest, where known only from Snohomish County in Washington; Aleutian Islands to Vancouver Island, British Columbia, and in Snohomish County, Washington.
Habitat: Moist areas, especially at the edges of streams and bogs.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Platanthera dilatatabog-candle, boreal bog-orchid, white orchid, white rein-orchid, scent-bottle
Distribution: Widely distributed on both sides of the Cascades crest through the mountainous and forested areas of Washington; Alaska to California, east to the Rocky Mountains; also from the Great Lakes region east to the Atlantic Coast.
Habitat: Wet meadows, forest openings, and streambanks from low elevations to the subalpine.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
var. albiflora – white bog-orchid
var. dilatata – white bog-orchid
var. leucostachys – white bog-orchid
Platanthera eleganselegant rein-orchid, hillside rein orchid
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Mostly in dry, open woods and hills where moist in spring.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
ssp. elegans – elegant rein-orchid, hillside rein-orchid
Platanthera elongatadense orchid, dense-flower rein orchid
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Dry, open forest from low to middle elevations.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Platanthera ephemeranthawhite-lip rein-orchid
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California.
Habitat: Moist coniferous forest at low elevations.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Platanthera huronensisnorthern green bog-orchid
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to Oregon, east to the Rocky Mountains; also from north-central to northeastern North America.
Habitat: Moist to boggy areas, often on limestone, low to mid-elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Platanthera obtusatasmall northern bog-orchid, blunt-leaf rein-orchid, one-leaf rein-orchid
Distribution: Occurring east of the Cascades crest in Okanogan County, Washington; Alaska to Oregon, east to Montana, Wyoming and Colorado, east across Canada to the Great Lakes region and northeastern North America; Eurasia.
Habitat: Damp to wet forests at mid-elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
ssp. obtusata – small northern bog-orchid, blunt-leaf rein-orchid, one-leaf rein-orchid
Platanthera orbiculatalarge round-leaf orchid
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Oregon, east across Canada and the northern U.S. to the Atlantic Coast, also in the southeastern U.S.
Habitat: Moist, mossy forests.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Platanthera sparsifloracanyon bog orchid
Distribution: south-central Washington to Baja California, east to Colorado and New Mexico.
Habitat: Wet meadows, fens, and seeps.
Origin: Native
Growth Duration: Perennial
Platanthera strictacanyon bog orchid, needle-spur green orchid, slender bog orchid
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Montana, and Wyoming.
Habitat: Wet meadows, swamps and coniferous forests, low to mid-elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Platanthera transversaroyal rein orchid
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia south to California.
Habitat: Forest understory from low to middle elevations.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Platanthera unalascensisAlaska rein-orchid
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and Nebraska, also from the Great Lakes to the Atlantic Coast.
Habitat: Dry, open woods and gravelly streambanks, low to mid-elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Platanus ×hispanicaLondon plane
Distribution: Occurring east of the Cascades crest along the Columbia River in Washington; scattered locations from central Washington to California, also in eastern North America.
Habitat: River shorelines and adjacent wet meadows.
Origin: Introduced from cultivation
Flowers: April-June
Growth Duration: Perennial
Platanus occidentalisAmerican plane-tree, sycamore
Distribution: Occurring along the shores of the Columbia River in central and south-central Washington; common and native in central and eastern North America.
Habitat: Near streams, lakes, and moist ravines, often where disturbed.
Origin: Introduced
Flowers: April-May
Growth Duration: Perennial
Plectritis brachystemonshortspur white plectritis
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; southern British Columbia to California.
Habitat: Coastal bluffs, lowland prairies, balds at low elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Plectritis ciliosalong-spurred plectritis
Distribution: Occurring east of the Cascades crest in Klickitat County in Washington Klickitat County, Washington, and southwestern Oregon to California.
Habitat: Vernally moist, open slopes and meadows.
Origin: Native
Flowers: April-May
Growth Duration: Annual
Plectritis congestarosy plectritis, sea-blush
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; southwestern British Columbia to California.
Habitat: Open, vernally moist balds, prairies, meadows and slopes, from sea level to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Plectritis macroceralong-horn plectritis, white plectritis
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Vernally moist, open areas; common in shrub-steppe
Origin: Native
Flowers: March-June
Growth Duration: Annual
Pleiacanthus spinosusthorny skeletonweed
Distribution: Occurring east of the Cascades crest in Washington, where known from Yakima County; central Oregon to California, east to the Rocky Mountains.
Habitat: Dry, open, generally rocky places at lower elevations.
Origin: Introduced
Flowers: May-July
Growth Duration: Perennial
Pleuricospora fimbriolatafringed pinesap
Distribution: Occurring chiefly west of the Cascades crest in Washington; Washington to California.
Habitat: Uncommon in coniferous forests at mid-elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pleuropogon refractusnodding semaphore grass
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California.
Habitat: Bogs, stream banks, swampy meadows,and moist, shaded woods, from near sea level toabout 5000 feet elevation in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Poa alpinaalpine bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Oregon, east to the Rocky Mountains, Great Lakes region, and northeastern North America; circumboreal.
Habitat: Alpine areas.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. alpina – alpine bluegrass
Poa annuaannual bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Lawns, fields, parking lots, sidewalks, roadsides, wastelots, prairies and grassy balds, and other disturbed, open areas.
Origin: Introduced from Eurasia
Flowers: March-August
Growth Duration: Annual, Biennial
Poa arcticaArctic bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Oregon, east to Rocky Mountains; circumpolar.
Habitat: Subalpine and alpine areas.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. arctica – arctic bluegrass
Poa bolanderiBolander's bluegrass
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho and Utah.
Habitat: Coniferous forest openings, montane to alpine.
Origin: Native
Flowers: June-August
Growth Duration: Annual
Poa bulbosabulbous bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Disturbed areas from the coast to midmontane.
Origin: Introduced
Flowers: March-June
Growth Duration: Perennial
ssp. vivipara – bulbous bluegrass
Poa compressaflat-stem bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Waste ground, roadsides, open woods and meadows, usually where moist.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial
Poa confiniscoastline bluegrass
Distribution: Occurring west of the Cascades crest in Washington along the coast; British Columbia to California.
Habitat: Coastal sand dunes.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Poa curtifolialittle mountain bluegrass, Wenatchees bluegrass
Distribution: Occurring east of the Cascades crest in central Washington, where endemic to the Wenatchee Mountains.
Habitat: Rocky subalpine and alpine areas, typically on serpentine or ultramafic rock.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Poa cusickiiCusick's bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Saskatchewan and Colorado.
Habitat: Sagebrush plains to alpine meadows and ridges.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
ssp. cusickii – Cusick's bluegrass
ssp. epilis – skyline bluegrass
ssp. pallida – Cusick's bluegrass
ssp. purpurascens – Cusick's bluegrass
Poa fendlerianamuttongrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Great Plains.
Habitat: Rocky to rich slopes in sagebrush, grassland, and open forest, montane to alpine.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
ssp. fendleriana – Vasey's muttongrass
ssp. longiligula – muttongrass
Poa glaucaglaucous bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, and further east to northeastern North America; circumboreal.
Habitat: Alpine areas.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. rupicola – timberline bluegrass
Poa howelliiHowell's bluegrass
Distribution: Occurring west of the Cascades crest and in the Columbia River Gorge in Washington; southern British Columbia to California.
Habitat: Lowland to montane rocky banks, forested slopes, and disturbed areas.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Poa infirmaweak bluegrass
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Annual
Poa interiorinterior bluegrass, woods bluegrass
Distribution: Occurring on both sides of the Cascades crest in northern Washington; Alaska to northern Washington, east to the Rocky Mountains, Great Plains, and Atlantic Coast.
Habitat: Dry to mesic forest and alpine areas, on mossy rocks and scree.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Poa laxifloraloose-flower bluegrass
Distribution: Occurring west of the Cascades crest in Washington; Southern Alaska to northwestern Oregon.
Habitat: Moist woods to rocky, open slopes, from near sea level to lower elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Poa leibergiiLeiberg's bluegrass
Distribution: Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; south-central Washington to northeastern Nevada, east to Idaho.
Habitat: Lowland to montane mossy slopes and moist rocky sites.
Origin: Native
Flowers: March-May
Growth Duration: Perennial
Poa leptocomamarsh bluegrass
Distribution: Occurring in the Cascades Range and Olympic Mountains in Washington; Alaska to California, east to the Rocky Mountains; also in Far Eastern Russia.
Habitat: Margins of lakes, ponds, and streams, subalpine to alpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Poa lettermaniiLetterman's bluegrass
Distribution: Occurring in the Cascades Range in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Mesic to wet, rocky, alpine slopes
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Poa macranthasand-dune bluegrass
Distribution: Occurring west of the Cascades crest along the coast in Washington; southern Alaska to California.
Habitat: Sand dunes along the marine coast.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Poa marcidawithered bluegrass
Distribution: Occurring west of the Cascades crest in Washington; southern Vancouver Island to northwestern Oregon.
Habitat: Openings in rich, mesic, generally old-growth coniferous forest.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Poa ×multnomae
Origin: Native
Poa nemoraliswoodland bluegrass
Distribution: Occurring east of the Cascades crest in Washington; Alaska to Caiifornia; also in eastern North America.
Habitat: Mesic, generally shady habitats at lower elevations.
Origin: Introduced from Europe
Flowers: May-August
Growth Duration: Perennial
Poa nervosaHooker's bluegrass
Distribution: Occurring chiefly east of the Cascades and in the Columbia River Gorge in Washington; British Columbia to Oregon, east to Alberta.
Habitat: Wet rocks and cliffs to mesic forest slopes.
Origin: Native
Flowers: April-August
Growth Duration: Perennial
Poa palustrisfowl bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Sea level to open meadows and forested areas in the mountains, always where moist.
Origin: Introduced from Europe
Flowers: May-August
Growth Duration: Perennial
Poa paucispiculaAlaska bluegrass
Distribution: Occurring in the Cascades Range and Olympic Mountains in Washington; Alaska to Washington, east to the Rocky Mountains.
Habitat: Open, mesic, rocky alpine slopes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Poa pratensisKentucky bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast: circumboreal.
Habitat: Moist, distrurbed areas from the coast to middle elevations.
Origin: Both native and introduced
Flowers: April-October
Growth Duration: Perennial
ssp. angustifolia – Kentucky bluegrass
ssp. irrigata – Kentucky bluegrass
ssp. pratensis – Kentucky bluegrass
Poa secunda
Distribution: Widely distributed throughout Washington; Alaska south to California, east to the Rocky Mountains.
Habitat: Grasslands and forest openings from sea-level to the alpine
Origin: Native
Flowers: April-July
Growth Duration: Perennial
ssp. juncifolia – alkali bluegrass, big bluegrass, Nevada bluegrass
ssp. secunda – curly blue grass
Poa stenanthanarrow-flowered bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Oregon, east to the Rocky Mountains.
Habitat: Meadows and cliffs from middle elevations to the alpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. stenantha – narrow-flower bluegrass
Poa suksdorfiiSuksdorf's bluegrass, western bluegrass
Distribution: Occurring on both sides of the Cascades crest in Washington; south-central British Columbia to central Oregon.
Habitat: Open, rocky ground in alpine areas.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Poa trivialisrough-stalk bluegrass
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Moist deciduous forest, riparian areas, disturbed grassland, and lawns at low to middle elevations.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Perennial
ssp. trivialis – rough-stalk bluegrass
Poa unilateralissea-bluff bluegrass
Distribution: Occurring west of the Cascades crest in Washington; southwestern Washington to California.
Habitat: Coastal bluffs.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
ssp. pachypholis – San Francisco bluegrass
Poa wheeleriWheeler's bluegrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Dry forest, sagebrush desert, and meadows.
Origin: Native
Flowers: April-August
Growth Duration: Perennial
Podagrostis aequivalvisAlaska bent, arctic bent
Distribution: Occurring west of the Cascades crest in Washington; Alaska to the Olympic Peninsula and Mount Rainier.
Habitat: Bogs and wet places near the coast.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Podagrostis humilisalpine bent, mountain bent
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Subalpine or alpine meadows, stream banks, and moist slopes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Podagrostis thurberianaThurber's bent
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Montana and Colorado.
Habitat: Meadows and slopes to lake and stream margins, mostly subalpine or alpine, but down to about 1000 ft elevatin near the coast.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Polemonium californicumlow Jacob's-ladder
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Shaded or moist places from middle elevations to the subalpine.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Polemonium carneumroyal Jacob's-ladder, great polemonium, salmon polemonium
Distribution: Occurring west of the Cascades crest on the Olympic Peninsula and southwestern Washington; Olympic Peninsula to California.
Habitat: Thickets, woodlands and forest openings, from near sea level to moderate elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Polemonium eleganselegant Jacob's-ladder, elegant polemonium
Distribution: Occurring in the Olympics and Cascades mountains in Washington; British Columbia to Washington.
Habitat: Open, often rocky areas, middle to high elevations in the mountains.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Polemonium micranthumannual Jacob's-ladder, annual polemonium
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Common is open plains and foothills, often with sagebrush.
Origin: Native
Flowers: March-May
Growth Duration: Annual
Polemonium occidentalewestern Jacob's-ladder, western polemonium
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and Great Lakes region.
Habitat: Wet meadows and stream banks middle elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Polemonium pectinatumWashington Jacob's-ladder, Washington polemonium
Distribution: Occurring east of the Cascades crest, where endemic to central and eastern Washington.
Habitat: Moist bottom lands in scabland habitat.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Polemonium pulcherrimumshowy polemonium
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: High elevations in the mountains, often in open areas above timberline.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. pulcherrimum – showy Jacob's-ladder
Polemonium viscosumsticky Jacob's-ladder, sticky polemonium
Distribution: Occurring east of the Cascades crest in Washington, where known only from Okanogan County. British Columbia to Oregon and Nevada, east to the Rocky Mountains.
Habitat: Open rocky places at high elevations in the mountains, commonly above timberline.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Polycarpon tetraphyllumfourleaf allseed, fourleaf manyseed
Distribution: Occurring in scattered locations west of the Cascades crest in lowland western Washington; British Columbia to California, also in the southern U.S.
Habitat: Lawns, meadows, roadsides, wastelots, and other disturbed areas at low elevation.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
ssp. tetraphyllum – fourleaf allseed, fourleaf manyseed
Polyctenium fremontiicombleaf
Distribution: Occurring east of the Cascades crest in Washington, where known only from Grant County; disjunct in Washington, otherwise Oregon to California, east to Idaho and Nevada.
Habitat: Open areas in sagebrush-steppe.
Origin: Native
Flowers: April-May
Growth Duration: Perennial
Polygala vulgarismilkwort
Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern British Columbia to southwestern Oregon; in scattered locations elsewhere in the U.S.
Habitat: Disturbed areas at low elevation.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Perennial
Polygonum achoreumBlake's knotweed
Distribution: Reported for Washington, but specimen from Pierce County is likely a misidentification; Alaska to Oregon and Nevada, east across North America to the Atlantic Coast.
Habitat: Disturbed areas.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Polygonum austiniaeAustin's knotweed
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to Alberta and Wyoming.
Habitat: Dry to moist banks and flats, from sagebrush plains to lower mountains, often with ponderosa pine.
Origin: Native
Flowers: June-August
Growth Duration: Annual
Polygonum avicularecommon knotweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Dry or slightly moist, disturbed soil, often where hard-packed.
Origin: Both native and introduced
Flowers: May-October
Growth Duration: Annual
ssp. aviculare – common knotweed, yard knotweed
ssp. buxiforme – American knotweed, prairie knotweed
ssp. depressum – common knotweed, oval-leaf knotweed
ssp. neglectum – narrow-leaf knotweed
Polygonum californicumCalifornia knotweed
Distribution: Occurring in the east end of the Columbia River Gorge in Washington; south-central Washington to California.
Habitat: Dry rocky slopes, gravelly ground at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Polygonum douglasiiDouglas' knotweed, Douglas's knotweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and across the northern U.S. and Canada to the Atlantic Coast.
Habitat: Common in dry to moist areas, lowlands to middle elevations in the mountains.
Origin: Native
Flowers: June-September
Growth Duration: Annual
Polygonum erectumerect knotweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Washington to Oregon and Nevada, east from the Rocky Mountains and northern Great Plains to the Altantic Coast.
Habitat: Dry, disturbed ground.
Origin: Native
Flowers: June-September
Growth Duration: Annual
Polygonum fowleriFowler's knotweed
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California, east across Canada to northeastern North America.
Habitat: Coastal salt marshes.
Origin: Native
Flowers: July-November
Growth Duration: Annual
ssp. fowleri – Fowler's knotweed
Polygonum majusPalouse knotweed, wiry knotweed
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Dry, often semi-barren, gravelly to heavy soil, sagebrush desert to lower mountains.
Origin: Native
Flowers: May-August
Growth Duration: Annual
Polygonum minimumleafy dwarf knotweed, zigzag knotweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Open or semi-barren soil in the alpine and subalpine.
Origin: Native
Flowers: July-September
Growth Duration: Annual
Polygonum nuttalliiNuttall's knotweed
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to Oregon, east to Idaho.
Habitat: Prairies, grassy balds, and forest openings at low to moderate elevations.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Polygonum paronychiabeach knotweed, black knotweed
Distribution: Occurring west of the Cascades crest along the coast; Vancouver Island, B.C., south to Monterey, California.
Habitat: Coastal shorelines and sand dunes.
Origin: Native
Flowers: April-September
Growth Duration: Perennial
Polygonum parryiParry's knotweed, prickly knotweed
Distribution: Occurring in the east end of the Columbia River Gorge in Washington; south-central Washington to California.
Habitat: Vernal pools, seasonally damp ground at low elevations.
Origin: Native
Flowers: June-July
Growth Duration: Annual
Polygonum polygaloideswhite-margined knotweed
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Meadows, vernal pools and rocky ridges, lowlands to mid-elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Annual
ssp. confertiflorum – close-flowered knotweed
ssp. kelloggii – white-margin knotweed
ssp. polygaloides – pokeweed fleeceflower, white-margined knotwee
Polygonum ramosissimumbranched knotweed
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Disturbed areas, often where wet, from low to middle elevations.
Origin: Native
Flowers: July-September
Growth Duration: Annual
ssp. prolificum – proliferous knotweed
ssp. ramosissimum – bushy knotweed
Polygonum sawatchenseSawatch knotweed
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Great Plains.
Habitat: Dry to moist forest openings and meadows from moderate elevations to the subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Annual
ssp. oblivium – sublime knotweed
ssp. sawatchense – Sawatch knotweed
Polygonum spergulariiformefall knotweed, spurry knotweed
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; British Columbia to California, east to Idaho, Montana, and Wyoming.
Habitat: Balds, prairies, and headlands in gravelly, sandy or heavy, dry or moist soil at low elevations.
Origin: Native
Flowers: June-September
Growth Duration: Annual
Polypodium amorphumirregular polypody
Distribution: Occurring chiefly west of the Cascades crest in Washington; southern British Columbia to northern Oregon.
Habitat: Cliff crevices, mostly montane to subalpine.
Origin: Native
Spores: April-August
Growth Duration: Perennial
Polypodium glycyrrhizalicorice fern
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California.
Habitat: Moist banks and rocks, tree trunks and logs, at low elevations
Origin: Native
Growth Duration: Perennial
Polypodium hesperiumwestern polypody
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Moist cliffs, ledges and rock crevices, lowlands to middle elevations in the mountains
Origin: Native
Growth Duration: Perennial
Polypodium scoulerileathery polypody, Scouler's polypody
Distribution: Occurring west of the Cascades crest in Washington; British Columbia south along the coast to California.
Habitat: Cliffs and rocky outcroppings along the coast.
Origin: Native
Growth Duration: Perennial
Polypogon interruptusditch rabbit's-foot grass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, also in Idaho, Texas, and eastern North America.
Habitat: Roadsides, fields, wastelots, and other disturbed areas.
Origin: Introduced from South America
Flowers: June-August
Growth Duration: Perennial
Polypogon maritimusMediterranean rabbit's-foot grass
Distribution: Known from east of the Cascades crest in Klickitat County in Washington; Washington to California, east to Nevada; also in southeastern North America.
Habitat: Shoreline of ponds, lakes and rivers.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Annual
Polypogon monspeliensisannual rabbit's-foot grass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Wet to dry waste areas, including vernal pools where the water is brackish.
Origin: Introduced from Eurasia
Flowers: May-August
Growth Duration: Annual
Polypogon viridisbeardless rabbit's-foot grass
Distribution: Occurring west of the Cascades crest and in the Columbia River Gorge in Washington; British Columbia to California, east to Texas; also in the northeastern U.S.
Habitat: Shores of streams and rivers, dredge spoils.
Origin: Introduced from Eurasia
Flowers: June-September
Growth Duration: Perennial
Polystichum andersoniiVancouver holly-fern, Anderson's sword-fern
Distribution: Occurring chiefly west of the Cascades crest in Washington; southern Alaska to northern Oregon, northern Idaho, and northwest Montana.
Habitat: Deep woods and thickets in the mountains.
Origin: Native
Growth Duration: Perennial
Polystichum brauniiBraun's holly-fern
Distribution: Occurring east of the Cascades crest in Washington, where known only from Pend Oreille County; Alaska to northeastern Washington, east to northern Idaho, also from Great Lakes region to northeastern North America; interruptedly circumboreal.
Habitat: Moist coniferous forest, often where rocky.
Origin: Native
Spores: June-October
Growth Duration: Perennial
Polystichum californicumCalifornia sword-fern
Distribution: Occurring west of the Cascades crest in Washington; southern British Columbia to California.
Habitat: Moist forest understory at low elevations, typically in rock crevices.
Origin: Native
Spores: May-July
Growth Duration: Perennial
Polystichum imbricansimbricate sword-fern, rock sword-fern
Distribution: Occurring on both sides of the Cascades crest in Washington; southwestern British Columbia to California, eastern Idaho, and northern Idaho.
Habitat: Drier habitats such as open rock crevices and dry conifer forest, occasionally on serpentine, mostly at low elevations.
Origin: Native
Growth Duration: Perennial
ssp. imbricans – imbricate fern, narrow-leaved sword fern
Polystichum kruckebergiiholly fern, Kruckeberg's sword fern fern
Distribution: Occurring in the Olympics and Cascades mountains in Washington; southeast Alaska to California, east to Montana, Idaho, Nevada and Utah.
Habitat: Open slopes, typically among rocks; tolerant of serpentine.
Origin: Native
Growth Duration: Perennial
Polystichum kruckebergii × Polystichum munitumhybrid holly fern
Origin: Native
Polystichum lemmoniiLemmon's holly fern, Shasta fern
Distribution: Occurring on both sides of the Cascades crest in the northern half of Washington, southern British Columbia to northern California.
Habitat: Open, rocky slopes near timberline in the mountains, chiefly on serpentine.
Origin: Native
Growth Duration: Perennial
Polystichum lemmonii × Polystichum munitumhidden sword fern
Origin: Native
Polystichum lemmonii × Polystichum scopulinumserpentine holly fern
Origin: Native
Polystichum lonchitismountain fern, northern holly fern
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, also in the Great Lakes region and northeastern North America; Greenland.
Habitat: Talus slopes and cliff crevices, occasionally in coniferous forests, middle to high elevations in the mountains
Origin: Native
Growth Duration: Perennial
Polystichum munitumcommon sword fern, western fern
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to Mexico, east to Montana, and disjunct in South Dakota.
Habitat: Moist coniferous woods, in open to deep shade; from sea-level to midmontane.
Origin: Native
Spores: Spores year-round on fronds
Growth Duration: Perennial
Polystichum munitum × Polystichum scopulinumhybrid sword fern
Origin: Native
Polystichum scopulinummountain holly fern, rock sword fern
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Open slopes, typically associated with rock outcroppings and crevices; tolerant of serpentine.
Origin: Native
Growth Duration: Perennial
Pontederia cordatapickerel-weed
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to Oregon; native to central and eastern and North America.
Habitat: Lakeshores and pond margins, where often escaping from cultivation.
Origin: Introduced from central and eastern North America
Flowers: July-September
Growth Duration: Perennial
Populus albawhite poplar
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Disturbed areas often associated with urban and suburban areas, riparian zones.
Origin: Introduced from Eurasia
Flowers: March-May
Growth Duration: Perennial
Populus ×canescensgray poplar
Origin: Introduced from Europe
Growth Duration: Perennial
Populus deltoideseastern cottonwood
Distribution: Occurring east of the Cascades crest in Washington; introduced from British Columbia to Oregon, east to Idaho; native from east of the Rocky Mountains to the Atlantic Coast.
Habitat: Riparian zones and marshes.
Origin: Introduced from central and eastern North America
Flowers: April-May
Populus nigrablack cottonwood, lombardy poplar
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Old homesteads and fencerows at low elevation.
Origin: Introduced from Europe
Flowers: March-April
Growth Duration: Perennial
Populus tremuloidesquaking aspen
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across much of North America to the Atlantic Coast.
Habitat: Moist areas, low to fairly high elevations in the mountains
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Populus trichocarpablack cottonwood
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta and Wyoming.
Habitat: Streambanks, riparian zones, river corridors, and moist woods, from sea level to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Portulaca oleraceacommon purslane
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: june-September
Growth Duration: Annual
Potamogeton alpinusnorthern pondweed, reddish pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and northern Great Plains; also in eastern North America.
Habitat: Calm water of lakes and slow streams.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton amplifoliusbroad-leaved pondweed, large-leaved pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Atlantic Coast.
Habitat: Lakes and ponds, tolerant of deep waters.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton berchtoldiiBerchtold's pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Often in acidic waters, lakes, slow streams, sloughs, marshes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton crispuscurly pondweed
Distribution: Widely dsitributed on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Slow-moving rivers and streams, lakes, ponds, and backwater channels, generally at low elevations.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
Potamogeton epihydrusribbon-leaved pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains; also in northeastern North America; Europe.
Habitat: Shallow to deep water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton fibrillosusfibrous-stipuled pondweed
Distribution: Occurring west of the Cascades crest in Washington; Washington to California, east to Idaho, Wyoming, and Utah.
Habitat: Warm, shallow water, lakes, springs, streams.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton foliosusleafy pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Standing to moving, shallow water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton friesiiflat-stalked pondweed
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to Washington, east to Alberta, Idaho, Montana, Wyoming, and Utah, northern Great Plains, Great Lakes region, and eastern North America.
Habitat: Lakes, slow streams, and alkaline water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton gramineusgrassy pondweed, variable pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and eastern North America.
Habitat: Standing or running water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton illinoensisillinois pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Northwest Territories to California, east across much of North America to the Atlantic Coast.
Habitat: Ponds and lakes, usually in rather deep, quiet water.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Potamogeton natansfloating pondweed, floating-leaved pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes Region, and eastern North America.
Habitat: In rather shallow, standing water, often where brackish.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton nodosusloddon's pondweed, long-leaved pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Mexico; east over most of the United States to the Atlantic Coast.
Habitat: Shallow to rather deep water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton obtusifoliusblunt-leaved pondweed
Distribution: Occurring west of the Cascades crest in Washington; Alaska to Washington, east across the northern U.S. and Canada to the Atlantic Coast.
Habitat: Lakes, slow streams, and alkaline water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton praelonguswhite-stalked pondweed, whitestem pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes region, and eastern North America.
Habitat: Deep water of lakes.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Potamogeton pusillussmall pondweed
Distribution: British Columbia south on both sides of the Cascades to California, east to the Atlantic.
Habitat: Shallow ponds and streams.
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Potamogeton richardsoniiclasping-leaved pondweed, Richardson's pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Standing or slow-moving water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potamogeton robbinsiifern pondweed, Robbin's pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Montana and Colorado; Minnesota to Maine, south to Virginia in eastern United States.
Habitat: Quiet water, mostly in lakes.
Origin: Native
Flowers: August - September
Growth Duration: Perennial
Potamogeton strictifoliusnarrowleaf pondweed
Distribution: Occurring east of the Cascades crest in Washington, where known only from Okanogan County; Yukon Territory to Washington, east across the northern U.S. and Canada to eastern North America.
Habitat: Alkaline water, lakes and slow streams.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Potamogeton zosteriformiseel-grass pondweed, flat-stem pondweed
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana, and much of north central and northeast United States and adjacent Canada.
Habitat: Lakes, ponds and streams.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla anserinasilverweed cinquefoil, common silverweed
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes region, and northeastern North America.
Habitat: Wet, alkaline areas from coast to arid inlands.
Origin: Native
Flowers: April-October
Growth Duration: Perennial
ssp. anserina – silvery cinquefoil, common silverweed
ssp. pacifica – Pacific silverweed
Potentilla argenteahoary cinquefoil, silver cinquefoil
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to Oregon, east across the northern U.S. and Canada to the Atlantic Coast.
Habitat: Sandy or gravely soil, typically where disturbed.
Origin: Introduced from Eurasia
Flowers: June-July
Growth Duration: Perennial
Potentilla biennisbiennial cinquefoil
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Disturbed areas, typically where moist to wet.
Origin: Native
Flowers: May-August
Growth Duration: Annual, Biennial
Potentilla breweriBrewer's cinquefoil
Distribution: Occurring east of the Cascades crest from central Washington south; central Washington to California, east to Nevada.
Habitat: Moist meadows and stream banks to open slopes at middle to high elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla douglasii
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho, Nevada, and Wyoming.
Habitat: Damp meadows to open forest and rocky slopes at middle elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
var. capitata – horkelia
var. douglasii – Douglas's cinquefoil
Potentilla drummondiiDrummond's cinquefoil
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Idaho, and Montana.
Habitat: Forest openings, meadows and high ridges, middle to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla flabellifoliafan-leaf cinquefoil, fringe-leaf cinquefoil, fan-foil
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California and Nevada, east to Alberta, Montana and Wyoming.
Habitat: Common in moist meadows from middle to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla glaucophyllablueleaf cinquefoil, different-leaved cinquefoil, diverse-leaved cinquefoil, vari-leaved cinquefoil
Distribution: Occurring on both sides of the Cascades crest and in the Olympic Mountains in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Moist subalpine and alpine meadows, and along stream banks in high mountain forests.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla gordoniiGordon's ivesia, alpine mousetail
Distribution: Occurring chiefly east of the Cascades crest from central Washington south; central Washington to California, east to Montana, Wyoming, and Colorado.
Habitat: Rocky slopes, grassland, sagebrush, forest openings, and subalpine to alpines ridges.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla gracilisslender cinquefoil
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and eastern Canada.
Habitat: Varied habitats; moderately saline soil, grasslands, moist areas in shrub-steppe, forested mountains and subalpine meadows.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. brunnescens – glandular cinquefoil
var. flabelliformis – comb-leaf cinquefoil, Elmer's cinquefoil, Idaho cinquefoil
var. gracilis – Hall's cinquefoil, slender cinquefoil, wooly cinquefoil
var. pulcherrima – beautiful cinquefoil
Potentilla hookerianaHooker's cinquefoil
Distribution: British Columbia to Nevada, east to Alberta, Montana, Wyoming, and Colorado.
Habitat: Alpine limy cliffs, rocky slopes, fellfields, scree, and river canyons.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla hyparcticasubarctic cinquefoil
Distribution: Known only from west of the Cascades crest in Whatcom County in Washington; Alaska to Washington, also south to south-central Montana and Wyoming; circumboreal.
Habitat: Alpine rocky slopes, talus, heath, turf, and snowmelt meadows, often acidic.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. elatior – subarctic cinquefoil
Potentilla jepsoniiJepson's cinquefoil
Origin: Native
var. kluanensis – Kluane cinquefoil
Potentilla newberryiNewberry's cinquefoil
Distribution: Known historically (1898) from the Columbia River Gorge in Washington, now likely extirpated; central Oregon to California, east to northwestern Nevada.
Habitat: Vernal pools, shores, and mudflats.
Origin: Native
Flowers: April-May
Growth Duration: Annual, Biennial, Perennial
Potentilla niveasnow cinquefoil
Distribution: Occurring on both sides of the Cascades crest in northern Washington; Alaska to Washington, east to the southern Rocky Mountains to Colorado, further east to eastern North America.
Habitat: Arctic tundra and gravel bars to alpine slopes and meadows.
Origin: Native
Flowers: June August
Growth Duration: Perennial
Potentilla norvegicaNorwegian cinquefoil, rough cinquefoil
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Usually in moist soil, often along irrigation ditches or in waste places.
Origin: Native
Flowers: May-August
Growth Duration: Annual, Biennial, Perennial
Potentilla pensylvanicaPennsylvania cinquefoil
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east to the Great Plains, and further east across the northern U.S. and Canada to the Atlantic Coast; also in Eurasia.
Habitat: Damp alpine meadows, rocky slopes, ridges, and talus.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. ovium – Jepson's cinquefoil
Potentilla rectasulphur cinquefoil
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, but not in Yukon Territory, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields, trails, and disturbed ground.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial
Potentilla rivalisbrook cinquefoil, river cinquefoil
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to central North America, and further east to the northeastern U.S.
Habitat: Damp soil, especially along rivers and around lakes, ponds, and swamps at low elevations.
Origin: Native
Flowers: May-September
Growth Duration: Annual, Biennial
Potentilla supinabushy cinquefoil
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, Great Plains, and east across Canada and the midwestern U.S. to northeastern North America.
Habitat: Sandy stream banks, lake shores, and moist flats.
Origin: Native
Flowers: June-July
Growth Duration: Annual, Biennial
ssp. paradoxa – bushy cinquefoil
Potentilla tweedyiTweedy's mousetail
Distribution: Occurring east of the Cascades crest in Washington; Washington to Idaho and Montana.
Habitat: Dry, open to wooded areas, middle to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Potentilla villosanorthern cinquefoil, villous cinquefoil
Distribution: Occurring in the North Cascades, Olympic Mountains, and at Mt. Rainier in Washington; Alaska to Oregon.
Habitat: Arctic tundra to alpine ridges, talus slopes and rock crevices.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Poteridium annuumannual burnet, prairie burnet
Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to northern California, east to the Rocky Mountains, also in eastern North America.
Origin: Native
Growth Duration: Annual
Poterium sanguisorbafodder burnet, small burnet
Distribution: Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington; southern British Columbia to California, east to the Great Plains, also in eastern North America.
Habitat: Roadsides, shores, pastures, wastelots, and other disturbed open areas.
Origin: Introduced from Eurasia and North Africa
Flowers: June-August
Growth Duration: Perennial
var. polygamum – burnet bloodwort, fodder burnet, small burnet
Primula austrofrigidumfrigid shooting star, Tillamook
Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern Washington to northwestern Oregon.
Habitat: Moist basaltic slopes, cliff faces, in coniferous forests along streams, or in alpine meadows.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Primula conjugensdesert shooting star, slimpod shooting star
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to Alberta and Wyoming.
Habitat: Vernally moist areas in sagebrush to meadows at mid-elevations in the mountains
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Primula hendersoniibroad-leaved shooting star, Henderson's shooting star
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California.
Habitat: Woods and prairies, at low elevations in our area.
Origin: Native
Flowers: March-June
Growth Duration: Perennial
Primula jeffreyiJeffrey's shooting star, tall mountain shooting star
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Montana and Wyoming.
Habitat: Wet meadows and stream banks, mid- to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Primula latilobawhite shooting star
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to northern Oregon; also in central Idaho
Habitat: Streambanks and other wet places at moderate elevations in the mountains
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Primula pauciflorapretty shooting star
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Mexico, east to the Great Plains.
Habitat: Coastal prairies to inland saline swamps and shrub-steppe, sea level to timberline
Origin: Native
Flowers: April-July
Growth Duration: Perennial
var. cusickii – Cusick's shooting star, sticky shooting star
var. macrocarpa – Alaskan shooting star
var. pauciflora – dark-throated shooting star
Primula poeticanarcissus shooting star, poet's shooting star
Distribution: Occurring east of the Cascades crest in Washington; central Washington to northern and northeastern Oregon.
Habitat: Grassy slopes to drier woods, usually where vernally moist, often near seeps or springs along basaltic outcrops.
Origin: Native
Flowers: March-May
Growth Duration: Perennial
Primula tetrandraalpine shooting star
Distribution: Occurring in and east of the Cascades in south-central Washington; Washington to California, east to Utah and Arizona.
Habitat: Moist to wet areas in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Prosartes hookerifairy-bells, Hooker's fairy-bells
Distribution: Occurring in forested areas on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana.
Habitat: Moist, shady, wooded areas, sea level to mid-elevations in the mountains.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Prosartes smithiiSmith's fairy-bells
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California.
Habitat: Open to dense moist woods at lower elevations.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Prosartes trachycarpawartberry fairy-bells
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to Oregon, east to the Rocky Mountains and Great Plains of the U.S. and Canada, reaching Ontario and Michigan.
Habitat: Wooded slopes, often near streams, and in aspen groves.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Prunella vulgarisself-heal
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Moist areas, sea level to moderate elevations in the mountains.
Origin: Both native and introduced
Flowers: May-September
Growth Duration: Perennial
var. lanceolata – heal-all, self-heal
var. vulgaris – heal-all, self-heal
Prunus americanaAmerican plum, wild plum
Distribution: Occurring east of the Cascades crest in southcentral and southeastern Washington; Washington to Oregon, east to the Rocky Mountains, and further east across North America to the Atlantic Coast.
Habitat: Along watercourses, and on open or wooded, moist or dry areas from the plains into the lower mountains.
Origin: Native and introduced from further east of Washington
Flowers: April-May
Growth Duration: Perennial
Prunus armeniacaapricot
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains, and in scattered areas eastward to the Atlantic Coast.
Habitat: Sagebrush desert, ledges, gravel or clay slopes, thickets, and shorelines
Origin: Introduced from China
Flowers: March-May
Growth Duration: Perennial
Prunus aviumsweet cherry
Distribution: Occurring chiefly west of the Cascades crest in Washington, though distributed widely throughout the state; British Columbia to California, east to the Rocky Mountains, also in eastern North America.
Habitat: Forest edges, fields, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: April-May
Growth Duration: Perennial
Prunus cerasiferacherry plum, Flowering plum
Distribution: Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington, but also in southeastern Washington; British Columbia to California, east to Idaho; also in northeastern North America.
Habitat: Open, disturbed areas typically at low elevations.
Origin: Introduced
Flowers: March-April
Growth Duration: Perennial
Prunus cerasussour cherry
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east to Idaho and Montana, also east from the Great Plains to the midwestern U.S. and northeastern North America.
Habitat: Roadsides, thickets, forest edge, and fields.
Origin: Introduced from Eurasia
Flowers: March-May
Growth Duration: Perennial
Prunus domesticacultivated plum
Distribution: Occurring chiefly west of the Cascades crest in Washington; Washington to California, east to Idaho and Utah; in scattered locations of central and northeastern U.S.
Habitat: Fields, roadsides, forest openings, abandoned homesteads, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: March-May
Growth Duration: Perennial
Prunus dulcisalmond
Distribution: Occurring in scattered locations east of the Cascades crest and in the Columbia River Gorge in Washington; Washington, Idaho, and California.
Habitat: Disturbed areas, mostly along riparian zones and rocky slopes.
Origin: Introduced from western Asia and northern Africa
Flowers: March-May
Growth Duration: Perennial
Prunus emarginatabitter cherry
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Thickets, rocky slopes, open forests, shorelines, and openings, from the lowlands to subalpine.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Prunus laurocerasuslaurel cherry, cherry-laurel, English laurel
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California.
Habitat: Fields, forest edge, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Perennial
Prunus lusitanicaPortugal laurel
Distribution: Occurring west of the Cascades crest in lowland western Washington; British Columbia to California.
Habitat: Thickets, forested slopes, grasslands, and shorelines.
Origin: Introduced from Europe
Flowers: April-June
Prunus mahalebmahaleb cherry, perfumed cherry
Distribution: Ocurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana, Idaho, Utah, and also in the eastern United States.
Origin: Introduced from Eurasia
Flowers: May - June
Growth Duration: Perennial
Prunus padusEuropean bird cherry
Distribution: Occurring west of the Cascades crest in Washington; southern Alaska, southwestern British Columbia to northwestern Washington, Montana, and eastern North America.
Habitat: Ornamental, occasionally escapes
Origin: Introduced from Eurasia and northern Africa
Flowers: April-June
Growth Duration: Perennial
Prunus persicapeach
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; southwestern British Columbia to California, east to Idaho; also in eastern North America.
Habitat: Thickets, shores, and disturbed ground.
Origin: Introduced from eastern Asia
Flowers: April-June
Growth Duration: Perennial
Prunus ×pugetensisPuget Sound cherry
Distribution: Occurring chiefly west of the Cascades crest in Washington; Southwestern British Columbia to northwestern Oregon, east in the Columbia River Gorge and in Chelan County, WA.
Habitat: Low elevations in forests or forest edges, or disturbed areas, typically where both parent species are present.
Origin: Native
Flowers: April-May
Growth Duration: Perennial
Prunus spinosablackthorn
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; southwestern British Columbia to southern Oregon, east to Idaho.
Habitat: Moist draws, thickets, hillsides, roadsides, and railroads.
Origin: Introduced from Eurasia and northern Africa
Flowers: April-May
Growth Duration: Perennial
Prunus tomentosaNanking cherry
Distribution: Occurring east of the Cascades crest in central Washington; also in Utah, and from northern Great Plains east to northeastern North America.
Habitat: Thickets and hedgerows.
Origin: Introduced from Asia
Flowers: April-May
Growth Duration: Perennial
Prunus virginianacommon chokecherry, western chokecherry, white chokecherry
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Thickets, open forest, shorelines, rocky slopes, and roadsides.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Prunus yedoensisYoshino cherry
Distribution: Occurring west of the Cascades crest in lowland western Washington; also occurring in central California.
Habitat: Thickets and shorelines, often where disturbed.
Origin: Introduced from Japan
Flowers: March-April
Growth Duration: Perennial
Psathyrostachys junceaRussian wild-rye
Distribution: Occurring east of the Cascades crest in Washington, where likely more common than specimens or photo evidence suggests; Alaska to Washington, also in the Rocky Mountains and Great Plains.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
×Pseudelymus saxicola
Origin: Native
Pseudognaphalium californicumCalifornia cudweed, California everlasting
Distribution: Occurring west of the Cascades crest in Washington; southwestern Washington to Baja California, Mexico.
Habitat: Sandy soils, dunes, coastal canyons and chaparral.
Origin: Native
Flowers: June-July
Growth Duration: Annual, Biennial
Pseudognaphalium luteoalbumweedy cudweed, red-tip rabbit-tobacco, jersey rabbit tobacco
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Washington to California, east across the southern U.S. to Florida, also in New York.
Habitat: Roadsides, fields, wastelots, and other disturbed areas at low elevations.
Origin: Introduced from Eurasia
Flowers: June-October
Growth Duration: Annual
Pseudognaphalium macouniisticky cudweed, winded cudweed, Macoun's rabbit-tobacco, Macoun's rabbit tobacco
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Dry, open areas from low to middle elevations.
Origin: Native
Flowers: June-August
Growth Duration: Annual, Biennial
Pseudognaphalium stramineumcotton batting cudweed
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California, east to the Great Plains of the U.S.; also in scattered states along the Atlantic Coast.
Habitat: Open, usually moist places, often in disturbed soil.
Origin: Native
Flowers: June-October
Growth Duration: Annual, Biennial
Pseudognaphalium thermaleslender cudweed, northwestern rabbit-tobacco
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana and Utah.
Habitat: Dry, sandy banks and ditches, open woods of ponderosa pine and Douglas fir, and mixed deciduous forests.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Pseudoroegneria spicatabluebunch wheatgrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Sagebrush desert and ponderosa pine forest openings, occasionally to the subalpine.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pseudosasa japonicaJapanese bamboo
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California.
Habitat: Forest edge, roadsides, and other disturbed areas at low elevations where escaping from cultivation.
Origin: Introduced from Asia
Growth Duration: Perennial
Pseudostellaria jamesianasticky chickweed, sticky starwort
Distribution: Occurring chiefly east of the Cascades crest in Washington; Chelan County, Washington to California, east to Idaho, Montana, Wyoming, Utah, and New Mexico.
Habitat: Moist or dry open woods, rocky slopes and meadows, from moderate to high elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Pseudotsuga menziesiiDouglas-fir
Distribution: Widely distributed in forested areas on both sides of the Cascades crest in Washington; British Columbia to California, east to Alberta and Colorado.
Habitat: Moist to dry areas from sea level to mid-elevations in the mountains, occasionally to timberline.
Origin: Native
Cones: April-May
Growth Duration: Perennial
var. glauca – pino real Colorado, Rocky Mountain Douglas-fir
var. menziesii – coast Douglas-fir
Psilocarphus brevissimusdwarf woolly-marbles
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the northern Great Plains and Rocky Mountains.
Habitat: Dried beds of vernal pools.
Origin: Native
Flowers: May-July
Growth Duration: Annual
var. brevissimus – dwarf woollyheads
Psilocarphus elatiortall woollyheads
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho and Montana.
Habitat: Dried beds of vernal pools and other open, moist places.
Origin: Native
Flowers: May-August
Growth Duration: Annual
Psilocarphus oregonusOregon woollyheads
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho and Nevada.
Habitat: Dried beds of vernal pools, and seasonally wet rocky slopes.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Psilocarphus tenellusslender woollyheads
Distribution: Occurring on both sides of the Cascades crest in Washington; southwestern British Columbia to California, east to Idaho.
Habitat: Dry or seasonally moist barren or wooded slopes or flats, often on disturbed sites.
Origin: Native
Flowers: March-August
Growth Duration: Annual
Pteridium aquilinumbracken, bracken fern
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast; circumboreal.
Habitat: Common in moist to dry woods, open slopes and disturbed sites
Origin: Native
Spores: Spores April-October
Growth Duration: Perennial
ssp. pubescens – northern bracken, bracken fern
Pterospora andromedeawoodland pinedrops
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Great Plains and northeastern North America
Habitat: Common in coniferous forests, especially where ponderosa is dominant.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Puccinellia distansEuropean alkaligrass, weeping alkaligrass
Distribution: Occurring chiefly east of the Cascades in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Moist soil, especially where alkaline.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
Puccinellia maritimacoast alkaligrass
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to Washington; also in northeastern North America.
Habitat: Coastal, salt and brackish marshes, tidelands.
Origin: Introduced from Europe
Flowers: May-August
Growth Duration: Perennial
Puccinellia nutkaensisNootka alkaligrass, shining alkaligrass
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California; also in northeastern North America.
Habitat: Coastal marine shores, salt marshes, sea ledges, small rocky islands, gravel beaches.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Puccinellia nuttallianaNuttall's alkali grass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Minnesota, Kansas, eastern and eastern North America.
Habitat: Coastal salt marshes and inland alkali shores and stream banks.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Puccinellia pumilasmall alkaligrass
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California; also in the Russian Far East.
Habitat: Coastal mudflats, salt marshes, estuaries, sandy or rocky marine shores.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pueraria montanakudzu
Distribution: Not currently known to occur in Washington; also reported for Oregon, otherwise widespread in eastern North America, especially southeastern U.S.
Habitat: Disturbed, open areas and forest edge.
Origin: Introduced
Flowers: May-June
Purshia tridentataantelope-brush, bitterbrush
Distribution: Widely distributed east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and Nebraska.
Habitat: Sagebrush desert and shrub-steppe to ponderosa pine forests.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
var. tridentata – anteleope-brush, bitterbrush
Pyracantha coccineafirethorn, scarlet firethorn
Distribution: O Occurring in scattered locations across Washington; British Columbia south to California, east to the Atlantic Coast along the southern half of the U.S.
Habitat: Disturbed areas, wastelots, and forest margins often near towns and cities where escaped from cultivation.
Origin: Introduced from western Asia
Flowers: May-June
Growth Duration: Perennial
Pyracantha fortuneanaChinese firethorn
Distribution: Occurring west of the Cascades crest in lowland western Washington; southern British Columbia to California and Arizona, also in the southern and southeastern U.S.
Habitat: Disturbed, open areas where escaped from cultivation through bird-dispersal.
Origin: Introduced from China
Flowers: January-May
Growth Duration: Perennial
Pyrola aphyllaleafless wintergreen
Distribution: Occurring on both sides of the Cascades crest in Washington; southwestern British Columbia to Baja California, east to Idaho.
Habitat: Dry coniferous forests at low to moderate elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Pyrola asarifoliacommon pink wintergreen, liver-leaf wintergreen
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Moist ground in woodlands and forests, from low to middle elevations.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
ssp. asarifolia – pink pyrola, common pink wintergreen, liver-leaf wintergreen
ssp. bracteata – pink pyrola
Pyrola chloranthagreen-flower wintergreen
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains and across northern U.S. and Canada to the Atlantic Coast.
Habitat: Chiefly in coniferous forests at moderate to mid-elevations, usually where moist.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pyrola dentatatoothleaf pyrola
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana and Wyoming.
Habitat: Montane coniferous forest understory.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pyrola ellipticawhite wintergreen
Distribution: Occurring on both sides of the Cascades crest in Washington to the Mount St. Helens area; British Columbia to Washington east to Montana and Wyoming, northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Dry montane forests.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Pyrola minorlesser wintergreen, snowline wintergreen
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains; east across Canada and northern U.S. to the Atlantic Coast.
Habitat: Uncommon, mostly in moist areas in coniferous woods, moderate to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pyrola pictawhite-vein wintergreen
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Coniferous woods, especially ponderosa pine, moderate to mid-elevations in the mountains
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Pyrrocoma carthamoideslarge-flowered goldenweed
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to Idaho, Montana, Wyoming, and Nevada.
Habitat: Open hillsides, meadows and forest openings from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
var. carthamoides – Columbia goldenweed, rayless goldenweed
var. cusickii – narrowhead goldenweed
Pyrrocoma hirtahairy goldenweed, sticky goldenweed
Distribution: Occurring east of the Cascades crest in central Washington; central Washington, the mountains of northeast Oregon and adjacent Idaho, south to northeast California.
Habitat: Meadows and open or sparsely wooded slopes in the foothills to middle elevations in the mountains.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
var. sonchifolia – large sticky goldenweed
Pyrrocoma liatriformisPalouse goldenweed
Distribution: Occurring east of the Cascades crest in eastern Washington; eastern Washington and adjacent Idaho.
Habitat: Grassy hillsides and prairies.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Pyrrocoma scaberulapalouse goldenweed
Distribution: Occurring in the southeastern corner of Washington; southeastern Washington to adjacent Oregon and Idaho.
Habitat: Grasslands and open hillsides at low to middle elevations.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Pyrus communiscommon pear
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho, Montana, Utah and New Mexico; also from southcentral U.S. east and northeast to the Atlantic Coast.
Habitat: Grasslands, thickets, shorelines, and forest openings;
Origin: Introduced from Eurasia
Flowers: April-June
Growth Duration: Perennial