Poaceae
Grass Family
Synonyms:
Gramineae [HC]
102 genera
328 species
106 subspecies and varieties
Show only taxa with photos
Order by:
Scientific name
Common name
Display as:
Achnatherum hendersoniiHenderson's needlegrass
Distribution: Occurring east of the Cascades crest in Douglas, Kittitas, and Yakima counties; central Washington to Jefferson County, Oregon.
Habitat: Dry, rocky, shallow soil, in sagebrush desert or ponderosa pine forest openings.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Achnatherum hymenoidesIndian ricegrass
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Great Plains.
Habitat: Grasslands, desert plains, and foothills, especially on rocky or sandy soil.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Achnatherum lemmoniiLemmon's needlegrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains.
Habitat: Grassy balds, prairies, sagebrush grasslands, and ponderosa pine forest, from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Achnatherum nelsoniiNelson's needlegrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; Yukon Territory to California, east to the northern Great Plains and Colorado.
Habitat: Moist to mesic, montane to subalpine meadows and open forest.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. dorei – Nelson's needlegrass
ssp. nelsonii – Nelson's needlegrass
Achnatherum occidentalecommon western needlegrass
Origin: Native
Growth Duration: Perennial
ssp. californicum – California needlegrass
ssp. pubescens – western needlegrass
Achnatherum richardsoniiRichardson's rice grass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Achnatherum thurberianumThurber's rice grass
Origin: Native
Flowers: Late May - June
Growth Duration: Perennial
Aegilops cylindricajointed goat grass
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east across most of the United States to the Atlantic Coast.
Habitat: Waste ground and roadsides; a troublesome weed in wheat.
Origin: Introduced from southern Europe
Flowers: May-July
Growth Duration: Annual
×Agropogon lutosusperennial beardgrass
Origin: Introduced
Agropyron cristatumcrested wheatgrass
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east across much of North America to the Atlantic Coast.
Habitat: Dry, open areas where distiurbed; frequently planted for soil stabilization and forage.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
Agropyron fragileSiberian wheatgrass
Origin: Introduced
Agrostis capillariscolonial bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Open, disturbed areas often at low elevations.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial
Agrostis castellanaHighland bentgrass, dryland browntop
Distribution: Occurring west of the Cascades crest in lowland western Washington: southwestern British Columbia to Oregon.
Habitat: Disturbed sites, roadsides, and gravel bars.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Perennial
Agrostis densifloraCalifornia bentgrass
Distribution: Occurring west of the Cascades crest in western Washington along the outer coast; coastal Washington to California.
Habitat: Coastal bluffs.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Agrostis exarataspiked bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Nebraska and Texas.
Habitat: Moist areas, from near sea level to mid-elevations in the mountains.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Agrostis giganteablack bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Disturbed sites, roadsides, edge of agricultural fields, mostly at low elevations.
Origin: Introduced from Eurasia
Flowers: June-September
Growth Duration: Perennial
Agrostis idahoensisIdaho bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Subalpine and alpine meadows, along wet seepage areas, bogs, and wet openings in coniferous forests.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Agrostis mertensiiMerten's bentgrass, northern bentgrass
Distribution: Occurring in the Cascades Range in Washington; Alaska to northern Washington; circumboreal.
Habitat: Rocky alpine meadows and ridgelines.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Agrostis microphyllasmall-leaf bentgrass
Distribution: Occurring west of the Cascades crest and in the Columbia River Gorge in Washington; southwestern British Columbia to California.
Habitat: Seasonally wet areas on thin, rocky or sandy substrates, vernal pools, cliffs, and serpentine areas.
Origin: Native
Flowers: May-June
Growth Duration: Annual
Agrostis ×murbeckii
Origin: Introduced
Agrostis oregonensisOregon bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Montana, Wyoming, and Nevada.
Habitat: Stream and lake margins, damp woodlands and meadows.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Agrostis pallensseashore bentgrass
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east to western Montana and Utah.
Habitat: Coastal sands and cliffs, meadows, open, dry lowlands to subalpine forest.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Agrostis scabrarough bentgrass
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Disturbed sites in grassl, open forest, marshes, and lakesides, often along roads and ditches.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Agrostis stoloniferaspreading bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Wet, disturbed areas that include streambanks, flooded fields, and ditches at low to moderate elevations.
Origin: Introduced from Eurasia
Flowers: June-September
Growth Duration: Perennial
Agrostis variabilisalpine bentgrass
Distribution: Occurring on both sides of the Cascades crest in Washington British Columbia to California, east to the Rocky Mountains.
Habitat: Wet subalpine and alpine seeps and meadows.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Aira caryophylleasilver hairgrass
Distribution: Occurring west of the Cascades crest in Washington and east in the Columbia River Gorge; British Columbia to California, east to Idaho and Wyoming, also in the southeastern U.S. and northeastern North America.
Habitat: Balds, prairies, meadows, forest openings, roadsides, wastelots, and other open areas at low to middle elevations.
Origin: Introduced Eurasia and North Africa
Flowers: May-August
Growth Duration: Annual
var. caryophyllea – silver hairgrass
Aira elegansdelicate hairgrass
Origin: Introduced
Aira praecoxearly silver-hair grass
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia south to California; Nova Scotia south to Virginia in eastern North America.
Habitat: Gravelly prairies, sea bluffs and dunes near the coast, also in other disturbed, open areas at low elevations.
Origin: Introduced
Flowers: April-September
Growth Duration: Annual
Alopecurus aequalislittle foxtail, short-awn foxtail
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Shores, riverbanks, vernal pools, sloughs, wet meadows, and seeps, often submersed.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Alopecurus arundinaceuscreeping meadow-foxtail
Distribution: Occurring east of the Cascades crest in Washington; central British Columbia to Washington, east to the Rocky Mountains and northern Great Plains; also in scattered locations in eastern North America.
Habitat: Alkaline meadows and shores, ditches, shores.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Perennial
Alopecurus carolinianustufted meadow-foxtail
Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to California, east to the Atlantic Coast.
Habitat: Shores, wet meadows, vernal pools, ditches.
Origin: Introduced from central North America?
Flowers: May-July
Growth Duration: Annual
Alopecurus geniculatuswater fescue
Distribution: Distributed on both sides of the Cascades in Washington; Alaska south to California, east to the Atlantic Coast in Canada.
Habitat: Wet places, often in standing water.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Alopecurus myosuroidesslender meadow-foxtail
Distribution: Introduced in many parts of North America; occasional in Washington and Oregon.
Habitat: Wet places.
Origin: Introduced
Flowers: June - August
Growth Duration: Annual
Alopecurus pratensisfield meadow-foxtail
Distribution: Alaska to Newfoundland, south to Oregon, Idaho, Montana, Missouri, and New Jersey. Found on both sides of the Cascades in WA.
Habitat: Swampy areas in meadows, in irrigated fields, and along roadsides.
Origin: Introduced from Europe
Flowers: June - July
Growth Duration: Perennial
Alopecurus saccatusPacific meadow-foxtail
Distribution: Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; Washington and southwestern Oregon to California.
Habitat: Lowland vernal pools, shores, wet scabland, meadows.
Origin: Native
Flowers: May-June
Growth Duration: Annual
Ammophila arenariaEuropean beachgrass
Distribution: Introduced along the Pacific coast from southeast Washington the California.
Habitat: Sandy beaches and dunes.
Origin: Introduced
Flowers: June-August
ssp. arenaria – European beach grass
Ammophila breviligulataAmerican beachgrass
Origin: Introduced
ssp. breviligulata – American beachgrass
Anthoxanthum aristatumannual vernalgrass
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; British Columbia south to California; eastern half of North America.
Habitat: Meadows, grasslands, forest openings, and other disturbed, open areas at low to moderate elevations.
Origin: Introduced
Flowers: May-July
Growth Duration: Annual
ssp. aristatum – small sweet vernal grass
Anthoxanthum odoratumsweet vernalgrass
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, southern Great Plains, and eastern North America.
Habitat: Roadsides, fields, meadows, prairies, balds, lawns, and other disturbed open areas at low elevations.
Origin: Introduced from Europe
Flowers: April-July
Growth Duration: Perennial
Apera interruptadense silky-bent
Distribution: Occurring chiefly east of the Cascades in Washington; British Columbia to California, east to the Rocky Mountains; also in the central U.S., Great Lakes region, and northeastern U.S.
Habitat: Dry wasteland and other disturbed areas in shrub-steppe and open coniferous forests.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Annual
Aristida purpureathreeawn
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to central Canada and the central U.S.
Habitat: Desert plains and grasslands, into the foothills.
Origin: Native
Flowers: June - July
Growth Duration: Annual, Perennial
var. longiseta – red threeawn
Arrhenatherum elatiustall oatgrass
Distribution: Introduced more commonly west of the Cascades, British Columbia south to California, east to Idaho and Montana.
Habitat: Meadows and pastures.
Origin: Introduced
Flowers: May - July
Growth Duration: Perennial
ssp. bulbosum – bulbous oatgrass
ssp. elatius – bulbous oatgrass
Avena barbatabarbed oat
Distribution: Introduced and common in southwest United States; occasional in Washington and western Oregon.
Habitat: Roadsides and waste land.
Origin: Introduced
Flowers: May - June
Growth Duration: Annual
Avena fatuawild oat
Distribution: Common introduction in most of western North America.
Habitat: A weed in grain fields, roadsides and waste ground.
Origin: Introduced
Flowers: May - September
Growth Duration: Annual
Avena sativaoat
Distribution: Commonly cultivated throught the United States and Canada, occasionally escaping but usually not persisting.
Habitat: Roadsides and field margins.
Origin: Introduced
Flowers: June - August
Growth Duration: Annual
Beckmannia syzigachneAmerican slough grass
Distribution: Alaska to California, east from the coast to Manitoba and the Great Lakes region
Habitat: Pond margins, marshes and ditches at low elevations
Origin: Native
Flowers: June - July
Growth Duration: Annual
Brachypodium sylvaticumfalse brome
Distribution: Occurring west of the Cascades crest in lowland western Washington; British Columbia to California; also in Virginia.
Habitat: Roadsides and other disturbed, open areas at low elevations.
Origin: Introduced
Flowers: April-June
Growth Duration: Annual
ssp. sylvaticum – false brome
Briza maximabig quakinggrass
Origin: Introduced
Flowers: May - June
Growth Duration: Annual
Briza minorlittle quaking grass
Distribution: Well established in Eastern North America; occasional on the West coast.
Habitat: Dry waste areas.
Origin: Introduced from the Mediterranean region
Flowers: May - June
Growth Duration: Annual
Bromus arenariusAustralian brome
Origin: Introduced
Bromus briziformisrattlesnake brome
Distribution: Southern British Columbia south to California, east to Idaho and Montana; occasional in eastern United States.
Habitat: Waste ground, roadsides, and overgrazed areas.
Origin: Introduced
Flowers: Late May - July
Growth Duration: Annual
Bromus ciliatusfringed brome
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Bromus commutatusmeadow brome
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Waste ground, meadows, roadsides.
Origin: Introduced
Flowers: June-August
Growth Duration: Annual
Bromus diandrusgreat brome, ripgut brome, ripgut grass
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, southern Great Plains, and in eastern North America.
Habitat: Grassy balds, prairies, roadsides, wastelots, and other disturbed open areas at low to moderate elevations.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Bromus hordeaceussoft chess
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Baja California, east to Idaho and Montana.
Habitat: Prairies, bluffs, grasslands, waste ground, roadsides, dry hillsides, and other disturbed areas.
Origin: Introduced
Flowers: April-July
Growth Duration: Annual
Bromus inermissmooth brome
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast
Habitat: Roadsides, fields, ditches, meadows, parks, and other disturbed open areas; often planted for hay and soil stabilization.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
Bromus japonicusJapanese brome
Distribution: East of the Cascades, southern British Columbia to California, east across Canada and most of eastern United States.
Habitat: Sagebrush desert and grasslands to lower mountain forests; often a weed of roadsides and waste land.
Origin: Introduced
Flowers: June - August
Growth Duration: Annual
Bromus orcuttianuschinook brome
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern Washington to California, east to Nevada and Arizona.
Habitat: Dry hillsides, rocky slopes, montane meadows, and open coniferous forests.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Bromus pacificusPacific brome
Distribution: West of the Cascades crest in Washington; Alaska south to Oregon.
Habitat: Meadows and forest openingsat low elevations, often near or along the coast.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Bromus pumpellianuspumpelly brome
Distribution: Occurring east of the Cascades crest in Washington; Alaska to Oregon, east to Rocky Mountains.
Habitat: Stream banks, lake shores, sand dunes, meadows, grassy slopes, and roadsides
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. pumpellianus – arctic brome
Bromus racemosusbald brome
Origin: Introduced
Growth Duration: Annual
Bromus rubensfox-tail brome
Distribution: Chiefly east of the Cascades in Washington; central Washington south to California, east to Idaho, Utah and Arizona.
Habitat: Common weed on overgrazed land, waste areas.
Origin: Introduced
Flowers: May-June
Growth Duration: Annual
Bromus secalinusrye brome
Distribution: Occurring on both sides of the Cascades in Washington; widely distributed throughout North America.
Habitat: Disturbed, open ground.
Origin: Introduced
Flowers: June-July
Growth Duration: Annual
Bromus sitchensisAlaska brome, Sitka brome
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Great Plains
Habitat: Dry to moist open areas from lowlands to subalpine.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. aleutensis – Aleut brome
var. carinatus – California brome
var. marginatus – large mountain brome
var. polyanthus – smooth brome
var. sitchensis – Sitka brome
Bromus squarrosuscorn brome
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east in scattered locations to the Atlantic Coast.
Habitat: Open, disturbed areas including fields, meadows, and forest openings.
Origin: Introduced from Eurasia
Flowers: June-July
Growth Duration: Annual
Bromus sterilispoverty brome
Distribution: Southern British Columbia south to California, and in the Rocky Mountains and eastern United States.
Habitat: Roadsides and waste places.
Origin: Introduced
Flowers: May - July
Growth Duration: Annual
Bromus suksdorfiiSuksdorf's brome
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Bromus tectorumsoft brome, cheatgrass, cheat grass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Baja California, Mexico, east across North America to the Atlantic Coast.
Habitat: Sagebrush desert, grasslands, prairies, meadows, balds, roadsides, wastelots, and other distrubed open areas from low to middle elevations.
Origin: Introduced from Europe
Flowers: March-June
Growth Duration: Annual
Bromus vulgarisColumbian brome
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia south along the coast to northern California, east to Alberta, Montana and Wyoming.
Habitat: Shaded to open woods or moist to dry banks, from near sea level to mountain meadows and dry, rocky slopes at 6000' elevation.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Calamagrostis canadensisbluejoint reedgrass
Distribution: Alaska to Quebec, south through the United States except for the Deep South
Habitat: Wet places, sea level to mid-elevations in the mountains
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
var. canadensis – bluejoint reedgrass
Calamagrostis howelliiHowell's reedgrass
Origin: Native
Flowers: June - Early July
Growth Duration: Perennial
Calamagrostis nutkaensisNootka reedgrass
Habitat: In coastal areas in wetlands, forest openings, salt- and freshwater beaches and dunes, and cliffs.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Calamagrostis purpurascenspurple reedgrass
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
Calamagrostis rubescenspinegrass
Distribution: British Columbia to California, east to Alberta, Montana and Colorado
Habitat: Dry to moist areas, open sagebrush flats to timbered slopes, moderate to mid-elevations in the mountains
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
Calamagrostis strictaslimstem reedgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Atlantic Coast.
Habitat: Wetlands.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. inexpansa – narrow-spiked reedgrass
ssp. stricta – narrow-spiked reedgrass
Calamagrostis tacomensisRainier reedgrass
Distribution: Endemic to the Olympic Mountains and Cascade Range in Washington.
Habitat: Montane to alpine meadows, seeps, and rocky slopes.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Calamagrostis tweedyiCascade reedgrass
Distribution: Occurring chiefly east of the Cascades crest in central Washington; central Washington to southern Oregon, east to Idaho and Montana.
Habitat: Moist meadows and subalpine slopes, usually in forest edge or understory.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Calamovilfa gigantea
Origin: Introduced
Calamovilfa longifoliaprairie sandreed
Origin: Introduced
var. longifolia – prairie sandgrass sandreed, prairie sandreed
Cenchrus longispinuslongspine sandbur, mat sandbur
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to Mexico, east to the Atlantic Coast.
Habitat: Sandy river banks and other disturbed, seasonally moist areas.
Origin: Introduced
Flowers: July-September
Growth Duration: Annual
Cinna latifoliaslender wood-reed
Distribution: Alaska to Newfoundland, south on both sides of the Cascades, Washington to California, east to Colorado; also Minnesota to Maine, south to Tennessee
Habitat: Moist woods and meadows, sea level to subalpine
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Coix lacryma-jobiJob's-tears
Origin: Introduced from tropical Asia
Coleanthus subtilismoss grass
Origin: Native?
Flowers: July - October
Growth Duration: Annual
Cortaderia jubatapurple pampas grass
Distribution: Occurring in lowland western Washington; Washington to California.
Habitat: Disturbed, open areas at low elevation
Origin: Introduced from northern South America
Flowers: June-September
Growth Duration: Perennial
Cortaderia selloanapampas grass
Distribution: Occurring in several counties west of the Cascades crest; Washington to California, in scattered states eastward to Atlantic Coast.
Habitat: Disturbed, open soil of wastelots, abandoned fields, and roadsides at low elevations, often near coast.
Origin: Introduced from central South America
Flowers: May-July
Growth Duration: Perennial
Corynephorus canescensgray club-awn grass
Origin: Introduced
Growth Duration: Annual
Crypsis alopecuroidesfoxtail pricklegrass
Distribution: Occurring in the south-central areas of Washington;
Habitat: Sandy soils around drying lake margins and other seasonally moist, disturbed, open areas.
Origin: Introduced from n. Africa and Eurasia
Flowers: April-July
Growth Duration: Annual
Crypsis vaginifloramodest pricklegrass
Origin: Introduced from the western Mediterranean
Cynodon dactylonbermuda grass
Distribution: Common in the warmer portion of the United States, California to Florida; occasional in the Pacific Northwet.
Habitat: A weed of lawns, partures and railroad tracks.
Origin: Introduced
Flowers: June - September
Growth Duration: Perennial
Cynosurus cristatuscrested dogtail
Distribution: Introduced in scattered locations west of the Cascades in Washington and Oregon, and in California and Idaho.
Habitat: Waste places, old meadows, roadsides.
Origin: Introduced
Flowers: June - July
Growth Duration: Perennial
Cynosurus echinatusbristly dog's-tail grass
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Weed of waste places.
Origin: Introduced from Eurasia
Flowers: May - July
Growth Duration: Annual
Dactylis glomerataorchard grass
Distribution: Distributed widely throughout Washington; distributed widely throughout North America.
Habitat: Disturbed areas such as meadows, fields, roadsides, and forest edges; common forage plant; also planted in logged areas in the mountains.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial
Danthonia californicaCalifornia oatgrass
Distribution: British Columbia south on both sides of the Cascades to California, east to Montana and New Mexico.
Habitat: Open, grassy meadows to rocky ridges, from coastal prairies to mid-elevations in the mountains, often with ponderosa pine.
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Danthonia decumbenscommon heath-grass, mountain heath-grass
Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern British Columbia to California; also in northeastern Canada.
Habitat: Marshy margins, dunes, dry meadows, damp, disturbed ground.
Origin: Introduced from Europe
Flowers: July-September
Growth Duration: Perennial
Danthonia intermediatimber oatgrass
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Danthonia spicatapoverty oatgrass
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia south on both sides of the Cascades to Oregon, east to Newfoundland and eastern United States.
Habitat: Sandy to rocky soil in dry woods and fairly dry meadows.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Danthonia unispicatafew-flower oatgrass, one-spike oatgrass
Distribution: British Columbia south on both sides of the Cascades to California, east to Alberta and Colorado.
Habitat: Dry to occasionally moist prairies, foothills, and open parks and ridges in mountain forests.
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Deschampsia cespitosatufted hairgrass
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to the northern Great Plains, Great Lakes region, and eastern North America.
Habitat: From coastal marshes and moist prairies to alpine ridges, talus slopes, mountain meadows, and moist areas in the mountains in general.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Deschampsia danthonioidesannual hair-grass
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to California, east to the the Rocky Mountains; apparently introduced in Alaska, Yukon Territory, Arizona, New Mexico, and the eastern U.S.; disjunct in Chile and Argentina.
Habitat: Mesic to damp open slopes, ledges, vernal pools, scablands, stream banks, and roadsides.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Deschampsia elongataslender hair-grass
Distribution: Occurring on both sides of the Cascades in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Moist sandy or gravelly banks and slopes, and borders of streams and lakes.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Dichanthelium acuminatumhairy perennial panicgrass
Distribution: Southern British Columbia south along the coast to California; east of the Cascades mainly along water courses or around springs in the mountains, east to Montana and Wyoming.
Habitat: Rocky or sandy river banks or lake margins to open woods, marshy areas or dry prairies, from sea level to high elevation in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. fasciculatum – hairy panicgrass
Dichanthelium oligosanthesScribner's perennial panicgrass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia south on both sides of the Cascades to northern California, east to Idaho, Montana and Utah, also in eastern North America.
Habitat: Dry prairies or rocky areas to sandy stream banks.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
ssp. scribnerianum – Scribner's panicgrass witchgrass
Digitaria ischaemumsmooth crabgrass
Distribution: Most of southern Canada, and all of the United States except the extreme southeast and southwest.
Habitat: Lawns, roadsides and wastland, usually where moist.
Origin: Introduced from Eurasia
Flowers: July - September
Growth Duration: Annual
Digitaria sanguinalishairy crabgrass
Distribution: A weed in most of the United States.
Habitat: Lawns, gardens, and wasteland.
Origin: Introduced from Eurasia
Flowers: July - October
Growth Duration: Annual
Diplachne fuscaclustered salt-grassprangletop, loose-flowered sprangletop
Distribution: Occurring in a few scattered locations chiefly east of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Disturbed areas at low elevations.
Origin: Native
Flowers: August-September
Growth Duration: Annual, Perennial
ssp. fascicularis – bearded sprangletop
Distichlis spicataalkaline grass, coastal salt grass
Distribution: Vancouver Island, British Columbia, south to California; also along the east coast of the United States from Canada to Florida and Texas.
Habitat: Coastal beaches and salt marshes.
Origin: Native
Flowers: June - September
Growth Duration: Perennial
Echinochloa colonaawnless barnyard grass, or jungle-rice
Origin: Introduced from the tropics
Growth Duration: Annual
Echinochloa crus-gallibarnyard grass, or large barnyard grass
Distribution: Found throughout southern Canada and most of the United States.
Habitat: Cultivted fields and wasteland, usually where moist, especially along irrigation ditches.
Origin: Introduced from Eurasia
Flowers: June - October
Growth Duration: Annual
Echinochloa crus-pavonisguleaf barnyard-grass
Origin: Introduced
var. crus-pavonis – gulf barnyard grass
Echinochloa muricataAmerican barnyard-grass
Origin: Native?
Growth Duration: Annual
var. microstachya – American barnyard grass, or watergrass
Eleusine indicagoosegrass
Distribution: Uncommon weed in western Oregon; more common in California and eastern United States.
Habitat: Waste ground and roadsides.
Origin: Introduced from Africa
Flowers: July - August
Growth Duration: Annual
Eleusine tristachya
Origin: Introduced
×Elyhordeum macounii
Origin: Native
×Elyleymus aristatus
Origin: Native
Elymus albicansMontana wild rye
Origin: Native
Growth Duration: Perennial
Elymus canadensisCanadian wild rye
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east to Quebec, North Carolina and Texas
Habitat: Streambanks and thickets on sandy, dry to moist soil, and in disturbed areas.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. canadensis – Canadian wild rye, nodding wild rye
Elymus curvatusbeardless wild rye, awnless wildrye
Origin: Native
Elymus elymoidesbottlebrush, squirreltail
Distribution: British Columbia south to southern California, east to Alberta and Texas.
Habitat: Dry and rocky to moist habitats, from along the coast to inland desert plains and prairies, and in the mountains to above tree line.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
ssp. brevifolius – longleaf squirreltail
ssp. elymoides – bottlebrush squirreltail, California squirreltail
ssp. hordeoides – bottlebrush squirreltail
Elymus glaucusblue wild-rye
Distribution: Southern Alaska south to California, east to Ontario and Indiana.
Habitat: Prairies, open woods, and dry to moist hillsides, from the lowlands to mid-elevations in the mountains.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
ssp. glaucus – blue wildrye
ssp. virescens – blue wildrye
Elymus ×hansenii
Origin: Native
Growth Duration: Perennial
Elymus hirsutusboreal wild rye
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Elymus lanceolatus
Origin: Native
Growth Duration: Perennial
ssp. lanceolatus – thick-spiked wheatgrass
ssp. psammophilus – sand-dune wheatgrass
ssp. riparius – stream bank wheatgrass
Elymus multisetusbig squirreltail
Origin: Native
Flowers: May - August
Growth Duration: Perennial
Elymus ×pseudorepensfalse quackgrass
Origin: Native
Growth Duration: Perennial
Elymus repenscreeping wild rye
Distribution: Native to Eurasia; Alaska to Greenland and south to California, Texas, and North Carolina.
Habitat: Disturbed, open areas.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial
Elymus scribneriScribner's wild rye
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Elymus trachycaulusslender wheatgrass
Origin: Native
Growth Duration: Perennial
ssp. trachycaulus – bearded wheatgrass
Elymus violaceusarctic wheatgrass, bearded wheatgrass
Origin: Native
Growth Duration: Perennial
Elymus wawawaiensiswawawai wild rye
Origin: Native
Growth Duration: Perennial
Eragrostis cilianensisstinkgrass
Distribution: Central Washington south ot California, east to Maine.
Habitat: Disturbed areas and waste land, and along streams and pond margins.
Origin: Introduced from Europe
Flowers: June - October
Growth Duration: Annual
Eragrostis curvulaweeping lovegrass
Distribution: In scattered locations across Washington; occurring from West to East Coast of U.S., typically in the southern half of the country.
Habitat: Distrubed areas where open and forest edge.
Origin: Introduced from southern Africa
Flowers: June-July
Growth Duration: Perennial
Eragrostis hypnoidesteal love grass
Distribution: In Washington, chiefly west of the Cascades, and along the Columbia and Snake Rivers; widespread in central and eastern United States.
Habitat: Mud flats along streams, ponds and lakes.
Origin: Native
Flowers: June - September
Growth Duration: Annual
Eragrostis lutescenssix-weeks love grass
Origin: Native
Flowers: July - October
Growth Duration: Annual
Eragrostis mexicanaMexican lovegrass
Origin: Introduced
Growth Duration: Annual
ssp. virescens – Mexican lovegrass, orcutt's lovegrass
Eragrostis minorlittle lovegrass
Origin: Introduced from Europe
Growth Duration: Annual
Eragrostis pectinaceatufted lovegrass
Origin: Native
Flowers: June - September
Growth Duration: Annual, Perennial
var. pectinacea – purple eragrostis, tufted eragrostis
Eragrostis pilosaIndia lovegrass
Origin: Introduced
Flowers: October
Growth Duration: Annual
var. pilosa – India lovegrass
Eremopyrum triticeumannual false wheatgrass
Distribution: Occurring in scattered locations east of the Cascades crest in Washington; British Columbia to Arizona, east to the Rocky Mountains and Great Plains.
Habitat: Dry wasteland, disturbed areas.
Origin: Introduced
Flowers: May-July
Growth Duration: Annual
Festuca brachyphyllaalpine fescue
Origin: Native
Growth Duration: Perennial
ssp. brachyphylla – alpine fescue
Festuca campestrisprairie fescue
Origin: Native
Growth Duration: Perennial
Festuca filiformisfine-leaf sheep fescue
Origin: Introduced from Europe
Flowers: May - August
Growth Duration: Perennial
Festuca idahoensisbluebunch fescue, Idaho fescue
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Grasslands and sagebrush desert to dry mountain slopes, occasionally to the subalpine.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Festuca occidentaliswestern fescue
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to southwestern Alberta and Wyoming; disjunct in the Great Lakes area.
Habitat: Forest understory, edges, and openings to rocky slopes.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Festuca ovinasheep fescue
Origin: Introduced
Growth Duration: Perennial
Festuca roemeriRoemer's fescue
Distribution: Chiefly west of the Cascades crest in Washington; British Columbia south to California.
Habitat: Meadows, grasslands, balds and forest openings mostly at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Festuca rubrared fescue
Origin: Both native and introduced
Flowers: June - August
Growth Duration: Perennial
ssp. juncea – rock fescue
ssp. mediana – dune red fescue
ssp. rubra – red fescue
Festuca saximontanaRocky Mountain fescue
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Lakes region, and northeastern North America, also in Far East Russia.
Habitat: Montane and subalpine meadows and open forest.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. purpusiana – Rocky Mountain fescue
Festuca subulatabearded fescue
Origin: Native
Flowers: Late May - Early June
Growth Duration: Perennial
Festuca subulifloracrinkle-awn fescue
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to California.
Habitat: Shady sites in dry to moist, lowland to montane forest.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Festuca trachyphyllahard fescue
Origin: Introduced
Growth Duration: Perennial
Festuca valesiacaValais fescue
Origin: Introduced
Festuca viridulagreen-leaf fescue
Distribution: British Colubia south to California, east to Alberta and Montana.
Habitat: Subalpine slopes, rock slides, and meadows to well above timberline.
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Festuca washingtonicaWashington fescue
Distribution: Occurring east of the Cascades crest in Washington; Southern British Columbia Washington.
Origin: Native
Growth Duration: Perennial
Glyceria borealissmall floating manna grass
Distribution: Alaska east to Newfoundland, south to California and New Mexico.
Habitat: Swamps, wet meadows, and stream margins, often growing in 1-3 feet of water.
Origin: Native
Flowers: May - October
Growth Duration: Perennial
Glyceria canadensisCanada mannagrass, rattlesnake mannagrass
Origin: Introduced
var. canadensis – rattlesnake manna grass
Glyceria declinatalow glyceria
Origin: Introduced
Glyceria elatatall mannagrass
Distribution: British Columbia south on both sides of the Cascades to California, east to Montana and New Mexico.
Habitat: Lake margins, stream banks, moist mountain meadows and other wet areas.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Glyceria fluitanswater mannagrass
Origin: Introduced
Glyceria grandisAmerican mannagrass
Distribution: Alaska south to Oregon, chiefly east of the Cascades; east to northeast United States and south to Virginia and New Mexico.
Habitat: Sloughs, damp meadows and stream borders.
Origin: Native
Flowers: Late June - Early August
Growth Duration: Perennial
var. grandis – reed mannagrass
Glyceria leptostachyaslender-spike manna grass
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Glyceria maximatall mannagrass
Origin: Introduced
Glyceria ×occidentalisnorthwestern manna grass
Origin: Native
Flowers: May - June
Growth Duration: Perennial
Glyceria striatafowl manna grass
Distribution: Alaska south to northern California, east to Newfoundland and Florida.
Habitat: Wet places, bogs, and mountain meadows.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Graphephorum wolfiibeardless false oat
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Hesperostipa comataneedle-and-thread
Distribution: British Columbia south on the east side of the Cascades to California, east to Ontario and Texas.
Habitat: Plains and prairies to forested areas in the mountains.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
ssp. comata – needle and thread
ssp. intermedia – Tweedy's needlegrass
Hierochloe occidentalisCalifornia sweet grass, California sweetgrass
Origin: Native
Hierochloe odoratahairy sweetgrass, vanillagrass
Distribution: Occurring in scattered locations across Washington; Alaska south to Washington, east across the northern half of North America to the Atlantic Coast.
Habitat: Wet meadows and marshes.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Holcus lanatuscommon velvet grass
Distribution: Occurring chiefly west of the Cascades crest and east in the Columbia River Gorge in Washington; Alaska to California, east across much of North America to the Atlantic Coast.
Habitat: Balds, prairies, roadsides, meadows, lawns, wastelots, and other disturbed open areas.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Perennial
Holcus molliscreeping softgrass, creeping velvet-grass
Origin: Introduced
ssp. mollis – creeping velvet grass
Hordeum brachyantherummeadow barley
Distribution: Alaska south to California, east to Montana and Colorado.
Habitat: Ocean beaches to mountain meadows,usually where moist, but also from dry sagebrush desert to rocky ridges.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
ssp. brachyantherum – meadow barley
Hordeum depressumdwarf barley
Distribution: Introduced from Vancouver Island, British Columbia, south on both sides of the Cascades to southern California, east to western Idaho.
Habitat: A weed of waste areas, especially where moist.
Origin: Native
Flowers: April - June
Growth Duration: Annual
Hordeum jubatumfoxtail barley
Distribution: Alaska south on both sides of the Cascades to California, east across Canada to the Atlantic Coast, south to Mexico.
Habitat: Common weed of dry to moist soil, from sagebrush desert to grasslands and mountain forests, often abundent in disturbed areas.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
ssp. jubatum – foxtail barley
Hordeum marinumMediterranean barley
Origin: Introduced
Growth Duration: Annual
ssp. gussoneanum – Mediterranean barley
Hordeum murinummouse barley, smooth barley, wall barley
Distribution: Uncommon weed in the United States, occasional in southern British Columbia and western Washington.
Habitat: Disturbed soil and wasteland.
Origin: Introduced
Flowers: June - July
Growth Duration: Annual
ssp. glaucum – mouse barley
ssp. leporinum – mouse barley
ssp. murinum – mouse barley
Hordeum pusillumlittle barley
Distribution: Eastern Washington south to southern California, east to the Atlantic Coast.
Habitat: Grasslands to desert areas, often on saline soils and wasteland.
Origin: Native
Flowers: April - June
Growth Duration: Annual
Hordeum vulgarebarley
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Old fields, wasteland, roadsides, and other disturbed areas where escaped from cultivation.
Origin: Introduced
Flowers: May-June
Growth Duration: Annual
ssp. vulgare – common barley
Koeleria macranthaKoeler's prairie grass, prairie Junegrass
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to northern Mexico, east across North America to the Atlantic Coast except in the southeastern U.S.
Habitat: Sagebrush deserts, prairies, and open forests to subalpine ridges, mostly on sandy to rocky soil.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Leersia oryzoidesrice cut grass
Distribution: Occurring on both sides of the Cascades in Washington; British Columbia east to the Atlantic Coast, south throughout the U.S.
Habitat: Wet places, often in fairly deep water.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Leymus cinereusGreat Basin lyme grass
Distribution: East of the Cascades in Washington; central and western North America.
Habitat: Sagebrush-steppe, arid grasslands, forest edges, and other dry, open areas in the intermountain west.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Leymus condensatusgiant wildrye
Origin: Native
Leymus flavescenssand lyme grass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Leymus mollisAmerican dunegrass
Distribution: Occurring west of the Cascades crest in Washington along the immediate marine coastline; Alaska to California, east across Canada to the Great Lakes region and northeastern North America.
Habitat: Coastal sand dunes, marshes, and headlands, where tolerant of salt water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. mollis – yellow ryegrass
Leymus racemosusmammoth lyme grass, mammoth wildrye
Distribution: Occurring east of the Cascades crest in Washington; central Washington to north-central Oregon, east to Wyoming.
Habitat: Sandy areas in sagebrush flats and plains.
Origin: Introduced from Eurasia
Flowers: July-August
Growth Duration: Perennial
Leymus triticoidesbeardless lyme grass, beardless wildrye
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and Texas.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Leymus ×vancouverensisVancouver wildrye
Origin: Native
Growth Duration: Perennial
Lolium multiflorumannual ryegrass, Italian ryegrass, perennial ryegrass
Distribution: Introduced and well established in much of temperate North America.
Habitat: Roadsides and waste ground.
Origin: Introduced
Flowers: May - July
Growth Duration: Biennial, Perennial
Lolium perenneEnglish ryegrass, perennial ryegrass
Distribution: Commonly cultivated as a forage plant; escaped and well established in the Pacific Northwest.
Habitat: Old fields, roadsides, and waste places.
Origin: Introduced
Flowers: May - July
Growth Duration: Perennial
Lolium persicumPersian ryegrass
Lolium temulentumdarnel, tare
Origin: Introduced
Flowers: May - June
Growth Duration: Annual
ssp. temulentum – darnel
Melica aristatabearded melic grass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Melica bulbosaonion grass
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Melica ciliatasilky melic
Origin: Introduced
Melica fugaxsmall melic grass
Origin: Native
Flowers: May - Early July
Growth Duration: Perennial
Melica harfordiiHarford's melic grass
Origin: Native
Flowers: Late May - July
Growth Duration: Perennial
Melica smithiiSmith's melic grass
Distribution: Slouthern British Columbia south to Oregon, east to Alberta and Wyoming.
Habitat: Moist woods.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Melica spectabilisshowy melic grass
Distribution: Southern British Columbia south to northern California chiefly east of the Caascade crest, east to Montana and Colorado.
Habitat: Usually in moist, loamy soil in meadows and open parks in mountain forests, but also dry to wet meadowlands and open forests to subalpine ridges.
Origin: Native
Flowers: Late May - July
Growth Duration: Perennial
Melica subulataAlaska oniongrass
Distribution: Southern Alaska south to California, east to Montana and Wyoming.
Habitat: Open slopes to thick, dry or moist woods, from near sea level to mid-elevations in the mountains.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Miscanthus sinensisChinese silvergrass
Origin: Introduced
Molinia caeruleapurple moor grass
Distribution: Known from a single locality in King County where it is persistent; occurring in scattered locations throughout North America.
Habitat: Disturbed areas at low elevation near the coast.
Origin: Introduced
Flowers: May-June
Growth Duration: Perennial
Muhlenbergia andinafoxtail muhly
Origin: Native
Flowers: July - September
Growth Duration: Perennial
Muhlenbergia asperifoliaor alkali muhly, scratchgrass
Distribution: British Columbia south, east of the Cascades, to California, east to Montana and Texas.
Habitat: Dry to moist alkaline places.
Origin: Native
Flowers: June - September
Growth Duration: Perennial
Muhlenbergia filiformispullup muhly
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and Kansas.
Habitat: Moist or wet meadows, shores, seeps, hot springs, and stream banks.
Origin: Native
Flowers: June-August
Growth Duration: Annual
Muhlenbergia glomerataspiked muhly
Origin: Native
Growth Duration: Perennial
Muhlenbergia mexicanawirestem muhly
Origin: Native
Muhlenbergia minutissimaannual muhly, least muhly
Origin: Native
Flowers: July
Growth Duration: Annual
Muhlenbergia richardsonismatted muhly
Distribution: British Columbia south, east of the Cascade crests, to Baja California, east to New Brunswick and New Mexico.
Habitat: Moist to dry lowlands, meadows, mountain prairies and rocky slopes.
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Oryzopsis asperifoliawhite-grain mountain-rice grass
Distribution: British Columbia east to Newfoundland, south to Maine and Montana and the northeast portion of Washington.
Habitat: Open coniferous woods.
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Panicum capillarewitchgrass
Distribution: Introduced and weedy in much of the United States and southern Canada.
Habitat: Moist and irrigated areas, along streams and around ponds.
Origin: Native
Flowers: June - September
Growth Duration: Annual
ssp. capillare – or common panicgrass, witchgrass
Panicum dichotomiflorumfall panicum
Distribution: Native in most of central and eastern United States; occasionally introduced in Washington.
Habitat: Waste ground.
Origin: Introduced
Flowers: May - September
Growth Duration: Annual, Perennial
ssp. dichotomiflorum – fall panicum, western witchgrass
Panicum giblinianum
Origin: Native
Panicum miliaceummillet
Distribution: Introduced and cultivated in many parts of the United States; occasionally escaping and persisting in the Pacific Northwest.
Habitat: Abandoned fields, roadsides, waste ground.
Origin: Introduced
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
Parapholis incurvasicklegrass
Origin: Introduced
Pascopyrum smithiiwestern-wheat grass
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Paspalum distichumknotgrass, Thompsongrass
Distribution: Occurring chiefly along the lower Columbia River corridor in Washington; occurring in most of western North America and the southeastern U.S.
Habitat: Along ditches and streams where the soil is moist much of the season.
Origin: Native
Flowers: August-October
Growth Duration: Perennial
Pennisetum glaucumpearl millet
Origin: Introduced
Growth Duration: Annual
Pennisetum setaceumtender fountaingrass
Origin: Introduced from the eastern Mediterranean
Phalaris arundinaceareed canary grass
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
Origin: Introduced
Flowers: June - August
Growth Duration: Annual
Phalaris paradoxaMediterranean canary grass
Origin: Introduced
Flowers: June - August
Growth Duration: Annual
Phleum alpinummountain Timothy
Distribution: Alaska east to Newfoundland, south in the subalpine regions of the mountains in most of western United States.
Habitat: Streambanks and meadows at higher elevations.
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
Phleum pratenseTimothy
Distribution: Both sides of the Cascades in Washington; throughout North America.
Habitat: Disturbed areas, especially moist, open meadows, from coast to midmontane.
Origin: Introduced
Flowers: May-July
Growth Duration: Perennial
ssp. pratense – common Timothy
Phragmites australiscommon reed
Distribution: In scattered locations throughout many areas of Washington; widely distributed throughout North America; circumboreal.
Habitat: Disturbed areas, including roadsides, often where wet or seasonally moist.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
ssp. americanus – common reed
ssp. australis – common reed
Piptatheropsis exigualittle mountain-ricegrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia, south east of the Cascade crest 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
Pleuropogon refractusnodding false semaphore grass
Distribution: Southern British Columbia south in both the Olympics and Cascades of Washington, and the Cascades and coastal mountains of Oregon, to Mendocino County, 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
Origin: Native
ssp. alpina – alpine blue grass
Poa annuaannual blue grass
Distribution: Common weed throughout the Pacific Northwest.
Habitat: Lawns, gardens, roadsides, and waste ground to open woods.
Origin: Introduced
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
Poa bolanderiBolander's blue grass
Origin: Native
Flowers: July - 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 blue grass
Distribution: Alaska east to Newfoundland, south to most of the United States; common in the Pacific Northwest.
Habitat: Waste ground, roadsides, and gardens to open woods and meadows, usually where moist.
Origin: Introduced
Flowers: June - August
Growth Duration: Perennial
Poa confiniscoastline blue grass
Distribution: VAncouver Island, British Columbia, south along the coast to San Francisco, California.
Habitat: Coastal sand dunes.
Origin: Native
Flowers: May - June
Growth Duration: Perennial
Poa curtifolialittle mountain blue grass
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Poa cusickiiCusick's bluegrass
Distribution: British Columbia south in the Olympics and Cascades to California, east to Saskatchewan and Colorado.
Habitat: Sagebrush plains to alpine meadows and ridges.
Origin: Native
Flowers: June - 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
Origin: Native
Flowers: May - August
ssp. longiligula – muttongrass
Poa glauca
Origin: Native
ssp. rupicola – timberline bluegrass
Poa howelliiHowell's bluegrass
Distribution: Occurring west of the Cascades crest in Washington and in the Columbia River Gorge; 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
Origin: Introduced
Poa interiorinterior bluegrass, woods blue grass
Origin: Native
Poa laxifloraloose-flower blue grass
Distribution: Southern Alaska south to the Olympic Peninsula of Washington and Multnomah, Clackamus and Benton Counties, Oregon.
Habitat: Moist woods to rocky, open slopes, from near sea level to lower elevations in the mountains.
Origin: Native
Flowers: June
Growth Duration: Perennial
Poa leibergiiLeiberg's blue grass
Origin: Native
Flowers: Late March - May
Growth Duration: Perennial
Poa leptocomamarsh blue grass
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
Poa lettermaniiLetterman's blue grass
Origin: Native
Flowers: August
Growth Duration: Perennial
Poa macranthasand-dune blue grass
Distribution: Southern Vancouver Island and the islands of Puget Sound, south along the coast to Mendocino County, California.
Habitat: Chiefly on sand dunes.
Origin: Native
Flowers: April - July
Growth Duration: Perennial
Poa marcidawithered blue grass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Poa ×multnomae
Origin: Native
Poa nemoraliswoodland bluegrass
Origin: Introduced
Flowers: May - August
Growth Duration: Perennial
Poa nervosaHooker's blue grass
Origin: Native
Flowers: April - August
Growth Duration: Perennial
Poa palustrisfowl blue grass
Distribution: Introduced and widely distributed through Alaska and Canada, south to northern California and Virginia.
Habitat: Sea level to open meadows and forested areas in the mountains, always where moist.
Origin: Introduced
Flowers: May - August
Growth Duration: Perennial
Poa paucispiculaAlaska blue grass
Origin: Native
Flowers: Late June - August
Growth Duration: Perennial
Poa pratensisKentucky bluegrass
Distribution: Throughout Washington; common throughout temperate world.
Habitat: Moist, distrurbed areas at from the coast to middle elevations.
Origin: Both native and introduced
Flowers: April - October
Growth Duration: Perennial
ssp. pratensis – Kentucky blue grass
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
Origin: Native
var. stenantha – narrow-flower blue grass
Poa suksdorfiiwestern blue grass
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Poa trivialisrough-stalk blue grass
Origin: Introduced
Flowers: May - July
Growth Duration: Perennial
Poa unilateralissea-bluff bluegrass
Origin: Native
ssp. pachypholis – San Francisco blue grass
Poa wheeleriWheeler's blue grass
Origin: Native
Flowers: April - August
Growth Duration: Perennial
Podagrostis aequivalvisarctic bent
Origin: Native
Podagrostis humilisalpine bent, mountain bent
Origin: Native
Podagrostis thurberianaThurber's bent
Origin: Native
Polypogon australisChilean rabbit's-foot grass
Origin: Introduced
Growth Duration: Perennial
Polypogon fugaxAsia Minor bluegrass
Origin: Introduced
Polypogon interruptusditch rabbit's-foot grass
Origin: Introduced
Flowers: June - August
Growth Duration: Perennial
Polypogon maritimusMediterranean rabbitsfoot grass
Distribution: Known from Klickitat County in WA; Washington to California, east to Nevada; also in southeastern North America.
Habitat: Shoreline of ponds, lakes and rivers.
Origin: Introduced
Flowers: June-August
Growth Duration: Annual
Polypogon monspeliensisannual rabbit's-foot grass
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout much of North America.
Habitat: Wet to dry waste areas, including vernal pools where the water is brackish.
Origin: Introduced
Flowers: May-August
Growth Duration: Annual
Polypogon viridisbeardless rabbit's-foot grass
Origin: Introduced
Flowers: June - September
Growth Duration: Perennial
Psathyrostachys junceaRussian-wild rye
Origin: Introduced
×Pseudelymus saxicola
Origin: Native
Pseudoroegneria spicata?bluebunch wheatgrass
Distribution: British Columbia south, chiefly east of the Cascade crests, but also in the coastal mountains, to California, east to the Dakotas and New Mexico.
Habitat: From the plains to mid-elevations in the mountains.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Pseudosasa japonicaJapanese bamboo
Habitat: Forest edge, roadsides, and other disturbed areas at low elevations where escaping from cultivation.
Origin: Introduced from Asia
Growth Duration: Perennial
Puccinellia distansweeping alkaligrass, European alkali grass
Distribution: Occurring east of the Cascades in Washington; North-central British Columbia south, chiefly east of the Cascades, to California, east through most of Canada and to the east base of the Rockies.
Habitat: Moist soil, especially where alkaline.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial
Puccinellia lemmoniiLemmon's alkali grass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Puccinellia maritimacoast alkaligrass
Origin: Introduced
Puccinellia nutkaensisNootka alkali grass, shining alkali grass
Origin: Native
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 pumiladwarf alkali grass
Origin: Native
Flowers: June - August
Growth Duration: Perennial
Redfieldia flexuosablowout grass
Origin: Introduced from central United States
Sasa palmatabroadleaf bamboo
Distribution: Occurring in the Puget Sound lowlands in Washington; also known from Tennessee.
Habitat: Disturbed lowland areas where escaping from cultivation.
Origin: Introduced
Growth Duration: Perennial
Schedonorus arundinaceustall fescue, tall rye grass
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Meadowlands, fallow fields an ditch banks.
Origin: Introduced
Flowers: May-July
Growth Duration: Perennial
Schedonorus pratensismeadow fescue, meadow rye grass
Distribution: Occurring in scattered localities on both sides of the Cascades crest in Washington; widely distributed throughout North America.
Habitat: Meadows, pastures, roadsides, and other disturbed areas, often where moist
Origin: Introduced
Flowers: May-July
Growth Duration: Perennial
Schizachyrium scopariumbroom bluestem, little bluestem
Distribution: Alberta east to Quebec, south through most of the United States east of the rockies; sparingly introduced in the Pacific Northwest.
Habitat: Prairies and foothills.
Origin: Native?
Flowers: July - August
Growth Duration: Perennial
var. scoparium – broom beardgras, broom bluestem, little bluestem
Sclerochloa duracommon hard grass
Distribution: Sparingly introduced in much of western United States; established in eastern Washington and Oregon.
Habitat: Weed of waste areas.
Origin: Introduced
Flowers: June
Growth Duration: Annual
Scleropoa rigidafern grass
Origin: Introduced
Flowers: June - July
Growth Duration: Annual
Scribneria bolanderiScribner's grass
Origin: Native
Flowers: April - May
Growth Duration: Annual
Secale cerealecultivated rye
Distribution: Widely cultivated, especially in poor, dry soil, often persistent for more than one season.
Habitat: Roadsides and waste ground.
Origin: Introduced
Flowers: May - July
Growth Duration: Annual, Biennial
Secale strictum
Origin: Introduced
Setaria faberiChinese foxtail
Origin: Introduced from China
Growth Duration: Annual
Setaria italicaItalian bristlegrass, foxtail millet
Origin: Introduced from China
Growth Duration: Annual
Setaria pumila
Origin: Introduced
Growth Duration: Annual
ssp. pallide-fusca – yellow foxtail, pigeon grass
ssp. pumila – yellow foxtail
Setaria verticillatahooked bristlegrass, rough bristlegrass
Distribution: Sparingly introduced in the Pacific Northwest; more common in other parts of the United States.
Habitat: Weed of gardens, irrigated areas and wasteland.
Origin: Introduced from Europe
Flowers: August - September
Growth Duration: Annual
Setaria viridis
Distribution: Widely distributed throughout much of Washington; widely distributed throughout much of North America.
Habitat: Disturbed soil and wasteland.
Origin: Introduced from Eurasia
Flowers: June-October
Growth Duration: Annual
var. viridis – green bristlegrass
Sorghum bicolorsorghum
Origin: Introduced from Africa
Growth Duration: Annual, Perennial
Sorghum halepenseJohnson grass
Distribution: Introduced and established in much of the United States; rarely persistent in the Pacific Northwest.
Habitat: Waste ground, especially where moist.
Origin: Introduced from Mediterranean
Flowers: July - October
Growth Duration: Perennial
Spartina alterniflorasaltwater cordgrass, smooth cordgrass
Distribution: Introduced in Pacific County, Washington; common along the Atlantic and Gulf Coasts of the United States.
Habitat: Along the coast in brackish water.
Origin: Introduced from the Atlantic coast of North America
Flowers: August - September
Growth Duration: Perennial
Spartina anglicaEnglish cordgrass
Origin: Introduced from Europe
Growth Duration: Perennial
Spartina densifloraChilean cordgrass
Origin: Introduced from Chile
Growth Duration: Perennial
Spartina gracilisalkali cordgrass
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Spartina patenssaltmeadow cordgrass
Origin: Introduced from the Atlantic Coast of North America
Growth Duration: Perennial
Spartina pectinatafreshwater cordgrass, prairie cordgrass
Distribution: Eastern Washington and Oregon, east to Newfoundland and North Carolina.
Habitat: Ditches, ponds, and fresh-water marshes.
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Spartina ×townsendiiTownsend's cordgrass
Origin: Introduced from Europe
Growth Duration: Perennial
Sphenopholis intermediaslender wedgescale
Origin: Native
Growth Duration: Perennial
Sphenopholis obtusataprairie wedgescale
Origin: Native
Flowers: June - July
Growth Duration: Annual, Perennial
Sporobolus airoidesalkali sacaton
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to California and Mexico, east to the Great Plains; introduced in eastern North America.
Habitat: Mesic or damp slopes and flats, often where alkaline, shores, grasslands, vernal pools, and hot springs at low to middle elevations.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Sporobolus composituscomposite dropseed, tall dropseed
Origin: Native
Growth Duration: Perennial
var. compositus – rough dropseed
Sporobolus cryptandrussand dropseed
Distribution: British Columbia south, east of the Cascades, to southern California, east to Ontario, Maine, and most of the United States except the extreme southeast.
Habitat: Sagebrush desert, especilly where sandy, to the foothills and grassland.
Origin: Native
Flowers: June - July
Growth Duration: Perennial
Sporobolus neglectussmall dropseed
Origin: Native
Flowers: July - September
Growth Duration: Annual
Sporobolus vaginifloruspoverty dropseed
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; British Columbia to Washington and California, east to Idaho and the southwestern U.S.; native from Great Plains east to Atlantic Coast.
Habitat: Roadsides, fields, and other disturbed, open areas.
Origin: Introduced
Flowers: July-September
Growth Duration: Perennial
var. vaginiflorus – poverty dropseed
Taeniatherum caput-medusaemedusa-head
Distribution: Sparingly introduced in east-central Washington; more common on both sides of the Cascades in Oregon, east into southeast Idaho and south into California.
Habitat: Weed of waste ground.
Origin: Introduced
Flowers: May - June
Growth Duration: Annual
Thinopyrum intermediumintermediate wheatgrass
Origin: Introduced
Flowers: June - August
Growth Duration: Perennial
ssp. barbulatum – pubescent wheatgrass
ssp. intermedium – intermediate wheatgrass
Thinopyrum ponticumEurasian wheatgrass
Distribution: Occurring chiefly east of the Cascades crest in Washington; Yukon Territory to California, east to the Great Plains.
Habitat: Disturbed areas including roadsides, wastelots, and agricultural fields.
Origin: Introduced from Eurasia
Flowers: May-June
Growth Duration: Perennial
Torreyochloa pallidapale false manna grass
Distribution: Alaska south along the coast to California, east to Alberta and New Mexico.
Habitat: Wet places, from near sea level to 11,000 feet elevation in mountain meadows.
Origin: Native
Flowers: June - August
Growth Duration: Perennial
var. pauciflora – weak alkaligrass
Tripidium ravennaeravennagrass
Distribution: Occurring east of the Cascades crest in southeastern Washington; southeastern Washington to adjacent Oregon, also in Boise, Idaho; California and sporadically eastward to the Atlantic Coast.
Habitat: Roadsides, fields, and other disturbed, open areas.
Origin: Introduced from Eurasia
Flowers: July-September
Growth Duration: Perennial
Triplasis purpureapurple sandgrass
Origin: Introduced
var. purpurea – purple sandgrass
Trisetum canescenstall false oat
Origin: Native
Flowers: May - July
Growth Duration: Perennial
Trisetum cernuumnodding Trisetum
Origin: Native
Trisetum flavescensyellow false oat
Origin: Introduced
Growth Duration: Perennial
Trisetum spicatumnarrow false oat, spike trisetum
Distribution: Occurring in the mountainous areas on both sides of the Cascades crest throughout Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, further east to the Great Lakes region and eastern North America.
Habitat: Montane forests to alpine slopes in rocky, dry or moist areas.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Triticum aestivumbread wheat
Distribution: Introduced world-wide, but fails to persist more that a few seasons on its own.
Habitat: Cultivated in fields.
Origin: Introduced
Flowers: April - June
Growth Duration: Annual
Vahlodea atropurpureaarctic-hair grass
Distribution: Alaska south to the high mountains of California, east to Newfoundland and New Hamshire.
Habitat: Mountain meadows, streambanks, and lake margins to alpine ridges.
Origin: Native
Flowers: July - August
Growth Duration: Perennial
Ventenata dubiaVentenata
Distribution: Chiefly in the eastern portion of Washington; British Columbia south to California, east to the Rocky Mountains; also in eastern North America.
Habitat: Roadsides, pastures, crop land, and other disturbed sites.
Origin: Introduced
Flowers: June-July
Growth Duration: Annual
Vulpia bromoidesbrome fescue
Distribution: Introduced from southern British Columbia to southern California and Arizona, occasional farther east.
Habitat: From ocean beaches and salt marshes to sagebrush deserts.
Origin: Introduced
Flowers: April - June
Growth Duration: Annual
Vulpia microstachyssmall fescue
Origin: Native
Growth Duration: Annual
Vulpia myurosrattail fescue, rattail six-weeks grass
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout most of North America except for the Great Plains and eastern Canada.
Habitat: Balds, open slopes, grasslands, roadsides, wastelots, and other disturbed open areas
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Vulpia octoflorasix–weeks fescue
Origin: Native
Growth Duration: Annual
var. hirtella – six-weeks fescue
var. octoflora – six-weeks fescue
Zea mayscorn
Origin: Introduced
Growth Duration: Annual
ssp. mays – corn, Indian corn, maize
Zizania palustrisnorthern wild rice
Origin: Introduced
Growth Duration: Annual
var. palustris – northern wild rice