Vascular Plants

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


Browse by scientific name:

A, B, C, D, E, F, G, H, I, J, K, L, M, N, O, P, Q, R, S, T, U, V, W, X, Y, Z
Scientific names beginning with T:
Taeniatherum caput-medusaemedusa-head
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to the Rocky Mountains; also in eastern North America.
Habitat: Sagebrush desert, fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: April-June
Growth Duration: Annual
Tamarix chinensis × Tamarix ramosissimahybrid salt cedar, hybrid saltcedar, hybrid tamarisk
Distribution: Occurring east of the Cascades crest in Washington, where known only from Walla Walla County; expected to occur wherever the two parent species co-occur.
Habitat: Riparian zones in arid areas.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial
Tamarix parviflorasmall-flower salt cedar, small-flower saltcedar, small-flower tamarisk
Distribution: Occurring chiefly east of the Cascades crest in Washington; south-central British Columbia to California, east to the southern Rocky Mountains and southern Great Plains.
Habitat: Mostly in riparian areas in arid regions.
Origin: Introduced from southern Europe and northern Africa
Flowers: May-June
Growth Duration: Perennial
Tamarix ramosissimasalt cedar, saltcedar, tamarisk
Distribution: Occurring east of the Cascades crest in Washington; south-central British Columbia to California, east to the Great Plains and southeastern U.S.
Habitat: Riparian zones and other moist to wet areas in arid regions.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Perennial
Tanacetum balsamitacostmary
Distribution: Occurring scattered locations on both sides of the Cascades crest in Washington; southern British Columbia to California, east across much of North America to the Atlantic Coast.
Habitat: Roadsides and other waste places.
Origin: Introduced from Asia
Flowers: August-September
Growth Duration: Perennial
Tanacetum bipinnatumcamphor tansy, dune tansy
Distribution: Occurring west of the Cascades crest along the coast of Washington; Alaska to California, east across Canada to the Great Lakes region and northeastern North America.
Habitat: Sand dunes along the coast.
Origin: Native
Flowers: May-September
Growth Duration: Perennial
Tanacetum partheniumfeatherfew, feverfew
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; British Columbia to Nevada, east to the Rocky Mountains.
Habitat: Roadsides, fields, wastelots, and other distrubed areas at low elevations.
Origin: Introduced from Europe
Flowers: June-November
Growth Duration: Perennial
Tanacetum vulgarecommon tansy
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields, shorelines, wastelots, and other disturbed, open areas at low to middle elevations.
Origin: Introduced from Europe
Flowers: July-October
Growth Duration: Perennial
Taraxacum alaskanumdwarf alpine dandelion
Distribution: Occuring only in North Cascades in Washington; Alaska to Washington, also in Russian Far East.
Habitat: Rocky, exposed areas in alpine habitatas.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Taraxacum ceratophorumhorned dandelion
Distribution: Occurring in mountainous areas on both sides of the Cascades crest in Washington; Northwest Territory to Washington, east to Rocky Mountains; east across Canada to Greenland.
Habitat: Rocky, open areas in the alpine.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Taraxacum erythrospermumred-seeded dandelion
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: Meadows, grasslands, prairies, and other open areas, typically where some level of disturbance present.
Origin: Introduced from Eurasia
Flowers: April-October
Growth Duration: Perennial
Taraxacum officinalecommon dandelion
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Common in disturbed areas, fields, lawns, from the coast to the alpine.
Origin: Introduced from Europe
Flowers: March-October
Growth Duration: Perennial
Taraxacum scopulorumalpine dandelion
Distribution: Likely restricted to the North Cascades in Washington; British Columbia to Washington, east to Alberta, Montana, Idaho, Utah, Wyoming, and Colorado,
Habitat: Rocky sites in the alpine.
Flowers: June-September
Growth Duration: Perennial
Taraxia subacaulislong-leaf evening-primrose
Distribution: Occurring east of the Cascades in Washington; Washington to California, east to Montana and Colorado.
Habitat: Meadows, benchland, and stream banks, from sagbrush plains to moderate elevations in the mountains, usually where dry by late summer.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Taraxia tanacetifoliatansy-leaf evening-primrose
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Idaho and Nevada
Habitat: Dry, often sandy or gravelly ground, low to moderate elevations
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Tauschia stricklandiiStrickland's tauschia, Strickland's umbrella-wort
Distribution: Occurring on west side of Mount Rainier National Park and nearby Yakima County in WA; also in Multnomah and Lincoln counties in Oregon.
Habitat: Moist meadows, forest openings and edge at middle elevations.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Taxus baccataEnglish yew
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to western Oregon.
Habitat: Forest edge, fields, and disturbed areas where escaping from cultivation.
Origin: Introduced from Europe
Cones: April-June
Growth Duration: Perennial
Taxus brevifoliaPacific yew, western yew
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to southeastern Alberta, Idaho, western Montana, and northeastern Oregon.
Habitat: Open to deep, usually moist forests, sea level to middle elevations in the mountains
Origin: Native
Cones: August-October
Growth Duration: Perennial
Teesdalia nudicaulisshepherd's cress
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, also in northeastern U.S.
Habitat: Sandy or gravelly soil at low elevations.
Origin: Introduced from Europe
Flowers: March-May
Growth Duration: Annual
Tellima grandiflorafragrant fringecup
Distribution: Occurring chiefly west of the Cascades crest in Washington, but also in northeastern Washington and in the Columbia River Gorge; Alaska to California, east to northern Idaho and western Montana.
Habitat: Common in damp woods, forest edges, and along streams from sea level to middle elevations in the mountains.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Tetradymia canescensgray horsebrush, spineless horsebrush
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to California, east to the Rocky Mountains.
Habitat: Dry, open places in sagebrush.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
Tetragonia tetragonioidesNew Zealand spinach
Distribution: Occurring west of the Cascades crest along the outer coast in Washington; Washington to California, also in eastern North America.
Habitat: Sand dunes, bluffs, margins of coastal wetlands, and disturbed areas.
Origin: Introduced
Flowers: June-August
Growth Duration: Annual, Perennial
Teucrium canadensewestern germander
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Stream banks, lakeshores, and moist bottom lands, mostly at low elevations.
Origin: Native
Flowers: June-September
Growth Duration: Perennial
var. occidentale – Canada germander
Thalictrum dasycarpumpurple meadow-rue
Distribution: Occurring in the northeastern corner of Washington; Alberta to Arizona, east to central North America.
Habitat: Meadowlands and moist woods.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Thalictrum occidentalewestern meadow-rue
Distribution: Occurring on both sides of the Cascades crest in Washington; Yukon Territory to northern California, east to Montana and Colorado.
Habitat: Shady woodlands and forests, from low elevations to mid-elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Thalictrum venulosumveiny-leaf meadow-rue
Distribution: Occurring chiefly east of the Cascades crest in Washington; Yukon Territory to Nevada, Utah, and New Mexico, east to eastern North America.
Habitat: Riparian areas, coniferous forest understory.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Thelypodium howelliiHowell's thelypody
Distribution: Known historically from east of the Cascades crest in central Washington; otherwise northeast Oregon to California.
Habitat: Sagebrush desert.
Origin: Native
Flowers: May-July
Growth Duration: Biennial, Perennial
ssp. howellii – Howell's thelypody
Thelypodium integrifoliumentire-leaved thelypody
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to northern Great Plains.
Habitat: Sagebrush plains to streambanks in the lower mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. integrifolium – entire-leaved thelypody
Thelypodium laciniatumcut-leaf thelypody, thick-leaved thelypody
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to Idaho and Nevada.
Habitat: Rock cliffs and dry, rocky areas.
Origin: Native
Flowers: April-July
Growth Duration: Biennial
Thelypodium milleflorummany flowered thelypody
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to Nevada, east to Idaho.
Habitat: Rock cliffs and dry, rocky areas in sagebrush desert.
Origin: Native
Flowers: April-July
Growth Duration: Biennial
Thelypodium sagittatumslender thelypody
Distribution: Occurring east of the Cascades crest in Washington; Washington to Nevada, east to Montana and Colorado.
Habitat: Sagebrush desert plains to lower mountains.
Origin: Native
Flowers: June-July
Growth Duration: Biennial, Perennial
ssp. sagittatum – sagittate thelypody, slender thelypody
Thermopsis montanamountain buck-bean, mountain golden-banner, mountain golden-pea, mountain thermopsis
Distribution: Occurring on both sides of the Cascades crest in Washington, but only occurring in the far western and eastern counties; British Columbia to California, east to the Rocky Mountains.
Habitat: Sandy, well-drained soil to wet meadowland, low to moderate elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. ovata – slender goldenbanner
Thinopyrum intermediumintermediate wheatgrass
Distribution: Occurring east of the Cascades crest in Washington; Yukon Territory to California, east to the Great Plains.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
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
Thlaspi arvensefanweed, field pennycress
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Weed of waste ground, low to moderate elevations.
Origin: Introduced from Eurasia
Flowers: April-August
Growth Duration: Annual
Thuja plicatacanoe cedar, western red cedar
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to northern California, east to Alberta, Idaho, and Montana.
Habitat: Moist or swampy areas from sea level to mid-elevations in the mountains.
Origin: Native
Cones: April-May
Growth Duration: Perennial
Thymelaea passerinamezereon
Distribution: Occurring east of the Cascades crest, where known from Okanogan County. also in the central U.S.
Habitat: Lake and pond shores, where alkaline.
Origin: Introduced from Eurasia
Flowers: June-August
Growth Duration: Annual
Thymus serpyllum
Origin: Introduced
Thysanocarpus curvipessand fringepod, lacepod
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to Idaho, Colorado, and New Mexico.
Habitat: Uncommon on dry, open hillsides and borders of woodlands.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Tiarella trifoliatathree-leaf foamflower
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Idaho and Montana.
Habitat: Moist woods and stream banks, sea level to mid-elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. laciniata – cut-leaved foamflower
var. trifoliata – three-leaf foamflower
var. unifoliata – simple-leaved foamflower
Tilia cordatasmall-leaved linden
Distribution: Occurring on both sides of the Cascades crest in Washington; in scattered areas across North America, where occasionally escaping from cultivation.
Habitat: Disturbed forest edge, thickets, and other disturbed areas.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Perennial
Tiquilia nuttalliicoldenia, rosette crinklemat, rosette tequilia
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Utah.
Habitat: Sagebrush plains, typically in sand dune areas.
Origin: Native
Flowers: May-August
Growth Duration: Annual
Tolmiea menziesiipiggyback-plant
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California.
Habitat: Moist woods and stream banks, from low to middle elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Tonella floribundagreater baby-innocence, large-flowered tonella
Distribution: Occurring east of the Cascades crest in southern Washington; southern Washington to Oregon, east to Idaho.
Habitat: Open, often rocky places, at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Tonella tenellalesser baby-innocence, small-flowered tonella
Distribution: Occurring chiefly in the Columbia River Gorge in Washington; disjunct in southwestern British Columbia and the northern Olympic Peninsula, otherwise southern Washington to central California.
Habitat: Fairly moist in open to partly shaded places at low elevations.
Origin: Native
Flowers: March-May
Growth Duration: Annual
Tonestus lyalliiLyall's goldenweed, Lyall's serpentweed
Distribution: Occurring in the Olympics and Cascades mountains in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Mountain meadows and rocky slopes, subalpine and alpine.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Torilis arvensisfield hedge-parsley
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; British Columbia to California, east to Idaho and Nevada, widespread from the U.S. midwest to the Atlantic Coast.
Habitat: Roadsides, forest edge, thickets, fields, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: July-September
Growth Duration: Annual
Torilis japonicaJapanese hedge-parsley, upright hedge-parsley
Distribution: Occurring chiefly west of the Cascades crest in Washington; southwestern British Columbia to California, also in south-central and eastern North America.
Habitat: Forest understory and edge, thickets, fields, roadsides, wastelots, and other disturbed areas at low elevations.
Origin: Introduced
Flowers: April-July
Growth Duration: Annual
Torreyochloa pallidapale false manna grass
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: Lowland to subalpine lake and stream margins, bogs, swamps, and marshes.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
var. pauciflora – weak alkaligrass
Townsendia floriferashowy Townsend daisy, showy townsendia
Distribution: Occurring east of the Cascades crest in Washington; Washington to Oregon and Nevada, east to Montana, Wyoming, and Utah.
Habitat: Dry-open places in the plains and foothills, often with sagebrush.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Toxicodendron diversilobumPacific poison-oak
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east to Nevada.
Habitat: Open woods at low elevations.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Toxicodendron radicanswestern poison ivy
Distribution: Occurring east of the Cascades crest in Washington; occurring throughout much of North America, except Alaska, California, southeastern U.S. and northeastern Canada.
Habitat: Generally in the lowlands and foothills and into the lower mountains in open areas or forest edges.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
var. rydbergii – poison-ivy, western poison-ivy
Toxicoscordion paniculatumsand corn, panicled death-camas
Distribution: Occurring east of the Cascades crest in Washington; north-central Washington to California, east to the Rocky Mountains.
Habitat: Grassy slopes, sagebrush desert, and ponderosa or lodgepole pine forest openings.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Toxicoscordion venenosummeadow death-camas, deadly zygadene
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: Grasslands, balds, prairies, and ponderosa pine forest openings, from the coast to middle elevations.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
var. gramineum – common death-camas, grassy death-camas
var. venenosum – coastal death-camas, common death-camas
Tragopogon dubiusyellow salsify
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Roadsides, fields, meadows, wastelots, overgrazed areas, and other disturbed open areas at low to middle elevations.
Origin: Introduced from Europe
Flowers: May-September
Growth Duration: Annual, Biennial
Tragopogon floccosuswoolly goatsbeard
Distribution: Occurring east of the Cascades crest in eastern Washington, where known only from Whitman County. eastern Washington and adjacent western Idaho.
Habitat: Disturbed areas, fields, roadsides.
Origin: Introduced
Flowers: July-August
Growth Duration: Biennial, Perennial
Tragopogon mirusremarkable goatsbeard
Distribution: Occurring east of the Cascades crest in south-central and eastern Washington; eastern Washington and adjacent western Idaho, also occurring in Arizona.
Habitat: Dry, open areas in the foothills.
Origin: Native
Flowers: May-June
Growth Duration: Biennial
Tragopogon miscellushybrid goatsbeard
Distribution: Occurring east of the Cascades crest in eastern Washington; eastern Washington and adjacent Idaho, Wyoming, and Arizona.
Habitat: Fields, roadsides, and other disturbed, open areas.
Origin: Native
Flowers: May-June
Growth Duration: Biennial
Tragopogon porrifoliusoyster plant, purple salsify
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields and waste places, usually where moist.
Origin: Introduced from Europe
Flowers: April-August
Growth Duration: Biennial
Tragopogon pratensisJack-go-to-bed-at-noon, meadow salsify
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields and waste places, usually in slightly moist areas.
Origin: Introduced from Europe
Flowers: May-August
Growth Duration: Biennial
Trautvetteria caroliniensisfalse bugbane, wild bugbane
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, also in central and southeastern U.S.
Habitat: Moist, open woods and stream banks, low to mid-elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Triadenum fraserimarsh St. John's wort
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to southwestern Washington.
Habitat: Peatlands, ditches, sandy shores, floating logs, and cranberry farms.
Origin: Introduced from eastern North America
Flowers: July-September
Growth Duration: Perennial
Triantha occidentaliswestern asphodel, western tofieldia
Distribution: Occurring in the Olympic and Cascade mountains in Washington; British Columbia to California.
Habitat: Moist meadows, bogs and streambanks, mid- to high elevations in the mountains.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
ssp. brevistyla – sticky asphodel, sticky tofieldia
Tribulus terrestrispuncture vine
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Noxious weed of sandy soils and roadsides.
Origin: Introduced from Europe and northern Africa
Flowers: May-September
Growth Duration: Annual
Trichophorum cespitosumtufted club-rush
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to Oregon, east to Montana and Utah; also in eastern North America
Habitat: Sphagnum bogs, marshes, and other very wet places.
Origin: Native
Flowers: July-August
Growth Duration: Perennial
Trichostema oblongummountain bluecurls
Distribution: East of the Cascades crest in Washington; Washington to California, east to Idaho and Nevada.
Habitat: Moist, open places, often on disturbed soil.
Origin: Native
Flowers: July-August
Growth Duration: Annual
Trifolium albopurpureumRancheria clover
Distribution: Known from only a few scattered locations in Klickitat County in Washington; south-central Washington to California, east to Arizona.
Habitat: Cliffs, balds, and forest openings at low to moderate elevations.
Origin: Native
Flowers: May-June
Growth Duration: Annual
Trifolium arvenserabbitfoot clover, hare's foot
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California, east to Montana, further eastward across the northern U.S. and southern Great Plains and Canada to eastern North America.
Habitat: Roadsides, fields, wastelots, and other disturbed open areas.
Origin: Introduced
Flowers: May-July
Growth Duration: Annual
Trifolium aureumgolden clover, greater hop clover, yellow clover
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to Montana and Wyoming; also occurring in most of eastern North America.
Habitat: Roadsides, fields, lawns, railways, wastelots, and other disturbed open sites.
Origin: Introduced
Flowers: June-September
Growth Duration: Annual, Biennial
Trifolium bifidumnotch-leaf clover, Pinole clover
Distribution: Occurring in Klickitat County in Washington; south-central Washington to California.
Habitat: Open woodlands and grassy slopes.
Origin: Native
Flowers: April-June
Growth Duration: Annual
var. decipiens – notchleaf clover, Pinole clover
Trifolium campestrefield clover, hop clover
Distribution: Occurring chiefly west of the Cascades in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Wastelots, roadsides, fields, meadows, and other disturbed areas.
Origin: Introduced from Europe
Flowers: May-August
Growth Duration: Annual, Biennial
Trifolium cernuumnodding clover
Distribution: Known from the Olympic Peninsula in Washington; Washington to California.
Habitat: Roadsides, lawns, fields, and other disturbed open areas at low elevations.
Origin: Introduced
Flowers: April-May
Growth Duration: Annual
Trifolium ciliolatumfoothill clover, tree clover
Distribution: Occurring east of the Cascades crest in south-central Washington; south-central Washington to California.
Habitat: Wet meadows to rather dry, sandy soil.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Trifolium cyathiferumbowl clover, cup clover
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to western Montana and Nevada.
Habitat: Wet meadows and seeps to fairly dry, sandy soil, at moderate elevations.
Origin: Native
Flowers: May-July
Growth Duration: Annual
Trifolium depauperatumpoverty clover
Distribution: Occurring west of the Cascades crest in northwestern Washington; also in Gulf Islands and Vancouver Islands in British Columbia, otherwise southwestern Oregon to southern California.
Habitat: Coastal bluffs and vernally moist areas.
Origin: Native
Flowers: April-June
Growth Duration: Annual
var. depauperatum – poverty clover
Trifolium dichotomumbranched clover
Distribution: Occurring west of the Cascades crest in the San Juan Islands in Washington; southern Vancouver Island, Gulf Islands, and San Juan Islands, otherwise Willamette Valley, Oregon to California.
Habitat: Open forest, sandy embankments, and grassy balds on islands.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Trifolium douglasiiDouglas's clover
Distribution: Occurring east of the Cascades crest in eastern and southeastern Washington; eastern Washington to east-central Oregon, east to eastern Idaho.
Habitat: Moist to wet areas in including open meadows, forested wetlands, and streambanks.
Origin: Native
Flowers: June-July
Growth Duration: Perennial
Trifolium dubiumleast hop clover, suckling clover
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east across much of North America to the Atlantic Coast.
Habitat: Forest openings, roadsides, fields, lawns, wastelots, and other disturbed sites.
Origin: Introduced from Europe
Flowers: April-September
Growth Duration: Annual
Trifolium eriocephalumwoolly-head clover
Distribution: Occurring on both sides of the Cascades crest in southern Washington; southern Washington to California, east to Montana, Utah, and Nevada.
Habitat: Meadows and forest openings at middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. arcuatum – woolly-head clover
var. eriocephalum – woolly-head cloover
Trifolium fragiferumstrawberry clover
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; southern British Columbia to California, east to the Great Plains, also in eastern North America.
Habitat: Roadsides, fields, lawns, wastelots and other disturbed places.
Origin: Introduced from Europe
Flowers: April-July
Growth Duration: Perennial
Trifolium glomeratumclustered clover
Distribution: Occurring west of the Cascades crest in the Puget Trough lowlands; southwestern British Columbia to California.
Habitat: Roadsides, lawns, and other disturbed sites often with dry, gravelly, compacted soil.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium gracilentumslender clover
Distribution: Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington; Washington to California, where native, and east to Arizona.
Habitat: Grassy slopes, fields, and roadsides.
Origin: Introduced from California
Flowers: April-June
Growth Duration: Annual
Trifolium hirtumrose clover
Distribution: Occurring in the Columbia River Gorge in Washington; Washington to California, also in the southeastern U.S.
Habitat: Roadsides, fields, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium hybridumalsike clover
Distribution: Occurring on both sides of the Cascades crest throughout much of Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Roadsides, fields, meadows, wastelots, and other disturbed open areas.
Origin: Introduced from Europe
Flowers: April-September
Growth Duration: Perennial
Trifolium incarnatumcrimson clover
Distribution: Occurring west of the Cascades crest in the Puget Trough lowlands; British Columbia to California, east across much of North America to the Atlantic Coast.
Habitat: Roadsides, fields, meadows, wastelots, and other disturbed open areas.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium latifoliumtwin clover
Distribution: Occurring east of the Cascades crest in far eastern and southeastern Washington; eastern Washington to northeastern Oregon, east to western Montana.
Habitat: Moist meadows to rocky ridges.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Trifolium longipeslong-stalked clover
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Meadows and valleys, lower mountains to subalpine slopes.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. longipes – long-stalked clover
var. multiovulatum – long-stalked clover
var. multipedunculatum – long-stalked clover
Trifolium macrocephalumbig-head clover, large-head clover
Distribution: Occurring east of the Cascades crest in Washington; Washington, south through eastern Oregon, east to Idaho and Nevada.
Habitat: Shrub-steppe, sagebrush desert and ponderosa pine woodlands.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Trifolium microcephalumsmall-head clover
Distribution: Distributed widely throughout Washington; British Columbia to Baja California, east to the Rocky Mountains.
Habitat: Moist meadows, sandy riverbanks and drier hillsides, coastal to mid-elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Trifolium microdonthimble clover, Valparaiso clover
Distribution: Occurring chiefly west of the Cascades crest and in the Columbia River Gorge in Washington; British Columbia to California; also in South America.
Habitat: In meadows or on rocky or sandy soil at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Trifolium oliganthumfew-flowered clover
Distribution: Occurring west of the Cascades crest in Washington; southwestern British Columbia to California.
Habitat: Balds, grasslands, and prairies at low elevations, often where dry and rocky.
Origin: Native
Flowers: April-June
Growth Duration: Annual
Trifolium plumosumplumed clover
Distribution: Occurring in the southeastern region in Washington; southeastern Washington to northeastern Oregon, east to adjacent Idaho.
Habitat: Dry hillsides, meadowlands, and forest openings.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
var. amplifolium – plumed clover
var. plumosum – plumed clover
Trifolium pratensered clover
Distribution: Widely distributed on both sides of the Cascades crest in Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Escaped from cultivation; found along mountain trails where horses have been used
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Biennial, Perennial
Trifolium repensDutch clover, white clover
Distribution: Widely distributed throughout Washington; Alaska to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields, lawns, meadows, wastelots, trailsides, and other disturbed open areas from low elevations to the subalpine.
Origin: Introduced from Europe
Flowers: April-September
Growth Duration: Perennial
Trifolium resupinatumreversed clover
Distribution: Occurring east of the Cascades crest in eastern Washington; eastern Washington to California, also in eastern North America.
Habitat: Roadsides, wastelots, and disturbed open areas.
Origin: Introduced from Eurasia
Flowers: May-June
Growth Duration: Annual
Trifolium retusumteasel clover
Distribution: Occurring west of the Cascades crest in the Puget Trough region in Washington; also occurring in southern Oregon and northern California.
Habitat: Roadsides, fields, meadows, lawns, wastelots, and other disturbed open areas at low elevations.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium striatumknotted clover
Distribution: Occurring in lowlands west of the Cascades crest in Washington; Washington to California, also in eastern North America.
Habitat: Disturbed, open areas at low elevation.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium subterraneumburrowing clover, subterranean clover, subterranean trefoil
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California; also in the southeastern U.S.
Habitat: Pastures, prairies, roadsides, lawns, fields, and other open disturbed areas at low elevations.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual
Trifolium suffocatumsuffocated clover
Distribution: Occurring west of the Cascades crest in Washington; Washington and in California
Habitat: Roadsides, fields, wastelots, lawns, and other disturbed areas.
Origin: Introduced from Europe
Flowers: April-June
Trifolium thompsoniiThompson's clover
Distribution: Endemic to Chelan and Douglas counties in Washington.
Habitat: Common on dry, grassy hillsides just below the ponderosa pine woodlands.
Origin: Native
Flowers: May-June
Growth Duration: Perennial
Trifolium variegatumwhite-tip clover
Distribution: Widely distributed throughout much of Washington; Alaska south to California, east to Montana, Wyoming, Utah, and Arizona.
Habitat: Dry, sandy soil to moist meadows.
Origin: Native
Flowers: April-July
Growth Duration: Annual
Trifolium vesiculosumarrow-leaf clover
Distribution: Occurring in a few locations west of the Cascades crest in lowland western Washington; Washington to California; also in the south-central and southeastern U.S.
Habitat: Roadsides, fields, wastelots, and other disturbed open areas.
Origin: Introduced from Europe
Flowers: May-July
Growth Duration: Annual
Trifolium willdenoviisand clover, tomcat clover
Distribution: Occurring west of the Cascades crest and east along the Columbia River in Washington; British Columbia to California.
Habitat: Grassy hillsides, balds, prairies, and meadows at low to moderate elevations.
Origin: Native
Flowers: April-July
Growth Duration: Annual
Trifolium wormskioldiicow clover, salt marsh clover
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to Idaho, Colorado, and New Mexico.
Habitat: Costal dunes to moist meadows and stream banks at low to moderate elevations in the mountains.
Origin: Native
Flowers: May-September
Growth Duration: Annual, Perennial
Triglochin concinnagraceful arrow-grass
Distribution: Occurring west of the Cacades crest along the coast in Washington; southwestern British Columbia to California, east to the Rocky Mountains and northern Great Plains.
Habitat: Dry meadows and marshes, always where brackish or saline to alkaline.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
var. concinna – graceful arrow-grass
Triglochin maritimaseaside arrow-grass
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, further eastward across the northern U.S. and southern Canada to the Atlantic Coast.
Habitat: Marshy to moist, gravelly areas, mostly were saline or alkaline.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Triglochin palustrismarsh arrow-grass
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, Great Plains, Great Lakes region, and northeastern North America; circumboreal and in South America.
Habitat: Coastal bogs to inland meadows, mudflats, and gravelly stream margins, often where brackish or alkaline.
Origin: Native
Flowers: June-August
Growth Duration: Perennial
Triglochin scilloidesawl-leaf arrow-grass, flowering quillwort
Distribution: Occurring chiefly west of the Cascades crest along the coastal counties in Washington; British Columbia to Baja California, Mexico, east to the Rocky Mountains and northern Great Plains; also in South America.
Habitat: Generally in shallow water, but often stranded in mud at edge of receding ponds, coastal tideflats to interior valleys.
Origin: Native
Flowers: July-September
Growth Duration: Perennial
Triglochin striatastriate arrow-grass
Distribution: Occurring west of the Cascades crest along the coast in Washington; Washington to California; also in the southeastern U.S.
Habitat: Coastal alkaline marshes.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Trillium albidumgiant trillium, sessile trillium
Distribution: Occurring west of the Cascades crest in Washington; Washington to California.
Habitat: Moist forests, oak-ash woodlands, thickets, and fields at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
ssp. parviflorum – small-flowered trillium
Trillium crassifoliumthick-leaved trillium, thick-leaved wake-robin
Distribution: Occurring east of the Cascades crest in the Wenatchee Mountains and in the Blue Mountains; central Washington, and in Idaho eastern Oregon.
Habitat: Open woods vegetated rock outcrops.
Origin: Native
Flowers: March-June
Growth Duration: Perennial
Trillium ovatum
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California.
Habitat: Open to dense moist forests at low to mid-elevations, often where boggy in the spring.
Origin: Native
Flowers: March-June
Growth Duration: Perennial
Trillium petiolatumpurple trillium, purple wake-robin
Distribution: Occurring east of the Cascades crest in Washington; Washington to northeastern Oregon, east to Idaho.
Habitat: Stream banks, moist meadows, forest edge, and thickets at low to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
Trillium stenosepalumwestern white trillium, western wake-robin
Distribution: Occurring east of the Cascades crest in eastern Washington; south-central British Columbia and southwestern Alberta to central Idaho and western Montana, disjunct in Wyoming and Colorado.
Habitat: Moist woods.
Origin: Native
Flowers: April-July
Growth Duration: Perennial
Triodanis perfoliataclasping-leaf Venus'-looking-glass
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Various habitats, from the valleys and plains to moderate elevations in the moutains.
Origin: Native
Flowers: May-August
Growth Duration: Annual
Triphysaria pusilladwarf owl-clover
Distribution: Occurring west of the Cascades crest and east in the Columbia River Gorge in Washington; southwestern British Columbia to California.
Habitat: Vernally moist, open ground at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual
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
Distribution: Occurring west of the Cascades crest in Washington in the Lower Columbia River area; southwestern Washington to adjacent Oregon; native from southern Rocky Mountains and Great Plains to the Atlantic coast.
Habitat: Sandy riverbanks.
Origin: Introduced from central and eastern North America
Flowers: June-August
Growth Duration: Perennial
var. purpurea – purple sandgrass
Tripleurospermum inodorumfalse chamomile, false mayweed, scentless mayweed
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Noxious weed in fields and waste ground in eastern Washington.
Origin: Introduced from Europe
Flowers: June-September
Growth Duration: Annual
Trisetum canescenstall false oat
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains.
Habitat: Moist to dry meadows and forest, stream banks, springs, and rocky slopes.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Trisetum cernuumnodding trisetum
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to Alberta, Idaho, and Montana.
Habitat: Moist to dry meadows and forest, stream banks, springs, and rocky slopes.
Origin: Native
Flowers: May-July
Growth Duration: Perennial
Trisetum spicatumnarrow false oat, spike trisetum
Distribution: Occurring 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
Triteleia grandiflorablue-lily, blue umber lily, large-flowered tritelia
Distribution: Occurring chiefly east of the Cascades crest in Washington, but also occurring in the north Puget Sound area; British Columbia to California, east to Montana, Idaho, Wyoming and Utah.
Habitat: Prairies, grasslands, balds and forest openings, often where seasonally dry, from the coast to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial
var. grandiflora – blue-lily, Douglas' brodiaea, blue umber lily, large-flowered tritelia
var. howellii – Howell's large-flowered triteleia, Howell's triteleia
Triteleia hyacinthinawhite brodiaea, fool's-onion, wild hyacinth
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho.
Habitat: Sagebrush deserts and grassy, often rocky areas from low to middle elevations in the mountains.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Triticum aestivumbread wheat
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: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: April-June
Growth Duration: Annual
Trollius albifloruswestern globeflower
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Washington, east to the Rocky Mountains.
Habitat: Subalpine and alpine wet meadows and slopes, blooming as the snow recedes.
Origin: Native
Flowers: May-August
Growth Duration: Perennial
Tsuga heterophyllawestern hemlock
Distribution: Occurring chiefly west of the Cascades crest and in the northeast counties in Washington; Alaska to California, also in southeastern British Columbia, northern Idaho and western Montana.
Habitat: Moist, deep forests from sea level to middle elevations in the mountains
Origin: Native
Cones: May-June
Growth Duration: Perennial
Tsuga ×jeffreyi
Origin: Native
Growth Duration: Perennial
Tsuga mertensianamountain hemlock
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Montana.
Habitat: Middle to high elevations in the mountains
Origin: Native
Cones: June-July (cones)
Growth Duration: Perennial
Turritis glabratower mustard
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to northern California, east to the Rocky Mountains, northern Great Plains, and eastern North America.
Habitat: Seasonally moist, sometimes rocky, soil in open woods, clearings, and grassy balds.
Origin: Native
Flowers: May-July
Growth Duration: Annual, Biennial, Perennial
Tussilago farfaracoltsfoot
Distribution: Occurring west of the Cascades crest in lowland western Washington; British Columbia to Washington; also from the Great Lakes region east to the Atlantic Coast.
Habitat: Roadsides, fields, lawns, wastelots, and disturbed forest understory ta low elevations.
Origin: Introduced from Eurasia
Flowers: March-May
Growth Duration: Perennial
Typha angustifolianarrow-leaf cat-tail
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to Idaho; native from the Great Plains to the Atlantic Coast; also in Eurasia.
Habitat: Shallow, quiet to slow-moving water.
Origin: Introduced from Europe and/or eastern North America
Flowers: May-August
Growth Duration: Perennial
Typha domingensissouthern cat-tail
Distribution: Occurring on both sides of the Cascades crest in Washington; also from California east across the southern half of the U.S. to the Atlantic Coast.
Habitat: Shallow, quiet to slow-moving water.
Origin: Introduced from central and South America
Flowers: May-August
Growth Duration: Perennial
Typha ×glaucasmooth cat-tail
Distribution: Occurring on both sides of the Cascades crest in Washington; also occurring in scattered locations in Montana and elsewhere in the U.S.
Habitat: Shallow, quiet to slow-moving water.
Origin: Introduced
Flowers: May-September
Growth Duration: Perennial
Typha latifoliabroad-leaf cat-tail, common cattail
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across North Americca to the Atlantic Coast.
Habitat: Marshes, ponds and shallow slow-flowing water, sea level to mid-elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial