netleaf hackberry (Celtis reticulata)
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east through Southern Rockies to Kansas, Oklahoma and Texas.
Habitat: Open slopes and rocky bluffs.
Origin: Native
Flowers: April-May
Growth Duration: Perennial

early silver hairgrass (Aira praecox)
Distribution: Occurring chiefly west of the Cascades crest in Washington; British Columbia to California; also 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 from Europe
Flowers: April-September
Growth Duration: Annual

mountain hairgrass (Vahlodea atropurpurea)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains, east across Canada to the Atlantic Coast.
Habitat: Mountain meadows, streambanks, and lake margins to alpine ridges.
Origin: Native
Flowers: June-August
Growth Duration: Perennial

slender hairgrass (Deschampsia elongata)
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

puzzling halimolobos (Sandbergia perplexa)
Distribution: Occurring east of the Cascades crest in Washington, where known only from Douglas County; disjunct in central Washington, otherwise to western Idaho to southwestern Montana.
Habitat: Sagebrush desert, typically on lithosol.
Origin: Native
Flowers: April-June
Growth Duration: Perennial

common hardgrass (Sclerochloa dura)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual

Alaska harebell (Campanula lasiocarpa)
Distribution: Occurring west of the Cascades crest in central Washington; Alaska to Washington, east to Northwest Territories and Alberta.
Habitat: Subalpine and alpine rock crevices and heathlands.
Origin: Native
Flowers: July-August
Growth Duration: Perennial

Parry's harebell (Campanula parryi)
Distribution: Occurring in the Cascades Range and Olympic Mountains in Washington, where disjunct; central Idaho and adjacent Montana south in Rocky Mountains to Arizona and New Mexico.
Habitat: In subalpine and alpine areas.
Origin: Native
Flowers: July-August
Growth Duration: Perennial

rover harebell (Campanula rapunculoides)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to Oregon, east across much of North America to the Atlantic Coast.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial

autumn hawkbit (Leontodon autumnalis)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to Oregon, east to Idaho and Montana; also in eastern North America.
Habitat: Roadsides, pastures, open fields and other disturbed areas primarily in the lowlands, but also found along roads at alpine elevations in the mountains (e.g., Mt. Baker area).
Origin: Introduced from Eurasia
Flowers: July-September
Growth Duration: Perennial

annual hawksbeard (Crepis tectorum)
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east across the northern regions of the U.S. and Canada to the Atlantic Coast.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed, open areas.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Annual

bearded hawksbeard (Crepis barbigera)
Distribution: Occurring east of the Cascades crest in Washington; Washington to Oregon, east to Idaho.
Habitat: Sagebrush deserts to ponderosa pine forest openings at middle elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

dandelion hawksbeard (Crepis runcinata)
Distribution: Occurring east of the Cascades crest in Washington; southeastern British Columbia to California, east to the Great Plains.
Habitat: Moist to dry meadows, marshes, seeps, shores, riverbanks, often where alkaline, from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

gray hawksbeard (Crepis intermedia)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Open forest, grassland, meadows, rocky or sandy slopes, and ridges from low to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

limestone hawksbeard (Crepis intermedia)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains.
Habitat: Open forest, grassland, meadows, rocky or sandy slopes, and ridges from low to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

low hawksbeard (Askellia pygmaea)
Distribution: Occurring in the Olympic and Cascades mountains in Washington; Alaska to California, east to Nunavut and Colorado, also in northeastern Canada; Asia.
Habitat: Talus, scree, moraines, sandy or gravelly slopes, subalpine to alpine.
Origin: Native
Flowers: July-September
Growth Duration: Perennial

meadow hawksbeard (Crepis runcinata)
Distribution: Occurring east of the Cascades crest in Washington; southeastern British Columbia to California, east to the Great Plains.
Habitat: Moist to dry meadows, marshes, seeps, shores, riverbanks, often where alkaline, from the lowlands to middle elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

narrow leaf hawksbeard (Crepis tectorum)
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Alaska to California, east across the northern regions of the U.S. and Canada to the Atlantic Coast.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed, open areas.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Annual

rough hawksbeard (Crepis setosa)
Distribution: Occurring west of the Cascades crest in southwestern Washington; southwestern British Columbia to California, also in Montana and eastern U.S.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed open areas at low elevations.
Origin: Introduced
Flowers: June-August
Growth Duration: Annual

smooth hawksbeard (Crepis capillaris)
Distribution: Occurring chiefly west of the Cascades crest and east in the Columbia River Gorge in Washington; Alaska to California, east across most of North America to the Atlantic Coast.
Habitat: Roadsides, fields, ditches, wastelots, and other disturbed, open areas at low elevation.
Origin: Introduced from Europe
Flowers: May-November
Growth Duration: Annual, Biennial

Turkish hawksbeard (Crepis nicaeensis)
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; southwestern British Columbia to southwestern Oregon, also in western Montana, the Great Lakes region, and northeastern North America.
Habitat: Roadsides, fields, pastures, forest openings, and other disturbed areas, often where at least seasonally moist.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Annual

alpine hawkweed (Hieracium triste)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains of Canada and the U.S.
Habitat: Meadows and other open places in the mountains, usually at high elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial

common hawkweed (Hieracium lachenalii)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to northern Oregon; also in eastern North America.
Habitat: Open forest, fields, shores, wastelots, and other disturbed areas generally at low to middle elevations.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial

European hawkweed (Hieracium lachenalii)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to northern Oregon; also in eastern North America.
Habitat: Open forest, fields, shores, wastelots, and other disturbed areas generally at low to middle elevations.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial

forked hawkweed (Hieracium ×stoloniflorum)
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; no other reports from North America.
Habitat: Lawns, roadsides, ditches, and other disturbed areas, where escaping from cultivation.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial

long-bearded hawkweed (Hieracium longiberbe)
Distribution: Occurring in the Columbia River Gorge in Washington; south-central Washington to adjacent north-central Oregon; endemic to the Columbia River Gorge.
Habitat: Dry rocky slopes and ledges.
Origin: Native
Flowers: June-July
Growth Duration: Perennial

mottled hawkweed (Hieracium maculatum)
Distribution: Occurring west of the Cascades crest in lowland western Washington; southwestern British Columbia to western Washington.
Habitat: Lawns, railroads, wastelots, and other disturbed areas at low elevations.
Origin: Introduced from Europe
Flowers: June-August

narrowleaf hawkweed (Hieracium umbellatum)
Distribution: Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; Alaska to northwestern Oregon, east across the northern half of North America to the Atlantic Coast; circumboreal.
Habitat: Moist places in thickets and open woods.
Origin: Native
Flowers: July-September
Growth Duration: Perennial

savoy hawkweed (Hieracium sabaudum)
Distribution: Occurring west of the Cascades crest in Washington; southern British Columbia to Washington; also in eastern North America.
Habitat: Roadsides, sandy fields, and other disturbed areas.
Origin: Introduced from Europe
Flowers: June-August
Growth Duration: Perennial

slender hawkweed (Hieracium triste)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to the Rocky Mountains of Canada and the U.S.
Habitat: Meadows and other open places in the mountains, usually at high elevations.
Origin: Native
Flowers: June-August
Growth Duration: Perennial

umbellate hawkweed (Hieracium umbellatum)
Distribution: Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; Alaska to northwestern Oregon, east across the northern half of North America to the Atlantic Coast; circumboreal.
Habitat: Moist places in thickets and open woods.
Origin: Native
Flowers: July-September
Growth Duration: Perennial

whip hawkweed (Hieracium flagellare)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to Washington, east to Idaho; also in eastern North America.
Habitat: Roadsides, dry meadows, railroads, and other disturbed, open areas at low elevations.
Origin: Introduced from Europe
Flowers: May-September
Growth Duration: Perennial

white-flowered hawkweed (Hieracium albiflorum)
Distribution: Widely distributed in forested areas on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and eastern Canada.
Habitat: Open woods from low to middle elevations.
Origin: Native
Flowers: June-September
Growth Duration: Perennial

black hawthorn (Crataegus douglasii)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Saskatchewan, Idaho and Montana, also in the Great Lakes region.
Habitat: Thickets, open forests, forest edges, and riparian zones, from lowlands to middle elevations.
Origin: Native
Flowers: May-June
Growth Duration: Perennial

common hawthorn (Crataegus monogyna)
Distribution: Occurring chiefly west of the Cascades crest in Washington; southern British Columbia to California, east to Montana, also in the Great Lakes region and eastern North America.
Habitat: Roadsides, fields, pastures, meadows, thickets, and forest edge and understory at low elevations, often associated with disturbance. Seeds readily dispersed by birds.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Perennial

fireberry hawthorn (Crataegus chrysocarpa)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to Oregon, east across the northern U.S. and Canada to the Atlantic Coast.
Habitat: Thickets, dry slopes, shrub-steppe, riparian zones, forest openings.
Origin: Native
Flowers: May-June
Growth Duration: Perennial

large-thorned hawthorn (Crataegus macracantha)
Distribution: Occurring east of the Cascades crest in Washington; southern British Columbia to northeastern Oregon, east to the Rocky Mountains, and further east across the U.S. and Canada to the Atlantic Coast.
Habitat: Thickets, riparian zones, and pastures.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

O'Kennon's hawthorn (Crataegus okennonii)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to Washington, east to Idaho and Montana.
Habitat: Thickets, riparian zones, and grasslands.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

one-seed hawthorn (Crataegus monogyna)
Distribution: Occurring chiefly west of the Cascades crest in Washington; southern British Columbia to California, east to Montana, also in the Great Lakes region and eastern North America.
Habitat: Roadsides, fields, pastures, meadows, thickets, and forest edge and understory at low elevations, often associated with disturbance. Seeds readily dispersed by birds.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Perennial

Phipps's hawthorn (Crataegus phippsii)
Distribution: Occurring east of the Cascades crest in north-central Washington; southern British Columbia to northern Washington, also in Montana but not known from Idaho.
Habitat: Floodplains, open forests, and thickets.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

Suksdorf's hawthorn (Crataegus gaylussacia)
Distribution: Occurring on both sides of the Cascades crest in Washington; disjunct in southeast Alaska, otherwise southern British Columbia to California, east to Montana.
Habitat: Thickets, grasslands, riparian zones, shores, and meadows, from lowl to middle elevations in the mountains.
Origin: Native
Flowers: April-June
Growth Duration: Perennial

woodland hawthorn (Crataegus laevigata)
Distribution: Known only from the San Juan Islands in Washington.
Origin: Introduced from northern Europe
Growth Duration: Perennial

European hazelnut (Corylus avellana)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to Oregon, also known from western Idaho.
Habitat: Abandoned plantings, roadsides, waste sites, forest edge.
Origin: Introduced from Europe
Flowers: January-April
Growth Duration: Perennial

common heath-grass (Danthonia decumbens)
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

alpine heather (Harrimanella stelleriana)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to Washington.
Habitat: Rocky slopes and seeps, alpine to subalpine
Origin: Native
Flowers: June-August
Growth Duration: Perennial

American hedge-hyssop (Gratiola neglecta)
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout most of North America.
Habitat: In shallow water and on muddy shores, and in other wet places in the valleys and plains.
Origin: Native
Flowers: June-August
Growth Duration: Annual

clammy hedge-hyssop (Gratiola neglecta)
Distribution: Occurring on both sides of the Cascades crest in Washington; widely distributed throughout most of North America.
Habitat: In shallow water and on muddy shores, and in other wet places in the valleys and plains.
Origin: Native
Flowers: June-August
Growth Duration: Annual

field hedge-nettle (Stachys arvensis)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California; also along the Gulf Coast and in the northeastern U.S.
Habitat: Weed in disturbed areas, typically where moist.
Origin: Introduced from Europe
Flowers: April-June
Growth Duration: Annual

rigid hedge-nettle (Stachys rigida)
Distribution: Occurring west of the Cascades crest in Washington; southwestern Washington to California.
Habitat: Stream banks and moist bottom lands, mostly at low elevations.
Origin: Native
Flowers: July-August
Growth Duration: Perennial

California hedge-parsley (Yabea microcarpa)
Distribution: Occurring on both sides of the Cascades crest in Washington and in the Columbia River Gorge. British Columbia to Baja California, east to Idaho, Utah, and New Mexico.
Habitat: Along streams, open woodlands, and vernally moist slopes at low elevations.
Origin: Native
Flowers: April-June
Growth Duration: Annual

field hedge-parsley (Torilis arvensis)
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

upright hedge-parsley (Torilis japonica)
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

salt heliotrope (Heliotropium curassavicum)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Saline places at low elevations, often in the beds of dried ponds.
Origin: Native
Flowers: June-September
Growth Duration: Annual, Perennial

siskiyou wild hellebore (Veratrum insolitum)
Distribution: Occurring in the Columbia River Gorge in Washington; south-central Washington to northern California.
Habitat: Open prairies to thickets, and forested or open rocky slopes.
Origin: Native
Flowers: July - September
Growth Duration: Perennial

broad-leaved helleborine (Epipactis helleborine)
Distribution: Occurring west of the Cascades crest in lowland areas in Washington; British Columbia to California, in scattered locations across North America to the Atlantic Coast, where more common.
Habitat: Moist to dry forest edge and understory, often where disturbed.
Origin: Introduced from Eurasia
Flowers: June-October
Growth Duration: Perennial

giant helleborine (Epipactis gigantea)
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Baja California, east to the Rocky Mountains and in scattered locations in the Great Plains.
Habitat: Stream banks, lake margins, around springs and seeps, especially in thermal waters in otherwise desert regions.
Origin: Native
Flowers: April-July
Growth Duration: Perennial

policeman's helmet (Impatiens glandulifera)
Distribution: Occurring west of the Cascades crest in Washington; Alaska to California, east to Idaho; also in eastern North America.
Habitat: Escaped from cultivation in disturbed forest edge at low elevations.
Origin: Introduced from Asia
Flowers: July-September
Growth Duration: Annual

western hemlock (Tsuga heterophylla)
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

hemp (Cannabis sativa)
Distribution: Occurring in scattered locations on both sides of the Cascades crest, but not likely persisting anywhere; occurring sporadically in other areas of North America.
Habitat: Illegal plantings in forest openings, roadsides, wastelots, and other disturbed areas, where escaping from cultivation.
Origin: Introduced from Asia
Flowers: June-September
Growth Duration: Annual

common hemp nettle (Galeopsis tetrahit)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to Montana, east across Canada and parts of midwestern U.S. to the Atlantic Coast.
Habitat: Disturbed meadows, roadsides, forest edge, and other moist places.
Origin: Introduced from Eurasia
Flowers: July-August
Growth Duration: Annual

spotted hen-nettle (Lamium maculatum)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to Oregon, east to Idaho; also in eastern North America.
Habitat: Fields, roadsides, wastelots, and other disturbed areas.
Origin: Introduced from Eurasia
Flowers: April-August
Growth Duration: Perennial

henbit (Lamium purpureum)
Distribution: Occurring chiefly west of the Cascades crest in Washington; widely distributed throughout much of North America.
Habitat: Roadsides, fields, lawns, parks, wastelots, and other disturbed areas at lower elevations.
Origin: Introduced from Eurasia
Flowers: March-July
Growth Duration: Annual

herb-bennet (Geum urbanum)
Distribution: In scattered locations on both sides of the Cascades crest in Washington; Washington to Oregon, east to Idaho and Utah.
Habitat: Disturbed areas in including, roadsides, wastelots, and fields.
Origin: Introduced from Eurasia
Flowers: May-September
Growth Duration: Perennial

California hesperochiron (Hesperochiron californicus)
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to western Montana, Wyoming, and Utah.
Habitat: Mostly in more or less alkaline meadows and flats, in plains, foothills and valleys.
Origin: Native
Flowers: April-June
Growth Duration: Perennial

high-bush cranberry (Viburnum opulus)
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Oregon, east across Canada and the northern U.S. to the Atlantic Coast.
Habitat: Moist woods at low to moderate elevations.
Origin: Native and introduced from Eurasia
Flowers: May-July
Growth Duration: Perennial

chalapa hoarycress (Lepidium chalepense)
Distribution: Occurring east of the Cascades crest in Washington; British Columbia to California, east to the Great Lakes region.
Habitat: Disturbed areas, especially where dry, often associated with agriculture.
Origin: Introduced from Asia
Flowers: May-June
Growth Duration: Perennial

heart-podded hoarycress (Lepidium draba)
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Roadsides, fields, sagebrush desert, wastelots, and disturbed areas at low to middle elevations.
Origin: Introduced from Eurasia
Flowers: April-August
Growth Duration: Perennial

hogbite (Chondrilla juncea)
Distribution: Occurring chiefly east of the Cascades crest in Washington; British Columbia to California, east to Montana; also occurring in eastern North America.
Habitat: Roadsides, fields, sagebrush desert, wastelots, and other disturbed, open areas at low to middle elevations.
Origin: Introduced from Eurasia
Flowers: July-September
Growth Duration: Perennial

giant hogweed (Heracleum mantegazzianum)
Distribution: Occurring west of the Cascades crest in the Puget Trough lowlands in Washington; southwestern British Columbia to Oregon, also in eastern North America.
Habitat: Disturbed areas often associated with residential development; Class A noxious weed.
Origin: Introduced from Eurasia
Flowers: June-July
Growth Duration: Perennial

Braun's holly-fern (Polystichum braunii)
Distribution: Occurring east of the Cascades crest in Washington, where known only from Pend Oreille County; Alaska to northeastern Washington, east to northern Idaho, also from Great Lakes region to northeastern North America; interruptedly circumboreal.
Habitat: Moist coniferous forest, often where rocky.
Origin: Native
Spores: June-October
Growth Duration: Perennial

holy-clover (Onobrychis viciifolia)
Distribution: Occurring east of the Cascades crest in Washington; Alaska to California, east to the Great Plains, also in eastern North America,
Habitat: Roadsides, fields, wastelots, and other disturbed areas.
Origin: Introduced
Flowers: June-August
Growth Duration: Perennial

honey locust (Gleditsia triacanthos)
Distribution: Occurring east of the Cascades crest and in the Columbia River Gorge in Washington; Washington to California, east across North America where native to the central and eastern regions.
Habitat: On edge of riparian zones, typically in areas with some level of disturbance.
Origin: Introduced from central and eastern North America
Flowers: April-June
Growth Duration: Perennial

Etruscan honeysuckle (Lonicera etrusca)
Distribution: Occasional west of the Cascades crest in Washington; southern British Columbia to Oregon.
Habitat: Thickets, forest edge, wastelots, and other disturbed areas.
Origin: Introduced from the Mediterranean region
Flowers: June-August
Growth Duration: Perennial

Japanese honeysuckle (Lonicera japonica)
Distribution: Occurring in scattered locations on both sides of the Cascades crest in Washington; Washington to California, scattered eastward across the U.S. to the Atlantic Coast.
Habitat: Disturbed areas, woods, and thickets.
Origin: Introduced from Asia
Flowers: May-July
Growth Duration: Perennial

pink honeysuckle (Lonicera hispidula)
Distribution: Occurring west of the Cascades crest in lowland western Washington; British Columbia to California.
Habitat: Forest understory and edge, thickets, balds, and open woodlands at low elevations.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

purple-flower honeysuckle (Lonicera conjugialis)
Distribution: Occurring chiefly east of the Cascades crest in Washington mostly from Mt. Adams south, though a historical record is known from Yakima County; south-central Washington to the Sierra Nevada of California.
Habitat: In woods, meadows and moist open slopes at mid-elevations in the mountains.
Origin: Native
Flowers: June-July
Growth Duration: Perennial

showy fly honeysuckle (Lonicera ×bella)
Distribution: Occurring on both sides of the Cascades crest in Washington; southern British Columbia to Oregon and Idaho, scattered localities in central North America, and more widespread in eastern North America.
Habitat: Forest edge and understory, riparian areas, and disturbed areas at low to moderate elevations.
Origin: Introduced
Flowers: April-June
Growth Duration: Perennial

Utah honeysuckle (Lonicera utahensis)
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to Oregon, east to the Rocky Mountains.
Habitat: From middle to high elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

spiny hopsage (Grayia spinosa)
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to Wyoming and Colorado.
Habitat: Foothills and desert valleys, often in alkaline soil.
Origin: Native
Flowers: April-June
Growth Duration: Perennial

spineless hornwort (Ceratophyllum echinatum)
Distribution: Occurring west of the Cascades crest in Washington; British Columbia to California; also from central North America to the Atlantic Coast.
Habitat: In standing to slow-moving water.
Origin: Native
Flowers: June-August
Growth Duration: Perennial

horse-nettle (Solanum carolinense)
Distribution: Occurring east of the Cascades crest in Washington, where historically, sporadically introduced; Washington to California, east across much of North America to the Atlantic Coast.
Habitat: Fields, roadsides, orchards, wastelots, and other disturbed areas.
Origin: Introduced from the southeastern U.S.
Flowers: June-August
Growth Duration: Perennial

gray horsebrush (Tetradymia canescens)
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

horseradish (Armoracia rusticana)
Distribution: Occurring in scattered locations east of the Cascades crest in Washington; Alaska to California, east across the U.S. and Canada to the Atlantic Coast.
Habitat: Disturbed areas including fields, roadsides and wastelots.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Perennial

Ferriss's horsetail (Equisetum ×ferrissii)
Distribution: Occurring chiefly east of the Cascades crest in Washington; southern British Columbia to California, east across most of North America to the Atlantic Coast.
Habitat: Dry to wet, often disturbed areas, including gravelly roadsides.
Origin: Native
Growth Duration: Perennial

giant horsetail (Equisetum telmateia)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Alaska to California, east to northern Idaho; Europe, northern Africa, and the Middle East.
Habitat: Moist areas in the lowlands.
Origin: Native
Growth Duration: Perennial

Nelson's horsetail (Equisetum ×nelsonii)
Origin: Native

scouring rush horsetail (Equisetum hyemale)
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: Moist to wet areas, lowlands to moderate elevations in the mountains
Origin: Native
Growth Duration: Perennial

shore horsetail (Equisetum ×litorale)
Origin: Native
Growth Duration: Perennial

variegated horsetail (Equisetum variegatum)
Distribution: Occurring chiefly east of the Cascades crest in Washington; Alaska to Oregon, east across southern Canada and the northern third of the United States to the Atlantic Coast; circumboreal.
Habitat: Wet places, from sea level to alpine.
Origin: Native
Growth Duration: Perennial

wood horsetail (Equisetum sylvaticum)
Distribution: Occurring east of the Cascades crest in the northeastern counties in Washington; Alaska to Washington, east across southern Canada and the northern United States to the Atlantic Coast; circumboreal.
Habitat: Shady coniferous forests, bog edges, and swamps
Origin: Native
Growth Duration: Perennial

horseweed (Conyza canadensis)
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California, east to the Atlantic Coast.
Habitat: Roadsides, fields, balds, prairies, ditches, wastelots, and other disturbed, open areas at low elevations.
Origin: Native
Flowers: July-September
Growth Duration: Annual, Biennial

common hound's-tongue (Cynoglossum officinale)
Distribution: Widely distributed east of the Cascades crest in Washington; British Columbia to California, east across North America to the Atlantic Coast.
Habitat: Roadsides, fields, meadows, forest edge, ditches, and other disturbed open areas; noxious weed.
Origin: Introduced from Eurasia
Flowers: May-July
Growth Duration: Biennial

water Howellwort (Howellia aquatilis)
Distribution: Occurring chiefly west of the Cascades crest in Washington; Washington to California, east to Idaho and Montana.
Habitat: In ponds and lakes.
Origin: Native
Flowers: May-July
Growth Duration: Annual

dwarf huckleberry (Vaccinium cespitosum)
Distribution: Widely distributed in the mountainous areas of Washington; Alaska to California, east to the Rocky Mountains, northern Great Plains, Great Lakes region, and northeastern North America.
Habitat: Moist rocky ridges and meadows, mid- to high elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

fool's huckleberry (Rhododendron menziesii)
Distribution: Occurring on both sides of the Cascades crest in Washington; Alaska to California, east to Alberta, Idaho, Montana, and Wyoming.
Habitat: Forest understory and edges from middle elevations to the subalpine.
Origin: Native
Flowers: April-June
Growth Duration: Perennial

tall huckleberry (Vaccinium membranaceum)
Distribution: Widely distributed on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains and Great Lakes region.
Habitat: Common in dry to moist coniferous forests and open areas, moderate to mid-elevations in the mountains.
Origin: Native
Flowers: May-July
Growth Duration: Perennial

small hulsea (Hulsea nana)
Distribution: Occurring on both sides of the Cascades crest in Washington from Mount Rainier south; central Washington to California (not in northeastern Oregon).
Habitat: Generally around volcanic mountains above timberline.
Origin: Native
Flowers: July-September
Growth Duration: Perennial

hutchinsia (Hornungia procumbens)
Distribution: Occurring on both sides of the Cascades crest in Washington; British Columbia to California, east to the Rocky Mountains, central Canada, and Newfoundland.
Habitat: Open areas where seasonally moist.
Origin: Introduced from Europe, North Africa, and Asia
Flowers: March-June
Growth Duration: Annual

wild hyacinth (Triteleia hyacinthina)
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

fineleaf hymenopappus (Hymenopappus filifolius)
Distribution: Occurring east of the Cascades crest in Washington; Washington to California, east to the Great Plains.
Habitat: Dry, often sandy places in the foothills and plains.
Origin: Native
Flowers: May-October
Growth Duration: Perennial