Cicuta douglasii, the western water hemlock, is a poisonous plant in the family Apiaceae. It is a perennial plant that grows in wet places such as marshes, stream banks, slough margins, ditches, meadows, and wet pastures. The roots are thick and tuberous, with many smaller tubers on the main tuber, allowing survival in wet conditions. Water hemlock is most abundant in British Columbia, and is indigenous to North America, where it grows primarily from the base of the Rocky Mountains to the Pacific coast, stretching from Alaska all the way to California. Water requirements limit this plant from inhabiting open rangelands.
Allium validum, known by several common names including swamp onion, wild onion, Pacific onion, and Pacific mountain onion, is native to the Cascade Range, to the Sierra Nevada, the Rocky Mountains, and other high-elevation regions in California, Oregon, Washington, Nevada, Idaho and British Columbia.
Olsynium douglasii is a species of flowering plant in the iris family (Iridaceae). Common names include Douglas' olsynium, Douglas' grasswidow, grass-widow, blue-eyed grass, purple-eyed-grass, and satin flower, It is native to western North America, from southern British Columbia south to northern California, and east to northwest Utah. It is the only species in the genus Olsynium in North America, the remaining 11 species being from South America. It was formerly treated in the related genus Sisyrinchium.
Baccharis glutinosa is a species of flowering plant in the daisy family known by the common names saltmarsh baccharis and Douglas' falsewillow.
Arctostaphylos pajaroensis is a species of manzanita known by the common name Pajaro manzanita. It is endemic to California, where it is known mainly from Monterey County.
Carex douglasii is a species of sedge known by the common name Douglas' sedge.
Chaenactis douglasii is a North American species of flowering plant in the daisy family known by the common name Douglas' dustymaiden.
Chorizanthe douglasii is a species of flowering plant in the buckwheat family known by the common names San Benito spineflower and Douglas' spineflower. It is endemic to California, where it grows in the mountains of the Southern California Coast Ranges, from the Santa Lucia Range east to the Gabilan Range.
Cirsium douglasii is a species of thistle known by the common names Douglas' thistle and California swamp thistle.
Diplacus douglasii is a species of monkeyflower known by the common names brownies and purple mouse ears. It is native to the mountains and foothills of California and Oregon, where it is often found on serpentine soils. D. douglasii was first described in a published flora by George Bentham, an English botanist who was considered "the premier systematic botanist of the nineteenth century,." It was later described by Asa Gray, the father of North American botany.
Coreopsis douglasii is a species of flowering plant in the daisy family known by the common name Douglas' tickseed. It is native to California from Santa Clara County to San Diego County, as well as from Mohave County in Arizona.
Limnanthes striata was formerly a species of meadowfoam known by the common name foothill meadowfoam. It has recently been subsumed into the species Limnanthes douglasii in both the Jepson Manual and the Flora of North America. This plant is endemic to California, where it is known from the Sierra Nevada foothills and the southern Klamath Mountains. It grows in wet, grassy habitat, carpeting the edges of vernal pools and ephemeral creeks.
Mentzelia congesta is a species of flowering plants in the family Loasaceae known by the common name united blazingstar.
Microseris douglasii is a species of flowering plant in the aster family known by the common name Douglas' silverpuffs. It is native to western North America from Oregon and California to Baja California. It grows in several types of habitat, including grassland and vernal pools, and on soils containing clay and serpentine.
Minuartia douglasii is a species of flowering plant in the family Caryophyllaceae known by the common name Douglas' stitchwort.
Minuartia pusilla is a species of flowering plant in the family Caryophyllaceae known by the common names annual sandwort and dwarf stitchwort.
Microsteris is a monotypic genus of flowering plants in the phlox family containing the single species Microsteris gracilis, known by the common name slender phlox.
Polygonum douglasii is a species of flowering plant in the knotweed family known by the common name Douglas's knotweed. It is native to much of northern and western North America, where it can be found in many types of habitat, including disturbed areas. It has been found in Canada from British Columbia north to Yukon and east as far as Québec, and in the United States as far south as California, New Mexico, Iowa, and New York.
Silene douglasii is a species of flowering plant in the family Caryophyllaceae known by the common name Douglas's catchfly.
Tanacetum camphoratum is a species of flowering plant in the aster family known by the common names camphor tansy and dune tansy. It is native to the Pacific Coast of North America from British Columbia to California, where it grows in sand dunes and other coastline habitat. This species may be known by the synonym Tanacetum douglasii and is often included in Tanacetum bipinnatum. It is a rhizomatous perennial herb with a thick, low-lying stem up to 25 centimeters long, branching to form a mass of vegetation. It is hairy, glandular, and aromatic, with a camphor scent. The leaves are up to 25 centimeters long and thick but featherlike, divided into many narrow leaflets on each side of the main rachis. Each leaflet in turn has many segments along each side, and the segments are usually divided into several small, knobby segments with folded or curled edges. The inflorescence bears up to 15 flower heads, each about a centimeter wide or slightly wider. Each head contains many yellowish disc florets and many pistillate florets around the edges. The latter may have minute ray florets. The fruit is an achene a few millimeters long which is tipped with a small pappus of toothed scales.
