Polygonum arenastrum, commonly known as equal-leaved knotgrass, is a summer annual flowering plant in the knotweed family Polygonaceae. Other common names include common knotweed, prostrate knotweed, mat grass, oval-leaf knotweed, stone grass, wiregrass, and door weed, as well as many others. It is native to Europe and can be found on other continents as an introduced species and a common noxious weed. Knotweed was first seen in North America in 1809 and is now seen across much of the United States and Canada.
Ribes bracteosum, the stink currant, is a species of currant native to western coastal North America from southeastern Alaska to Mendocino County in California.
Persicaria bicornis is a North American species of flowering plant in the buckwheat family (Polygonaceae). The common name is pink smartweed. It is native to the central and southwestern United States from northern Texas west to Arizona, east to Louisiana, and north as far as eastern Wyoming, South Dakota, Iowa, and Illinois.
Lilium columbianum is a lily native to western North America. It is also known as the Columbia lily, Columbia tiger lily, or simply tiger lily.
Toxicoscordion micranthum, the smallflower deathcamas, is a flowering plant in the genus Toxicoscordion. It is native to Oregon and California, primarily in the Coast Ranges from Douglas County to Napa and Sonoma Counties, with isolated populations in Lassen, Plumas, Santa Clara, and San Benito Counties. It is a member of the serpentine soils flora.
Crepis pleurocarpa is a North American species of flowering plant in the family Asteraceae known by the common name nakedstem hawksbeard. It is native to the western United States (Washington, Oregon, northern California and western Nevada.
Rubus nivalis, commonly known as snow raspberry, is a species of flowering plant in the rose family. It is native to northwestern North America: British Columbia, Washington, Idaho, Oregon, and far northern California.
Polygonum californicum is a species of flowering plant in the buckwheat family known by the common name California knotweed. It is native to the west coast of the United States from Washington, Oregon, and northern and central California in the Coast Ranges and Sierra Nevada foothills as far south as Napa and Tulare Counties. It can be found in many types of open habitats.
Polygonum paronychia is a species of flowering plant in the knotweed family known by the common names dune knotweed, black knotweed, and beach knotweed. It is native to the coastline of western North America from British Columbia to California, where it grows in sandy coastal habitat such as beaches, dunes, and scrub.
Polygonum parryi is a species of flowering plant in the knotweed family known by the common names Parry's knotweed and prickly knotweed. It is native to the western United States from Washington to California, where it grows in several types of moist, open habitat in mountainous and coastal areas.
Polygonum shastense is a species of flowering plant in the knotweed family known by the common name Shasta knotweed. It is native to sections of southwestern Oregon, northwestern Nevada, and northern and central California, where it grows in rocky and gravelly mountainous habitat up to 3300 meters (11,000 feet) elevation. It is most common in the Sierra Nevada. The species name refers to its occurrence on Mount Shasta in Shasta County, California.
Ranunculus eschscholtzii is a species of buttercup flower known by the common name Eschscholtz's buttercup.
Polygonum hickmanii is a rare species of flowering plant in the buckwheat family known by the common names Scotts Valley polygonum and Hickman's knotweed. It is endemic to Santa Cruz County, California, where it is known from only two sites in the Scotts Valley. It grows on coastal prairie on mudstone and sandstone substrates, in an area known for its spring wildflowers. The small plant was first noted in 1990 and described as a new species in 1995. The plant is a federally listed endangered species.
Arnica lanceolata is a North American species of flowering plant in the family Asteraceae, known by the common name clasping arnica or lanceleaf arnica. It has a disjunct (discontinuous) distribution in western North America and northeastern North America.
Hieracium parryi is a North American plant species in the tribe Cichorieae within the family Asteraceae. It grows only in the western United States, in southwestern Oregon and northeastern California. It is commonly known as woollyweed.
Koenigia davisiae is a flowering plant in the knotweed family that is known by the common names Davis' knotweed or Newberry knotweed.
Koenigia phytolaccifolia is a species of flowering plant in the knotweed family, known by the common name poke knotweed.
Polygonum cascadense is a species of flowering plant in the buckwheat family known by the common name Cascade knotweed. It has been found only in the State of Oregon in the northwestern United States, in the Cascades and in the Blue Mountains.
Polygonum majus is a North American species of flowering plant in the buckwheat family known by the common name wiry knotweed. It grows in the western United States and western Canada, from British Columbia south as far as the Sierra Nevada of northwestern Inyo County in California, east as far as Montana. Knotweed is a spreading, wiry annual weed that rarely grows higher than a few inches. The leaves are tiny, oblong, bluish-green, and 14 inches broad and 1 inch long. The flowers are tiny and unobtrusive, whitish-green in colour, and appear in the leaf axils in the fall. Knotweed may grow into a dense mat with a diameter of up to three feet, strangling out ideal grass and plants. The branches of this evergreen plant form a strong, wiry mat that reaches barely a few centimeters above the earth. They appear constantly, and gardeners are always fighting them.
Polygonum nuttallii is a North American species of flowering plant in the buckwheat family known by the common name Nuttall's knotweed. It grows in the Pacific Northwest, in British Columbia, Washington, and Oregon.
