Polygonum shastense
Encyclopedia
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 Oregon
, Nevada
, and California
, where it grows in rocky and gravelly mountainous habitat.
producing branching tough, gnarled brown stems reaching a maximum length of 40 centimeters, growing prostrate along the ground or somewhat upright. The leaves lining the slender stems are uniform in size and distribution, not clustered or reduced in size near stem tips. They are lance-shaped with two raised ridges on the upper surface, each leaf measuring less than 2 centimeters long. Leaves have stipule
s which are widened into membranous ochrea
wrapped around the leaf bases. Flowers occur in clusters in upper leaf axils. Each is just under a centimeter wide and has five green-veined, rounded white or pink lobes.
Polygonaceae
Polygonaceae is a family of flowering plants known informally as the "knotweed family" or "smartweed family"— "buckwheat family" in the United States. The name is based on the genus Polygonum and was first used by Antoine Laurent de Jussieu in 1789 in his book, Genera Plantarum. The name refers...
known by the common name Shasta knotweed. It is native to sections of Oregon
Oregon
Oregon is a state in the Pacific Northwest region of the United States. It is located on the Pacific coast, with Washington to the north, California to the south, Nevada on the southeast and Idaho to the east. The Columbia and Snake rivers delineate much of Oregon's northern and eastern...
, Nevada
Nevada
Nevada is a state in the western, mountain west, and southwestern regions of the United States. With an area of and a population of about 2.7 million, it is the 7th-largest and 35th-most populous state. Over two-thirds of Nevada's people live in the Las Vegas metropolitan area, which contains its...
, and California
California
California is a state located on the West Coast of the United States. It is by far the most populous U.S. state, and the third-largest by land area...
, where it grows in rocky and gravelly mountainous habitat.
Description
Polygonum shastense is a small shrubShrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...
producing branching tough, gnarled brown stems reaching a maximum length of 40 centimeters, growing prostrate along the ground or somewhat upright. The leaves lining the slender stems are uniform in size and distribution, not clustered or reduced in size near stem tips. They are lance-shaped with two raised ridges on the upper surface, each leaf measuring less than 2 centimeters long. Leaves have stipule
Stipule
In botany, stipule is a term coined by Linnaeus which refers to outgrowths borne on either side of the base of a leafstalk...
s which are widened into membranous ochrea
Ochrea
Ochrea, commonly spelled ocrea, is a structure formed of stipules fused into a sheath surrounding the stem. It is a diagnostic character in the Polygonaceae.In palms it denotes an extension of the leaf sheath beyond the petiole insertion....
wrapped around the leaf bases. Flowers occur in clusters in upper leaf axils. Each is just under a centimeter wide and has five green-veined, rounded white or pink lobes.