''Polygonum bolanderi'' is an uncommon California species of flowering plant in the buckwheat family known by the common name Bolander's knotweed.

Distribution

''Polygonum bolanderi'' is

endemic Endemism is the state of a species being found in a single defined geographic location, such as an island, state, nation, country or other defined zone; organisms that are indigenous to a place are not endemic to it if they are also found elsew ...

to northern

California California is a U.S. state, state in the Western United States, located along the West Coast of the United States, Pacific Coast. With nearly 39.2million residents across a total area of approximately , it is the List of states and territori ...

, where it is known from the northern

Coast Ranges The Pacific Coast Ranges (officially gazetted as the Pacific Mountain System in the United States) are the series of mountain ranges that stretch along the West Coast of North America from Alaska south to Northern and Central Mexico. Although the ...

, the southern Cascades, and the northern

Sierra Nevada The Sierra Nevada () is a mountain range in the Western United States, between the Central Valley of California and the Great Basin. The vast majority of the range lies in the state of California, although the Carson Range spur lies primarily ...

(from Humboldt County and Shasta, south as far as

Sonoma county Sonoma County () is a county (United States), county located in the U.S. state of California. As of the 2020 United States Census, its population was 488,863. Its county seat and largest city is Santa Rosa, California, Santa Rosa. It is to the n ...

and

Tuolumne County Tuolumne County (), officially the County of Tuolumne, is a county located in the U.S. state of California. As of the 2020 census, the population was 55,620. The county seat and only incorporated city is Sonora. Tuolumne County comprises the ...

). It can be found in open, rocky habitats.

Description

''Polygonum bolanderi'' is a small

shrub A shrub (often also called a bush) is a small-to-medium-sized perennial woody plant. Unlike herbaceous plants, shrubs have persistent woody stems above the ground. Shrubs can be either deciduous or evergreen. They are distinguished from trees ...

producing numerous very thin twiglike branches up to about half a meter (20 inches) long from a tough, tangled base. The slender branches are lined with small, narrow, pointed leaves which are alternately arranged and mostly found clustered toward the tips of the twigs. The leaves have narrow, fringed

stipule In botany, a stipule is an outgrowth typically borne on both sides (sometimes on just one side) of the base of a leafstalk (the petiole). Stipules are considered part of the anatomy of the leaf of a typical flowering plant, although in many speci ...

s with sharp points. Flowers occur in upper leaf axils during summer and fall. They are whitish or pink with dark midveins on each corolla lobe.Flora of North America, ''Polygonum bolanderi'' W. H. Brewer, 1872. Bolander's knotweed
/ref>

References

External links

Jepson Manual Treatment - ''Polygonum bolanderi''''Polygonum bolanderi'' - Calphotos Photo gallery, University of California
bolanderi Endemic flora of California Flora of the Cascade Range Flora of the Sierra Nevada (United States) Natural history of the California Coast Ranges Plants described in 1872 Flora without expected TNC conservation status {{Polygonaceae-stub