''Polygonum bidwelliae'' is an uncommon species of flowering plant in the knotweed family known by the common name Bidwell's knotweed. The plant was named for American

suffragist Suffrage, political franchise, or simply franchise, is the right to vote in public, political elections and referendums (although the term is sometimes used for any right to vote). In some languages, and occasionally in English, the right to v ...

Annie Bidwell Annie Kennedy Bidwell (June 30, 1839 – March 9, 1918) was a 19th-century pioneer and founder of society in the Sacramento Valley area of California. She is known for her contributions to social causes, such as women's suffrage, the temperance ...

, who at one time lived in the

Bidwell Mansion Bidwell Mansion, located at 525 Esplanade in Chico, California, was the home of General John Bidwell and Annie Bidwell from late 1868 until 1900, when Gen. Bidwell died. Annie continued to live there until her death in 1918. John Bidwell began ...

Chico, California Chico ( ; Spanish for "little") is the most populous city in Butte County, California. Located in the Sacramento Valley region of Northern California, the city had a population of 101,475 in the 2020 census, reflecting an increase from 86,18 ...

. She is the person who collected the

type specimen In biology, a type is a particular wiktionary:en:specimen, specimen (or in some cases a group of specimens) of an organism to which the scientific name of that organism is formally attached. In other words, a type is an example that serves to a ...

Northern California Northern California (colloquially known as NorCal) is a geographic and cultural region that generally comprises the northern portion of the U.S. state of California. Spanning the state's northernmost 48 counties, its main population centers incl ...

Distribution

''Polygonum bidwelliae'' 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 ...

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

Sacramento Valley , photo =Sacramento Riverfront.jpg , photo_caption= Sacramento , map_image=Map california central valley.jpg , map_caption= The Central Valley of California , location = California, United States , coordinates = , boundaries = Sierra Nevada (ea ...

and adjacent slopes of the southernmost

Cascade Range The Cascade Range or Cascades is a major mountain range of western North America, extending from southern British Columbia through Washington and Oregon to Northern California. It includes both non-volcanic mountains, such as the North Cascades, ...

Butte __NOTOC__ In geomorphology, a butte () is an isolated hill with steep, often vertical sides and a small, relatively flat top; buttes are smaller landforms than mesas, plateaus, and tablelands. The word ''butte'' comes from a French word mea ...

, Shasta, and Tehama Counties. It grows in

chaparral Chaparral ( ) is a shrubland plant community and geographical feature found primarily in the U.S. state of California, in southern Oregon, and in the northern portion of the Baja California Peninsula in Mexico. It is shaped by a Mediterranean c ...

, woodland, and grassland habitat on volcanic soils.

Description

''Polygonum bidwelliae'' is an annual herb producing an erect green, wiry, angled stem reaching 20 centimeters (8 inches) in height. The narrow, pointed leaves are oppositely arranged along the stem, mainly on the upper parts of stem branches. The leaves have relatively large

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 which form

ochrea An ochrea (Latin ''ocrea'', greave or protective legging), also spelled ocrea, is a plant structure formed of stipules fused into a sheath surrounding the stem, and is typically found in the Polygonaceae The Polygonaceae are a family of flower ...

that sheath the stem, sometimes hiding the leaf bases. The sharp-pointed

stipules 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 ...

are membranous and silvery white. Bright pink flowers occur in upper leaf axils.]Japanese Knotweed Agency
/ref>

References

External links

Jepson Manual Treatment, University of California, ''Polygonum bidwelliae''''Polygonum bidwelliae'' - Calphotos Photo gallery, University of California
Polygonum, bidwelliae Endemic flora of California Natural history of the California chaparral and woodlands Natural history of the Central Valley (California) Natural history of Butte County, California Plants described in 1879 Taxa named by Sereno Watson Flora without expected TNC conservation status {{Polygonaceae-stub