Polygonum_marinense
Polygonum marinense
Species of flowering plant
Polygonum marinense is a rare North American species of flowering plants in the buckwheat family known by the common name Marin knotweed. It is endemic to California, where it is known from just a few locations north and east of San Francisco Bay.[2]
The taxonomy of the plant is uncertain. It has been suggested that the species may be native to the Mediterranean, and that the California specimens may actually be introduced.[3][4] If, however, it is a true Bay Area endemic, the plant is rare and threatened by habitat destruction and disturbance.[5] It is a resident of salt marsh and other wet coastal habitat.
Polygonum marinense is an annual herb producing a ribbed, reddish stem growing prostrate or erect to a maximum height near 40 centimeters (16 inches). The narrow oval or lance-shaped leaves are alternately arranged along the slender stem. Each reddish leaf has a funnel-shaped stipule that wraps around the leaf base to form an ochrea. Flowers occur in the leaf axils. They are greenish with white or pink-tinged edges.[3]
