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]

References

  1. ^ "NatureServe Explorer 2.0".
  2. ^ Calflora taxon report, University of California, Polygonum marinense T. Mert. & Raven, Marin knotweed
  3. ^ a b Flora of North America, Polygonum marinense T. R. Mertens & P. H. Raven, 1965. Marin knotweed
  4. ^ Mertens, Thomas Robert & Raven, Peter Hamilton. 1965. Madroño 18(3): 87–88
  5. ^ California Native Plant Society Rare Plant Profile

External links