Recovery Plan for Casissonia benitensis (San Benito Evening-Primrose)

摘要

Camissonia benitensis (San Benito evening-primrose) is a small ephemeral annual plant that occupies a fragile and geologically transitory habitat. Camissonia benitensis is known from 53 suboccurrences (mapped sites) that are clustered into 27 occurrences; four of these suboccurrences are sites where Camissonia benitensis was introduced. Only a fraction of the suboccurrences support primrose populations in any given year, and most of these populations are small (under 100 individuals). About two-thirds of the occurrences have been adversely affected by off-road vehicle recreation. The core area for the species consists of habitat within Clear Creek Canyon. This watershed is central to the recovery of the species, because it contains 70 percent of the occurrences managed by the Bureau and about 75 percent of the total number of individuals of Camissonia benitensis.