Laguna Watershed Knowledgebase

Butte County meadowfoam (BCM) is a Federally and State listed endangered plant that inhabits vernal pools near Chico, California. Extant occurrences of BCM are geographically isolated, persisting in small habitat fragments that are vulnerable to anthropogenic and stochastic environmental impacts. Loss of any one occurence may represent a significant loss of the total amount of genetic diversity for the species. Low levels or lack of gene flow between extant occurrences can create a discrete population structure accross the landscape and cause genetic isolation. An earlier BCM isozyme study (Dole & Sun 1992) showed low levels of genetic diversity and regional distinction of populations. Small, declining occurrences are at high risk of extinction as they are lacking the adaptive potential necessary to withstand chance catastrophes. The purpose of this study was to reassess the genetic similarity and isolation between new and previously studied extant populations of BCM. We assessed genetic diversity within populations and range-wide genetic structure between populations with a highly polymorphic microsatellite system.