(Calystegia stebbinsii)
Stebbins’ morning-glory is a California endangered plant species, which means that killing or possessing the plant is prohibited by the California Endangered Species Act (CESA). This species is also listed as endangered under the federal Endangered Species Act. Stebbins’ morning-glory is a low-growing perennial herb with large white flowers that bloom from May to June. It is distinguished from other California morning-glories by its uniquely-shaped leaves. Stebbins’ morning-glory maintains a dormant seed bank or rootstock that germinates following fire or other ecological disturbance that may weaken the seed coat (scarification). Stebbins’ morning-glory also appears to be susceptible to shading out because it is much less abundant or missing entirely in older stands of chaparral on appropriate soils, so the species is thought to depend on a disturbance regime to persist.
Historically, Stebbins’ morning-glory has only been found in two areas of the northern California foothills in El Dorado and Nevada Counties. The California Natural Diversity Database (CNDDB) currently lists 13 occurrences of Stebbins’ morning-glory, 9 of which are believed to still exist. Survey data for most of these occurrences is from 2007 and 2008, and at that time one occurrence had approximately 15,000 plants, one had over 1,000 plants, and the remaining occurrences had less than 100 plants.
The major threats to Stebbins’ morning-glory are all related to urbanization, and include habitat loss and fragmentation, alteration of the natural fire regime, and the suppression of natural disturbance. Proposed developments also threaten remaining habitat in western El Dorado County. In its Recovery Plan for Gabbro Soil Plants of the Central Sierra Nevada Foothills (PDF), the U.S. Fish and Wildlife Service recommends creating a preserve that will protect existing populations of Stebbins’ morning-glory and other related California rare plants that are found in the same area. This preserve would require a detailed management plan that includes recreating a disturbance regime that facilitates the emergence of new populations of Stebbins’ morning-glory. Other state-listed plant species that are associated with Stebbins’ morning-glory would also likely benefit from such a disturbance regime.
CDFW may issue permits for Stebbins’ morning-glory pursuant to CESA, and you can learn more about the California laws protecting Stebbins’ morning-glory and other California native plants. Populations of Stebbins’ morning-glory occur in CDFW’s North Central Region. More information is also available from the U.S. Fish and Wildlife Service Species Profile for Stebbins’ morning-glory.
Updated 9/23/2013