2002 SCB Symposium
Rare plants in Southern California
Rare Plants in Southern California.
Prof. Robert F. Thorne, Taxonomist Emeritus
Selected rare and endemic vascular plants will be illustrated by geographical areas, such as the Channel Islands, coastal areas with vernal pools, the Transverse and Peninsular ranges, Death Valley and Joshua Tree National parks, and other Mojave and Colorado desert areas.
The Floristics of Clay Soil Habitats in Western Riverside County.
Steve Boyd, Curator of the Herbarium, Rancho Santa Ana Botanic Garden, Claremont, CA
Clay soil habitats in western Riverside County occur as island-like patches within a surrounding matrix of well-drained substrates derived largely from granitic bedrock and alluvium. Most are associated with outcroppings of gabbro or volcanic rock, or alluvial and colluvial deposits dominated by these rocks. Clay deposits range in size from extensive areas covering numerous hectares down to locally weathered patches of only a few square meters. Clay soil habitats contribute significantly to western Riverside County's floristic diversity and harbor numerous rare, threatened, and endangered species, including narrow edaphic endemics such as Munz's onion (Allium munzii) and Hammitt's claycress (Sibaropsis hammittii). Understanding the subtle floristic patterns expressed on clay soils derived from different parent rock types and under different hydrologic regimes will be essential for selection and management of ecological reserves within the region.
Botanical Exploration in Southern California Continues to Yield New (and usually Rare) Species.
Mark A. Elvin, Biologist, Dudek and Assoc., Encinitas, CA., Museum Scientist, UCI, Irvine, CA., and Andrew C. Sanders, Curator of the Herbarium, UCR, Riverside, CA.
The Southern California Floristic Province has been well surveyed and documented (relatively speaking), yet new species continue to be discovered and described. Selected new plant species from Southern California will be discussed and illustrated.
Rare Plants of Ventura County.
David L. Magney
The Ventura County flora has approximately 2,000 taxa, based on extensive collecting and herbaria research conducted by the author. Topography and habitats are quite varied in Ventura County, ranging from sea level to 8,831 feet on Mt. Pinos, and includes coastal dunes, lagoons, and marshes, to coastal sage scrub, chaparral, oak woodlands, varied riparian habitats, pinyon-juniper woodland, yellow pine forest, and subalpine habitats. Nearly half of the native flora consists of taxa that are listed by CNPS, or have ten or fewer occurrences in the county. The presentation will discuss methods used, rationale, and results of the floristic and rarity work that the author has conducted on the Ventura County flora
Kate Kramer, CDFG, USFWS, CNPS
Representatives from each agency/organization
will discuss laws, protection and conservation of rare plants in southern California. Following their brief talk will be a question and answer period.