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Knowledge gaps regarding the greenhouse propagation of rare, fire-adapted plant species can impede community level conservation efforts that require fire and active revegetation as management tools. Ericameria fasciculata is a rare shrub endemic to the maritime chaparral community of the central California coast and a listed species of concern. Prescribed burning is actively used in maritime chaparral to maintain community composition and conserve several species of concern with known affinities for fire-related conditions. No study has investigated the seed viability and germination requirements for E. fasciculata. The goal of this study was to ascertain the (1) greenhouse propagation potential of E. fasciculata for planned restoration efforts and (2) to determine if fire-related conditions inhibit or promote E. fasciculata germination. Seed dissection and viability testing indicated that a large percentage of seed were empty or inviable. A greenhouse study examined the potential for fire-related germination cues from heating, light, and charate. Heating and charate had negative effects on seed germination. The combination of heating and charate treatments were particularly lethal. Exposure to light or the addition of GA3 had no influence on germination rates. Results suggest that seed germination of E. fasciculata is inhibited by fire and, therefore, this species is dependent on seedling establishment between fire events.
Cape ivy (Delairea odorata Lem.) was found to occur throughout coastal California and southern Oregon. It was most abundant in urbanized coastal areas such as the San Francisco Bay, and Santa Cruz, Monterey, San Luis Obispo, Santa Barbara and Los Angeles counties. Field observations showed Cape ivy to occur in seven different broad community types, including both riparian and non-riparian areas. Of the two morphological forms, the exstipulate type occurred more frequently at the northern and southern ends of the distribution, and the stipulate type was more common in the middle of the distribution range, from southern Humboldt County to Los Angeles County. Only 21 locations were found that supported both stipulate and exstipulate plants, and they were most often located in urbanized coastal areas. Analysis with GIS determined the elevation, temperature and precipitation ranges that Cape ivy occupies in California. The analysis indicated that Cape ivy occurs at elevations between 0 and 891 meters, annual mean temperatures between 10.5 and 17.7°C, and in areas with annual precipitation ranging between 232 and 2270 mm. An overlay analysis of Cape ivy locations using GIS was also compared with the California Natural Diversity Database sensitive species location information to determine which species might be threatened by Cape ivy expansion. Three sensitive animals and five sensitive plants were expected to have >40% of their occurrences with a 500 m buffer to Cape ivy infestations.
Previous investigations into the morphology of Pyrrocoma liatriformis sensu lato in northern Idaho and adjacent Washington have revealed two distinct morphologies that correspond to their geographical ranges. These same populations and individuals have been analyzed using AFLP data. Over 400 loci were identified among all individuals using two sets of AFLP adaptors. The data are in agreement with the morphological data and separate the populations from the Snake River Canyon/Camas Prairie from those of the Palouse grasslands. Data clustering methodologies using both presence/absence data for all individuals and allele frequencies for each population produced similar results. We suggest the name P. scaberula be resurrected to encompass the populations from the Snake River Canyon and Camas Prairie.
Frasera fastigiata and F. umpquaensis are large, long-lived, perennial herbs with hollow stems, whorled leaves, large nectaries hidden by fringed hoods, and synchronized flowering. They differ in flower color and their ranges are disjunct. Some authors have treated them as conspecific due to their overall morphological similarity. The taxa can be distinguished by isozyme band patterns and by morphological traits including corolla color, relative lengths of corolla and calyx, and calyx lobe shape. Both isozyme differences and morphological differences are not completely fixed, but plants with one atypical feature can be identified by their combination of traits. The taxa should be recognized as distinct species.
Astragalus jaegerianus Munz (the Lane Mountain milkvetch) is a federally endangered species that exists in only four fragmented populations within and adjacent to the U.S. Army's National Training Center, Fort Irwin, CA. Since 1999, our monitored A. jaegerianus populations have consistently declined, and are now 12% of their previous size. A number of subpopulations are in danger of local extinction. The decline of A. jaegerianus has occurred simultaneously with severe drought in the Mojave Desert. These drought conditions began in 1999 and are predicted to continue for decades, or may continue indefinitely under warmer temperature conditions projected by global climate change-type drought. Our results suggest that drought has direct and indirect affects on A. jaegerianus by killing or degrading its host shrubs. Astragalus jaegerianus host shrubs have decreased in shrub volume and cover by roughly 10 percent since the onset of drought, and shrub mortality has been high. Our results show that canopy condition has a profound affect on the microclimate within host shrubs. Furthermore, our results show a significant increase in survival of A. jaegerianus among host plants with more intact canopies. These results support our study hypothesis that drought-related changes to host plant canopies affect A. jaegerianus survival, and represent an indirect negative effect of long-term drought on A. jaegerianus populations.
We conducted a study of Prosartes parvifolia S. Watson, a rare Siskiyou Mountains endemic, currently known from only 15 sites in Del Norte Co., California, and Curry and Josephine counties, Oregon. We found that P. parvifolia is (a) fertile, (b) probably not of hybrid origin, and (c) distinct and worthy of recognition as a species. Unlike congeners, its flowers produce ovaries with a single locule, and are pollinated by bees that buzz pollen from connivent anthers. Nectar is not produced. We provide an expanded description, illustrations, and distribution map for P. parvifolia as well as a key to the Prosartes of northwestern California and southwestern Oregon.
Sedum valens (Crassulaceae) is described from the Salmon River Canyon of central Idaho. Though it shares numerous morphological traits with Sedum borschii and S. leibergii, the species differs strikingly in having myriad leaves packed into rosettes as wide as 1 dm. The leaves are ciliate, a characteristic otherwise unknown in temperate North American Sedum, except in Sedum radiatum, a highly dissimilar species. Further distinguishing characteristics are found in leaf shape, phenology, fruit characteristics and in habitat.
Abies magnifica A. Murray bis var. critchfieldii var. nov. Lanner (Critchfield red fir) is described. The new variety comprises the southernmost Sierra Nevada populations of California red fir. It differs from the typical variety in having smaller cones with protruding cone bracts. Because of the protruding bracts, populations of the new variety have been assumed to be disjuncts of the bracted A. magnifica var. shastensis Lemmon (Shasta red fir), described over a century ago from Mt. Shasta and considered present in NW California and SW Oregon. However, geographic patterns of morphological variation, artificial crossing results, and recent molecular studies indicate that Shasta red fir consists of California red fir introgressed by noble fir (A. procera Rehder), and that the new variety is not hybridized with noble fir.
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