SU0012635 - Laserfiche WebLink

Home Browse Search

Plant Communities Vegetation observed on the site is classified below into communities based on those described by Holland in Preliminary Description of Terrestrial Natural Communities of California (1986). The project site comprises three distinct plant communities: non-native grassland, northern vernal pool and swale, and riparian scrub. A listing of all plant species observed on the project site is provided in Appendix A. Please refer to Figure 1, Biological Resources, for the specific location of all plant communities discussed. Non-native Annual Grassland Non-native annual grassland occurs throughout the project site. In particular, it grows on all areas not yet subject to quarrying activities in both the northern and southern half of the site. On the southern half of the property the annual grasslands are transected by seasonal swales and pools. Typical grass species which grow in grassland communities include wild oat (Avena fatua), soft chess brome (Bromus mollis), and fescue (Vidpia megahva). A variety of annual herbaceous species including filaree (Erodium cicutaritun), bindweed (Convolvdits arvensis), and yellow star thistle (Centaurea solstitialis) also grow within the grassland. Northern Vernal Pool and Swale Within the southeastern portion of the site there occur several vegetation lined swales and associated low spots which serve as seasonal pooling areas. Plant species that grow within this habitat are specially adapted to periodic inundation and saturated soil conditions. These low areas within the grassland are identified on the Biological Resources Map with a creek symbol. Vernal pool species observed within these areas include meadow foam (Limnanthes sp.), popcorn flower (Plagiobothrvs sp.), and Blennosperma (Blenosperma sp.). Riparian Scrub Several stockponds and a drainage which hydrologically connects them, occur in the central portion of the site. Scattered throughout this drainage are several stands of riparian vegetation. The dominant species observed in this community is willow (Salix sp.). Because this drainage will not be included within the project expansion areas a detailed analysis of this area was not conducted. Quarry excavation operations will not be conducted within 100' from the center of the stream. Sensitive Plant Species There are 17 sensitive plant species identified by the California Native Plant Society in San Joaquin County (Smith and Berg, eds. 1988). Of these, only three species could potentially be on the project site. These three species are described in Table 1. Field surveys were conducted in February 1991 by Condor biologists. Some of the species listed below do not typically flower until later in the spring, and presence or absence of these species is unknown at this time. Additional surveys should be conducted in April, May, and August 1991 to conclusively verify presence or absence of these species on the project site. No state or federally listed threatened or endangered plant species were observed on the project site during field surveys. The following provides a description of other potentially occurring sensitive plant species and the results of field surveys for these species on the project site. CONDOR