4.3 BIOLOGICAL RESOURCES DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 4.3 BIOLOGICAL RESOURCES INTRODUCTION The Biological Resources chapter of the EIR evaluates the biological resources known to occur or potentially occur within the Pine Acres North project (proposed project) site. This chapter describes potential impacts to those resources, and identifies measures to eliminate or substantially reduce those impacts to less-than-significant levels. Existing plant communities, wetlands, wildlife habitats, and potential for special-status species and communities are discussed for the project site. The information contained in this analysis is primarily based on a Biological Resources Evaluation Report for Pine Acres North1 prepared by Sycamore Environmental Consultants (See Appendix G), a Jurisdictional Delineation and Special Status Species Evaluation2 prepared by Gibson & Skordal, LLC (See Appendix H), and an Oak Woodland Assessment3 prepared by Ronald P. Monk Consulting (See Appendix I). EXISTING ENVIRONMENTAL SETTING The following sections describe the regional setting of the site, as well as the existing biological resources occurring in the proposed project area. Regional Setting The proposed project site is located in the Sierra Foothills in the western portion of Amador County, approximately one mile southeast of the community of Pine Grove. The proposed site ranges from approximately 2,500 feet to 2,690 feet above mean sea level (MSL) and is located in the Upper Mokelumne watershed. The majority of soils within the project site were formed in material weathered metasedimentary rock and are well drained with medium to very rapid runoff. Project Setting Land uses located within Amador County are primarily agricultural and open space, with residential and commercial areas in existing cities (See Figure 4.3-1). The proposed project area is surrounded on all sides by existing rural residential subdivisions and open space. The majority of the site generally drains to the northeast by way of an unnamed tributary of Grass Valley Creek. Chapter 4.3 – Biological Resources 4.3 - 1 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Figure 4.3-1 Aerial View of the Proposed Project Area Project Site Chapter 4.3 – Biological Resources 4.3 - 2 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Figure 4.3-2 Connection Between Channel 1 and Navigable Waters Chapter 4.3 – Biological Resources 4.3 - 3 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Hydrology The majority of the site drains to the northeast by way of an unnamed intermittent tributary (Channel 1) of Grass Valley Creek (See Figure 4.3-2). Water from Grass Valley Creek sequentially flows into Sutter Creek, Dry Creek, and the navigable Mokelumne River. Soils The project site soils consist of two soil types, Sites very rocky loam, three to 16 percent slopes (SrC) and Sites very rocky loam, 16 to 51 percent slopes (SrE). Sites very rocky loam, three to 16 percent slopes (SrC) The SrC soil type is well drained, moderately deep, and generally associated with undulating to rolling hill and ridges as well as strong sloping foot slopes in mountainous areas. Rock outcroppings compose approximately 10 to 25 percent of the surface. The soil is derived from metasedimentary rock, mostly slate, schist, and intrusive rock. Sites very rocky loam, 16 to 51 percent slopes (SrE) The SrE soil type is well drained, moderately deep, and generally associated with undulating to rolling hill and ridges as well as strong sloping foot slopes in mountainous areas. Rock outcroppings compose up to 25 percent of the surface. The soil is derived from metasedimentary rock, mostly slate, schist, and intrusive rock. On-Site Vegetation Communities The site is dominated by foothills pine-oak forest. Tree species consist primarily of ponderosa pine (Pinus ponderosa), canyon live oak (Quercus chrysolepsis), black oak (Quercus keloggii), incense cedar (Calocedrus decurrens), and big-leaf maple (Acer macrophyllum). The understory is composed of Himalayan blackberry (Rubus procerus), bind weed (Convolvulus arvensis), soft chess (Bromus mollis), ripgut brome (Bromus diandrus), blue wild-rye (Elymus glaucus), poison oak (Toxicondendron diversilobum), chaparral honeysuckle (Lonicera interrupta), and snowberry (Symphoricarpos albus). Plant Species Observed On-Site Gibson and Skordal conducted a field survey on November 4, 2008 and observed a total of 50 plant species on-site (See Table 4.3-1). Table 4.3-1 Plant Species Observed Within the Proposed Project Area Scientific Name Common Name Acer macrophyllum big-leaf maple Aira caryophyllea silver hairgrass Alnus sp alder Arbutus menziesii madrone Arctostaphylos sp. manzanita Artemesia douglasiana Douglas' wormwood Chapter 4.3 – Biological Resources 4.3 - 4 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Table 4.3-1 Plant Species Observed Within the Proposed Project Area Scientific Name Common Name Brassica nigra black mustard Briza minor little quaking grass Bromus diandrus (B. rigidus) rip-gut grass Bromus mollis soft chess Calocedrus decurrens incense cedar Carex sp. sedge Ceanothus cuneatus buckbrush Centaurea solstitialis yellow star-thistle Convolvulus arvensis bindweed Cynosurus echinatus dogtail Cyperus sp. umbrella sedge Dactytis glomerata orchard grass Elymus glaucus blue wild-rye Equisetum sp horsetail Eriodictyon sp yerba santa Galium bifolium bedstraw Grindelia sp. gum weed Hypericum perforatum kalamath weed Juncus balticus baltic rush Juncus bufonius toad rush Lonicera interrupta honeysuckle Lotus purshianus Spanish clover Marrubium vulgare common horehound Pinus lambertiana sugar pine Pinus ponderosa ponderosa pine Plantago lanceolata English plantain Polygonum sp, smartweed Pseudotsuga menziesii Douglas fur Pteridium aquilinum var. pubescens bracken fern Quercus chrysolepis canyon live oak Quercus douglasii blue oak Quercus kelloggi black oak Quercus wislizenii interior live oak Rhamnus sp. buckthorn Rubus discolor Himalayan blackberry Rubus laciniatus cut-leaved blackberry Rubus parviflorus thimbleberry Rumex acetosella sheep sorrel Silybum marianum milk thistle Symphoricarpos acutus snowberry Toxicodendron diversilobwn poison oak Tragopogon sp. salsify Verbascum thapsus wooly mullein Vida villosa winter vetch Source: Gibson & Skordal, LLC, Jurisdictional Delineation and Special Status Species Evaluation November 2008. Chapter 4.3 – Biological Resources 4.3 - 5 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Special Status Species Table 4.3-2 provides a summary of the listing status and habitat requirements of sensitive species that have been documented in the project vicinity or for which there is potentially suitable habitat in the area. This table also includes an assessment of the likelihood of occurrence of each of these species on the site. The evaluation of the potential for occurrence of each species is based on the distribution of regional occurrences (if any), habitat suitability of the site, and field observations. The table includes sensitive species recorded in the CNDDB (2008) for the Fiddletown, Aukum, Omo Ranch, Amador City, Pine Grove West Point, Jackson, Mokelumne Hill, and Rail Road Flat United States Geological Survey (U.S.G.S) quadrangles. While the site may have historically provided habitat for a subset of the sensitive species listed in Table 4.3-2, the likelihood of occurrence of listed, candidate, and other sensitive species within the project area is considered generally low, as the site contains few habitat attributes for sensitive species that occur in the region. Further analysis is included in this Draft EIR only for species that are known to be present, have a potential for occurrence, or have been noted as present within the project area. Special-Status Plant Species The CNDDB records several special-status plant species as occurring within the vicinity of the study area including Pleasant Valley mariposa-lily (Calochortus clavatus var. avius), Red Hills soaproot (Chlorogalum grandiflorum), Tuolumne button-celery (Eryngium pinnatisectum), Brisbee Peak rush-rose (Helianthemum suffrutescens), Parry’s horkelia (Horkelia parryi), and prairie wedge grass (Sphenopholis obtusata). Though none are federally listed, they have been identified by the California Native Plant Society as species that are potentially threatened to some degree. Pleasant Valley mariposa-lily favors lower montane coniferous forest between 1,000 and 5,900 feet in elevation, and is associated with Josephine silt loam and volcanic soils. Brisbee Peak rush-rose and Red Hills soaproot have been documented in the Gabbro soil regions, but are known to grow on other soils types as well. Both occur in chaparral, but Red hills soaproot is also found in cismontane woodlands and lower montane coniferous forest. Parry’s horkelia is a perennial herb, which is presently threatened by commercial clay mining. The herb grows in chaparral and cismontane woodlands, blooms from April to June, and is found in El Dorado, Amador, Calaveras, and Mariposa counties. Tuolumne button-celery occurs in vernal pools, but is also found in other habitats such as cismontane woodlands and lower coniferous montane forests. Prairie wedge grass grows in moist areas such as cismontane seeps, stream banks, and ponds. Chapter 4.3 – Biological Resources 4.3 - 6 DRAFT EIR PINE ACRES NORTH NOVEMBER 2009 Table 4.3-2 Special-Status Species and Sensitive Natural Communities that Potentially Occur or Were Observed Within the Project Area Potential for Federal State CNPS Occurrence in the Study Common Name Scientific Name Status1 Status2 List3