The Knoll-Top. Several Other Small Structures Also Occur on the Lower Slopes in This Area
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the knoll-top. Several other small structures also occur on the lower slopes in this area. The property was in agricultural use in the past as a chicken farm. The remnants of one structure (a metal barn) used to house chickens is near the northwestern corner of the site; several terraced pads also occur on the northern and western portions of the property where other similar structures were formerly located. Open areas have since been disced and mowed on a regular basis for weed abatement and fire safety purposes. One ephemeral drainage exists on the property, on the southern portion of the property, near its eastern boundary. It originates at the outflow of an 18” culvert that runs under the present access road. From the culvert exit it runs in an excavated straight ditch for approximately 100 feet. At this point there is no longer a distinct channel. When water is present, it likely sheet flows across a mowed area, south and east into a riparian woodland area. A channel runs generally south through the riparian woodland, and crosses the property boundary. It continues off-site through agricultural land to eventually enter the floodplain of the San Luis Rey River. The drainage is not noted as a continuous blue-line or broken blue-line on the USGS topo map (Figure 2). A residential subdivision is west of the property, and a golf course is immediately north. Rural- residential development is adjacent to the south, and active agricultural fields are to the east across Wilshire Road. To the northwest of the property is a large detention basin and riparian revegetation area which was previously established as mitigation for impacts resulting from development of the golf course to the north and residential development to the west. None of this habitat occurs within the subject property’s boundaries. 3. Methods and Survey Limitations Affinis conducted an initial biological reconnaissance of the site in 2007. An updated survey was done by Affinis biologists Mike Busdosh and Marcia Adams on August 16, 2013. Kevin Clark of Clark Biological Services also participated in the survey to focus on avian species using the site. The weather was clear and warm, with slight variable breezes. Most of the site was traversed on foot. Additionally, the California Department of Fish and Wildlife’s Natural Diversity Data Base (NDDB) was accessed to determine if any sensitive species had been reported from the project area. It is the intent of this project to avoid significant impacts with project design. As noted, delineation of jurisdictional waters was done by Affinis’ Mike Busdosh. Survey and evaluation of least Bell’s vireo was done by Kevin Clark. As these resources are both largely associated with the riparian woodland area, they compared notes after each had done his field work. All of the project is to be west of the riparian woodland. To guide project design, these biologists together walked the length of the jurisdictional water and riparian woodland to delineate the western limits of jurisdictional waters and least Bell’s vireo potential foraging area. A single 2 delineation line was drawn using a hand-held GPS, to include the maximum area of both of these sensitive resources. 3. Results a. Vegetation The North County Multiple Habitat Conservation Plan has been adopted by SANDAG as the governing document for the Subregional Multiple Habitat Conservation Program (MHCP). The City’s SAP was prepared to be consistent with the MHCP. While the SAP does not define “disturbed lands” versus “nonnative (annual) grasslands” versus “Agricultural (including fallow) Land Appendix F of the MHCP provides the following: “Annual (Nonnative) Grassland. Annual grassland is a mixture of annual grasses and broad-leaved, herbaceous species. Annual species comprise from 50 percent to more than 90 percent of the vegetative cover, and most annuals are non-native species. Nonnative grasses typically comprise at least 30 percent of the vegetation, although this number can be much higher in some years and lower in others, depending on land use and climatic conditions. Usually, the annual grasses are less than 1 m (3 ft) in height, and form a continuous or open cover. Emergent shrubs and trees may be present, but do not comprise more than 15 percent of the total vegetative cover. Characteristic annual grassland species include foxtail chess (Bromus madritensis ssp. rubens), ripgut grass (Bromus diandrus), wild oats (Avena spp.), fescues (Vulpia spp.), red-stem filaree (Erodium cicutariaum), mustards (Brassica spp.), lupines (Lupinus spp.), and goldfields (Lasthenia spp.), among others.” “Disturbed Land. Disturbed land includes area in which the vegetative cover comprises less than 10 percent of the surface area (disregarding natural rock outcrops) and where there is evidence of soil disturbance and compaction (e.g., grading); or where the vegetative cover is greater than 10 percent, there is soil surface disturbance and compaction, and the presence of building foundations and debris (e.g., irrigation piping, fencing, old wells, abandoned farming or mining equipment) resulting from legal activities (as opposed to illegal dumping). Vegetation on disturbed land (if present) will have a high predominance of nonnative, weedy species such as Russian thistle (Salsola tragus), telegraph weed (Heterotheca grandiflora), horehound (Marrubium vulgare), and sow-thistle (Sonchus oleraceus). Although nonnative grasses may be present on disturbed land, they do not dominate the vegetative cover. Examples of disturbed land include recently graded firebreaks, graded construction pads, construction staging areas, off-road vehicle trails, and old homesites.” “Agricultural (including Fallow) land. Active agricultural land includes lands that are currently disturbed by cultivation or other agricultural activities involving crop 3 production practices (e.g., nurseries, orchards, field crops, improved pastures). Fallow agricultural land is land that has been previously disturbed by cultivation, but is currently out of production. Vegetation on fallow land is dependent, in part, on prior crops and crop culture practices. Depending on the type and intensity of disturbance, fallow fields may support either annual grassland or disturbed vegetative associations. Lands that are not currently in production but that are identified in a subarea plan as agriculture and have been cultivated in 3 of the last 5 years or according to accepted cultural practices (as defined by the County Agriculture Commission) will be considered fallow agriculture, regardless of species composition. Conversely, agricultural lands that have not been cultivated in 3 of the last 5 years, or that are proposed for conversion to non-agricultural land uses (e.g., residential, commercial, industrial) shall be mapped and mitigated according to the actual vegetation type (e.g., annual grassland or disturbed land) based on vegetative characteristics, without regard to current or historic land uses.” Based upon these guidelines, five vegetative associations/habitat types were mapped on-site (Figure 5). These include: Urban/developed (9.6 acres). Areas supporting structures, landscaping, and paved areas were mapped as urban/developed land. Disturbed land (1.3 acres). Areas that are largely devoid of vegetation were mapped as disturbed land. There are also remnants of old irrigation lines in some areas, especially near the riparian habitat. Pasture (1.3 acre). This area is along the northeastern property boundary and consists of a small pad that was previously fenced and irrigated. It was last used for horse grazing in 2009. Annual grassland (24.6 acres). Annual grassland, consisting primarily of Bermuda grass (Cynodon dactylon) and bromes (Bromus spp.), is highly degraded and largely dominated by fennel (Foeniculum vulgare), horehound (Marrubium vulgare), and mustards (Brassica spp). As noted above, these areas are mowed and/or disced on a regular basis for weed abatement/fire safety purposes. A few individual native plants such as goldenbush (Isocoma veneta), coyote brush (Baccharis piluaris), and deerweed (Lotus scoparius) were noted in some areas of the annual grassland, but no native scrub habitats are present on-site. Riparian woodland (0.8 acres). A strip of riparian woodland is present along a portion of the eastern site boundary. It is dominated by arroyo willow (Salix lasiolepis) and black willow (S. gooddingii). Weedy tree species such as ornamental palms and tamarisk (Tamarix spp.) are present in some areas. The understory supports other weedy species such as castor bean (Ricinus communis) and bristly ox tongue (Picris echioides); as well as native mulefat (Baccharis sarothroides), coyote brush (B. pilularis), and bulrush (Scirpus spp.) in moister areas. No 4 standing or flowing water was present at the time of the survey. The riparian habitat is isolated and does not continue up or downstream due to ongoing agricultural activities and/or urban development off-site. A complete list of plant species found on-site is included in Appendix 1. b. Wildlife Avifauna. Nineteen bird species were observed on-site (Appendix 2). Three raptors were noted flying over the site, including turkey vulture, red-tailed hawk, and American kestrel. Birds common to agricultural and urbanized areas were Eurasian collared dove, mourning dove, northern mockingbird, black phoebe, and California towhee. Additionally, common peafowl and domestic chickens freely roam much of the site. Song sparrow and common yellowthroat were found in the on-site