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Vantage to Pomona Heights Chapter 3 230 kV Transmission Line Project FEIS Affected Environment PAGE 3-4 3.2.2 Current Conditions and Trends, Regional Overview 3.2.2.1 Vegetation Cover Types Vegetation cover types were assessed using aerial photos, JBLM YTC vegetation data (JBLM YTC 2002), GAP data, and fire history data. This information is provided in Appendix A: Vegetation and Fire History Map and Appendix B-3: Special Status Plants Reports. A summary of the vegetation cover types within the Project area is presented in Table 3.2-1 and is described for each route segment in Section 3.2.4. The Project study area lies within the Columbia Plateau ecoregion. The Columbia Plateau is an arid sagebrush (Artemisia spp.) steppe and grassland that is surrounded by ecoregions that are typically moister, forested and mountainous (U.S. Environmental Protection Agency [USEPA] 2010). Plant communities within the Project study area and its immediate vicinity have been altered by roads, urban development, military activities, livestock grazing, agriculture, noxious weeds and invasive species, and fire. Shrub-steppe habitat is located primarily west of the Columbia River and agricultural development is located east of the Columbia River and south of the Saddle Mountains. Vegetation cover types present within the Project study area are described below. Agriculture Agricultural lands in the Project study area are primarily used for cultivation of fruit trees, vineyards, and row crops. Livestock grazing occurs on both public and private lands. For more information on farming and grazing activities in the Project study area, refer to Section 3.4 - Land Jurisdiction and Land Use. Annual Grassland Annual grasses present in the Project study area are comprised of field brome (Bromus arvensis) and cheatgrass (Bromus tectorum). Bulbous bluegrass (Poa bulbosa), while perennial, is functionally similar to these non-native annual grasses and is also included in this cover type. Annual grasslands cover approximately 20.4 percent (36,798.6 acres) of the Project study area. Bitterbrush/Perennial Grassland Antelope bitterbrush (Purshia tridentata) with a perennial bunchgrass understory of bluebunch wheatgrass (Pseudoroegneria spicata), Sandberg bluegrass (Poa secunda), needle and thread grass (Hesperostipa comata), and Thurber’s needlegrass (Achnatherum thurberianum) occurs on a small portion of the Project study area (5.2 acres; less than 0.1 percent). Forb For the Project study area, forbs are typically present and included as components of other vegetation cover types (e.g., sagebrush/perennial grassland). However, there are locations where forbs are the most prevalent vegetation type, typically along or near the tops of ridges or hills. Forbs comprise approximately 1.1 percent (2,011.7 acres) of the Project study area and consist of narrowleaf mock goldenweed (Nestotus stenophyllus) and thyme-leaf buckwheat (Eriogonum thymoides) with a perennial grass understory (JBLM YTC 2002). Perennial Grassland Perennial grasslands include vegetation dominated by bunchgrasses with occasional shrubs. Principal perennial grasses within the Project study area include: crested wheatgrass (Agropyron cristatum), bluebunch wheatgrass, Sandberg bluegrass, Idaho fescue (Festuca idahoensis), needle and thread grass, squirreltail (Elymus elymoides), and Thurber’s needlegrass. Perennial grasslands cover approximately 5.6 percent (10,022.1 acres) of the Project study area.