Rare S1-S3 Alliances: Vegetation Carrizo Plain National Monument, Ecological Reserve and Adjacent Elk Range [ds1094]

The California Department of Fish and Wildlife (CDFW) Vegetation Classification and Mapping Program (VegCAMP) has created a fine-scale vegetation map of part of the range of the American Ranch and Chimineas Ranch tule elk herds. This section of the elk range is adjacent to the Carrizo Plain National Monument and the Chimineas Ranch Unit of the Carrizo Plain Ecological Reserve, both of which have been previously mapped. This map has been seamed to the vegetation map of the Chimineas Ranch completed by VegCAMP (VegCAMP 2010) and the map of the Carrizo Plain National Monument produced by the California Native Plant Society (Stout et al. 2013), and completes the range of these two elk herds in San Luis Obispo County, California. Like those maps, this mapping follows Survey of California Vegetation, Federal Geographic Data Committee (FGDC), and National Vegetation Classification (NVC) standards (FGDC 2008, Jennings et al. 2009). The map legend is based on the classification in Stout et al. (2013), with slight modifications as discussed in Appendix C of the report, which is available here: https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=92951. Reconnaissance-level sampling of vegetation stands in the project area was conducted in the spring of 2013. Polygons were drawn using heads-up digitizing with true color 1-foot aerial imagery from August 1, 2007 as the map base. Supplemental imagery included National Agricultural Imagery Program (NAIP) true color and color infrared (CIR) 1-meter resolution data from 2010–2012, Bing imagery, and current and historical imagery from Google Earth. The minimum mapping unit (MMU) is 1 acre, with the exception of wetland types, which have an MMU of ½ acre. Mapping is to the NVC hierarchy Association, Alliance, or Group level based on the ability of the photointerpreters to distinguish types based on all imagery available and on the field data. Two sub-Group level mapping units were used in instances where the vegetation types could not differentiated on the imagery. The first mapping unit is composed of the Salvia leucophylla, Eriogonum fasciculatum, Artemisia californica, and Artemisia californica-Eriogonum fasciculatum Alliances; the second is composed of the Atriplex polycarpa and Atriplex canescens Alliances. Accuracy assessment (AA) data was collected in spring of 2014. Map accuracy was calculated to be 89%; corrections were made to the map based on the AA data to increase the final accuracy.