Vegetation - Modoc Plateau - Shinn, Likely, and Snowstorm Mountains - 2020 [ds2877]

Under contract to the California Department of Fish and Wildlife (CDFW), The Geographical Information Center (GIC) was tasked with creating a fine-scale vegetation and land use map of portions of the Modoc Plateau in northeastern California. The mapping effort was done in a two phases. The first phase started in 2016 and covered the ecoregion subsections named Cottonwood-Skedaddle Mountains, Likely Mountain, and the eastern portion of Eagle Lake-Observation Peak (Miles and Goudey 1997) which covered nearly 1.1 million acres. The second phase began in 2018 and covered the ecoregion subsections named Devil’s Garden and Adin Mountains, which covered an additional 866,228 acres. This map was produced during phase one of the project and covers approximately 1,091,702 acres in eastern Lassen and southern Modoc counties. The vegetation map followed guidelines set forth by the National Vegetation Classification System (NVCS) and A Manual of California Vegetation (MCV). It is an Alliance level map overall, with photo-interpreters attempting to map to the more specific Association level when they were confident to go to that level of detail. The GIC used 2016 NAIP imagery for mapping. Accuracy assessments were performed in 2018 and 2020. The minimum mapping unit (MMU) varies by vegetation type. For standard vegetation polygons the MMU is 1 acre. For wetland and riparian areas, the MMU is 0.25 acres. Polygons on the border of the mapping boundary did not have a MMU. For Agriculture and Urban areas, the MMU is 1 acre For Water, the MMU is 1 acre (with the exception of small earthen dams which went down to .25 acres).More information can be found in the project report, which is bundled with the vegetation map published for BIOS here: https://filelib.wildlife.ca.gov/Public/BDB/GIS/BIOS/Public_Datasets/2800_2899/ds2877.zip