The California Department of Fish and Game (CDFG) contracted with the California Native Plant Society (CNPS) and Aerial Information Systems (AIS) to produce an alliance-level, vegetation classification and map of Western Riverside County, California. The resulting classification and map products will be used to help establish a monitoring basis for the vegetation and habitats of the Western Riverside County Multi-Species Habitat Conservation Plan (MSHCP). The plan aims to conserve over 500,000 acres of land out of the 1.26 million acre total. This area is the largest MSHCP ever attempted and is an integral piece of the network of Southern California Habitat Conservation Plans and Natural Community Conservation Planning (Dudek 2001, Dudek 2003). Riverside County is one of the fastest growing counties in California, as well as one of the most biodiverse counties in the United States. A wide array of habitats are found within the non-developed lands in Western Riverside County, including coastal sage scrub, vernal pools, montane coniferous forest, chaparral, foothill woodland, annual grassland, and desert. In the CNPS contract, vegetation resources were assessed quantitatively through field surveys, data analysis, and final vegetation classification. Field survey data were analyzed statistically to come up with a floristically-based classification. Each vegetation type sampled was classified according to the National Vegetation Classification System to the alliance level (and association level if possible). The vegetation alliances were described floristically and environmentally in standard descriptions, and a final key was produced to differentiate among 101 alliances, 169 associations, and 3 unique stands (for final report, see https://nrm.dfg.ca.gov/FileHandler.ashx?DocumentID=18245). In a parallel but separate effort by AIS (as reported in this dataset), vegetation mapping was undertaken through interpretation of ortho-rectified, aerial photographs for vegetation signatures in color infrared (CIR) and in natural color (imagery flown in winter or summer). A detailed map has been produced through the following process: 1) hand-delineation of polygons on base CIR imagery, 2) digitization of polygons, and 3) attribution of the vegetation types and overstory cover values. The map was created in a Geographic Information System (GIS) digital format, as was the database of field surveys. The dataset was produced through an on-screen photo interpretation procedure using three sets of geo-referenced imagery. The data is classified to a floristic classification derived through clustering analysis procedures based on species dominance and significance. The classification is based on the MCV (Manual of California Vegetation) in which 103 alliances and 169 floristic associations have been defined for the study area. Over 3300 full plot and reconnaissance points have been used in helping classify the mapped polygons. Mapped polygons are classified to either an association, alliance or mapping unit which may be an aggregation of associations or alliances. The dataset encompasses the western portions of Riverside County from the county boundary on the west eastward to the summit of the San Jacinto Mountains and Anza valley.

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Under contract to the California Department of Fish and Wildlife (CDFW), the North State Planning and Development Collective (NSPDC) created a fine-scale vegetation map of portions of the Sierra Nevada mountains around Lake Tahoe and the adjacent Modoc Plateau. CDFW''s Vegetation Classification and Mapping Program (VegCAMP) provided in-kind service to allocate and score the Accuracy Assessment. The mapping study area consists of approximately 1.6 million acres, covering portions of Sierra, Plumas, Placer, Nevada, Modoc, and Lassen counties. Work was performed on the project between 2019 and 2023. The purposes of the project include assisting land managers in decision-making, fire and fuel management, protecting endangered species and habitats, protecting cultural and natural resources, habitat connectivity, habitat restoration, conservation prioritization, and informed development. NSPDC staff conducted 434 Rapid Assessment and Releve surveys across the mapping area in the summer of 2019 to gather vegetation data to be used in the development of a vegetation classification for the project area.VegCAMP developed the floristic vegetation classification used for the project. The floristic classification follows protocols compliant with the Federal Geographic Data Committee (FGDC) and National Vegetation Classification Standards (NVCS).The vegetation map was produced applying heads-up digitizing techniques using a 2018 base of one-meter National Agricultural Imagery Program (NAIP) imagery (true-color and color infrared), in conjunction with ancillary data and imagery sources. Map polygons are assessed for Vegetation Type, Percent Cover, Exotics, Development Disturbance, and other attributes. The minimum mapping unit (MMU) is 1 acre; exceptions are made for wetlands and riparian types, which were mapped to a 1/4 acre. Breaks on overstory cover were done at 3 acres.Field reconnaissance and the Accuracy Assessment enhanced the overall map quality. There were a total of 107 mapping classes. The overall Fuzzy Accuracy Assessment rating for the final vegetation map,at the Alliance, Group, and Macrogroup levels, is 81.7% percent.

Under contract to the California Department of Fish and Wildlife (CDFW), the North State Planning and Development Collective (NSPDC) created a fine-scale vegetation map of portions of the Sierra Nevada mountains around Lake Tahoe and the adjacent Modoc Plateau. CDFW''s Vegetation Classification and Mapping Program (VegCAMP) provided in-kind service to allocate and score the Accuracy Assessment. The mapping study area consists of approximately 1.6 million acres, covering portions of Sierra, Plumas, Placer, Nevada, Modoc, and Lassen counties. Work was performed on the project between 2019 and 2023. The purposes of the project include assisting land managers in decision-making, fire and fuel management, protecting endangered species and habitats, protecting cultural and natural resources, habitat connectivity, habitat restoration, conservation prioritization, and informed development. NSPDC staff conducted 434 Rapid Assessment and Releve surveys across the mapping area in the summer of 2019 to gather vegetation data to be used in the development of a vegetation classification for the project area.VegCAMP developed the floristic vegetation classification used for the project. The floristic classification follows protocols compliant with the Federal Geographic Data Committee (FGDC) and National Vegetation Classification Standards (NVCS).The vegetation map was produced applying heads-up digitizing techniques using a 2018 base of one-meter National Agricultural Imagery Program (NAIP) imagery (true-color and color infrared), in conjunction with ancillary data and imagery sources. Map polygons are assessed for Vegetation Type, Percent Cover, Exotics, Development Disturbance, and other attributes. The minimum mapping unit (MMU) is 1 acre; exceptions are made for wetlands and riparian types, which were mapped to a 1/4 acre. Breaks on overstory cover were done at 3 acres.Field reconnaissance and the Accuracy Assessment enhanced the overall map quality. There were a total of 107 mapping classes. The overall Fuzzy Accuracy Assessment rating for the final vegetation map,at the Alliance, Group, and Macrogroup levels, is 81.7% percent.

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