In December 2019, the Vegetation Classification and Mapping Program (VegCAMP) updated the “map of vegetation maps” in BIOS that shows footprints of fine-scaled vegetation maps: Vegetation (MCV/NVCS) Mapping Projects – California [ds515]. This dataset can help you discover what vegetation types are in your area of interest. California’s Natural Communities are based in the National Vegetation Classification System (NVCS), which is a hierarchical system; and VegCAMP works together with the California Native Plant Society (CNPS) to maintain California’s expression of the system. We publish a list of Natural Communities at the bottom two levels: alliance and association. We also work to rank these communities for rarity, using the same ranking concepts as are used for species in CNDDB. Our published Natural Community lists and other online information were also recently updated. For more information, please see VegCAMP's Natural Communities page (updated November 2019) and 
CNPS' Online Manual of California Vegetation (updated October 2019).
Where does ds515 come in? If you are working in an area and want to know what vegetation types have been documented there, you can see if there is a mapping project overlapping or near your area of interest. If you click on one of the polygons of ds515 in BIOS, you will see who is responsible for the map, whether it is complete, and how old it is. There are links in ds515 to download the datasets and view the classification and mapping reports. The classification reports have keys that will help you determine vegetation types based on species cover. Since many of the maps are produced at the alliance level, which is coarser than the association level, it is important to know how to identify associations. This is particularly true for those interested in determining whether there are sensitive natural communities present, because there can be sensitive associations within alliances that are broadly distributed that are not considered sensitive. To see ds515, along with other published vegetation datasets, including a newly published, updated map of the Delta (ds2855) and part of the Modoc Plateau (ds2858), please see our BIOS bookmark.