A vegetation map is a pictorial representation of the plant communities covering a given area of land. Groups of plant species that commonly occur together are delineated in a patch-like configuration on a map. These maps, with layers of detail such as species composition or soil type, become useful tools in understanding interactions between the biological and the physical world. Vegetation maps illuminate biological trends, such as an exotic weed taking over a native ecosystem, or the regrowth of vegetation after fire. Vegetation maps can also indicate the type of habitat where given rare plants or animals might be found, such as Pinnacles buckwheat (Eriogonum nortonii) or the San Joaquin coachwhip snake (Masticophis flagellum ruddocki). In addition to correlating the species with the habitat type, the map can reveal relationships that underlie the correlation, answering the question of why the given species is found in the habitat, or what specific characteristic of the habitat is associated with the species. For instance, in mapping valley oaks (Quercus lobata), the location of the oaks is consistently associated with fine soils on a geomorphic landform known as a Pleistocene Terrace. Information of this kind is vital for responsible management of the resources in our parks. Now, due to a national emphasis on Inventory and Monitoring within the National Park Service, Pinnacles National Park is carrying out a two-year Vegetation Mapping Project.