The vegetation map was created in ARCGIS using an orthophoto base layer from the National Agricultural Imagery Program (NAIP) with the Canada de los Osos Ecological Preserve boundary as an overlay. The original database derived for the purpose of creating a vegetation map for CDLO contained an appreciable level of detail and consequent large number of classifications that were not suitable for the mapping process. Therefore, all subsets of a classification were grouped into a single classification while retaining the vegetation labels defined by the Wildlife and Habitat Branch. For example, while there may have initially been four or five different types of Umbellularia californica '' Quercus agrifolia habitat based on percent cover, height and DBH classes etc., there is now only one type of Umbellularia californica '' Quercus agrifolia habitat based on dominant species indicated on the map.Furthermore, all of the features used to delineate a given subset of the original classification scheme do not apply to the modified classifications used to create the map. As a result, the original database was retained and a copy of that was modified and saved. The modified database was used as an attributes table for the vegetation shape files in the map.Mapping consisted of creating vegetation polygons on the NAIP layer within ARCGIS. Vegetation at the Alliance level is generally more easily mapped by aerial photo than that described at the Association level. Therefore, it was necessary to ground-truth for purposes of quality control.Certain “mapping rules” were created to maintain consistency when creating polygons.Trees separated from a larger, woodland stand by greater than two times their canopy width were not included within the larger stand.Similarly, grassland polygons can contain trees that do not appear associated with an adjacent woodland polygon.Trees within grassland forming an apparent savannah community were mapped as a community separate from the extenuating grassland. If members of that community appeared to merge with adjacent woodland, they were retained in the savannah polygon.Areas of grassland or scrubland surrounded by woodland and less than five meters in width were incorporated into the woodland polygon.The map was prepared for publication in BIOS by the California Department of Fish and Wildlife Vegetation Classification and Mapping Program.