Phytophthora ramorum (Sudden Oak Death Infestation Areas in California)

This dataset represents an approximate index of sudden oak death (Phytophthora ramorum) infestation based on the amount of area in 1/4 mile buffer around all confirmations (as of 6/5/2008) that is contained within roughly 1,067 hectare hexagons. Infestations are confirmed by pathologists from U.C. Davis, U.C. Berkeley, and California Department of Forestry. This dataset likely underestimates the real amount of sudden oak death present in California because the underlying data represent only confirmed samples (not all areas have been sampled).

The data used to create this dataset were obtained by the Conservation Biology Institute (CBI) from the Sudden Oak Death Project (Geospatial Imaging and Informatics Facility) at U.C. Berkeley on 7/23/2008. The original data represented 1/4 mile buffers around confirmed occurrences of sudden oak death. CBI intersected this dataset with an equal-area hexagon system produced using the DGGRID software (http://www.sou.edu/cs/sahr/dgg/dggrid/dggrid.html) by Kevin Sahr. Level 14 in the hexagon system was used for this analysis. Hexagons are roughly 1,067 hectares in size. CBI calculated the amount of area in the 1/4 mile buffers around sudden oak death confirmations within each hexagon cell as a percentage.