California (statewide) map of officially confirmed wildland confirmations of Phytophthora ramorum through December 2017

Map of confirmed counties with Sudden Oak Death caused by Phytophthora ramorum in Northern California

Note that the maps provide a general idea of pathogen distribution in wildlands but not every record is displayed.

SODMAP includes P. ramorum reports confirmed by an official laboratory, including negative findings, with the intention of sharing known distribution information gathered by public agencies and research groups across the country.

The Oakmapper site provided a GIS tool which allowed users to learn about P. ramorum distribution in California. The online site was taken down in fall 2017 but the data files are available for download and use in your own GIS program. Download a zip file that contains the Officially Confirmed and Community Submitted shapefiles here.

Risk Maps

Video of projected Phytophthora ramorum spread in California from  Meentemeyer, R. K.; Cunniffe, N. J.; Cook, A.R.; Filipe, J.A. and others. 2011. Epidemiological modeling of invasion in heterogeneous landscapes: spread of sudden oak death in California (1990–2030). Ecosphere. 2(2): 1-24.

National SOD Risk Map: Koch, F.H.; Smith, W.D. 2012. A revised sudden oak death risk map to facilitate national surveys. Chapter 7 in Potter, K.M.; Conkling, B.L. (eds.) Forest Health Monitoring 2009 National Technical Report. Gen. Tech. Rep. SRS-167. Asheville, NC: U.S. Department of Agriculture, Forest Service, Southern Research Station, pp. 109-136.

US East Coast Hazard Map: Establishment of Phytophthora ramorum in the Appalachian Mountains would pose the greatest threat to vegetation in the Eastern U.S., according to a Hazard map developed by modelers out of Chris Gilligan’s lab at Cambridge University.

More about this and other epidemiological modeling work from the Gilligan group may be found at by emailing Dr Matt Castle (

[Additional risk maps can be found on the Modeling the Distribution and Spread of P. ramorum page]

USDA Forest Service, State and Private Forestry-Pacific Southwest Region Aerial Detection Survey: View the latest tree mortality maps generated by aerial flyovers.