Phytophthora ramorum early detection surveys for forests in the United States, 2003-2006This article is part of a larger document. View the larger document here.
Risk-based early detection surveys in U.S. forests were conducted between 2003 and 2006 using 100 m vegetation transects. Thirty-nine states surveyed 3,570 locations in states with endemic Phytophthora ramorum; states where the pathogen had been confirmed only in woody ornamental nurseries; and states that had received potentially infected stock but did not confirm the pathogen. A total of 12,699 samples from 44 host and associated host genera were collected and diagnosed for the pathogen using nested or real-time PCR. Phytophthora ramorum positive diagnoses were obtained for two samples from San Francisco County, California confirming that the pathogen is not yet idely established outside the regulated areas on the west coast.