Category Soilborne Diseases Subject Avocado Root Rot (Phytophthora cinnamomi) Title Avocado Root Rot (Phytophthora cinnamomi); visual symptoms Description Final stage symptoms of avocado root rot (Phytophthora cinnamomi). Stage 5 (nearly dead) of G. Zentmyer rating scale. Butcher Ranch, Montecito, CA. Location Montecito, CA Date May, 1962 Source George E. Goodall Larger Picture 1000 x 668 (106 kb)