How to Manage Pests

Pests in Gardens and Landscapes

Brown rot—Phytophthora spp.

Ripe or ripening citrus fruit on the lower part of the tree may develop a light brown, water-soaked decay often called brown rot. Affected fruit develop a pungent odor. Fruit in the early stage of the disease may go unnoticed at harvest and infect other fruit during storage.


Remove diseased fruit. Do not store infected fruit with clean fruit. Prune tree skirts so branches are at least 2 feet from the ground. A preventive Bordeaux treatment applied before first fall rains can be applied to tree skirts up to 4 feet and the ground beneath trees.

Early stages
Early stages of brown rot on oranges

Infestation of brown rot
Infestation of brown rot on lemons

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2017 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   Contact webmaster.