Ceratocystis canker disease in stone fruit orchards can be prevented or controlled by wise use of mechanical harvesting equipment and by canker surgery. A new mercurial wound dressing developed by University of California researchers has been registered by the USDA for use on bark wounds of almond and prune trees. Recent discoveries concerning the associations between various insects and the fungus, Ceratocystis fimbriata, have helped to explain not only the rapid spread of this disease in orchards, but also the role of soil moisture in its development.

Extension Plant Pathologist H. J. O'Reilly and Graduate Student Steve Sinden, U. C., Davis; and Farm Advisors Art Retan and Clem Meith, Butte County; Roy Jeter, Glenn County; Don Rough, San Joaquin County; Dave Chaney, Sutter County; and Dave Holmberg, Yolo County, assisted in this research. Cerano is a trade name of the John Taylor Fertilizer Co., Sacramento.