When conditions are favorable during cold, wet weather during bloom, bacterial canker and blast can be devastating to say the least! Jim Adaskaveg with UC Riverside describes the conditions below that lead to it.

According to Dr. Adaskaveg, UC Pest Management Guidelines:

Symptoms are most obvious in spring, and include limb dieback with rough cankers and amber-colored gum. There may also be leaf spot and blast of young flowers and shoots. The sour sap phase of bacterial canker may not show gum and cankers, but the inner bark is brown, fermented, and sour smelling. Flecks and pockets of bacterial invasion in bark occur outside canker margins. Frequently, trees sucker from near ground level; cankers do not extend below ground.

In a recent research trial Evaluation of Antibacterial Treatments for Protection of cv. Coral Cherry Fruit from Bacterial Blast, Dr. Adaskaveg evaluated a variety of antibiotics and Magna-Bon CS 2005. Applications were done on 3-11-14 at 50% bloom using an air-blast backpack sprayer at a rate of 100 gal/A. Inoculated with copper-resistant strain fruit were evaluated for the presence of blast symptoms in mid-April.

Here are the results… (Click Picture for Full Image)

Magna-Bon CS 2005 had a 98% control of Bacterial Blast!

Recommended Application Rates according to label are:

  • Instructions: Make first application before fall rains and a second at late dormant. Use the higher rates when conditions favor disease. If needed, agricultural-type spray oil
    may be added. Where disease is severe, an additional application shortly after harvest may be required.
  • Rate per Acre per 100 gal. of water ppm’s: 32 – 64 oz
  • PPM’s (copper) per 100 gal.of water: 200 – 250 PPM

However, Jeff Alicandro also provides some insight into combating disease in cherries with copper…

Sweet cherry bacterial canker suppression can be achieved with dormant copper fungicide applications. Split copper applications, both in the fall and early spring- often work best for bacterial canker suppression. Like bacterial spot on peaches, in challenging seasons bacterial canker is not at all easy to control on highly susceptible sweet cherry cultivars.

Simply put, save your cherry orchards from disease…. use CS 2005!


“UC IPM Pest Management Guidelines: Cherry.” UC IPM Statewide Integrated Pest Management Program, Sept. 2015, ipm.ucanr.edu/PMG/r105101511.html.