Biological Control Best Practices
Biological control — releasing the natural enemies of pests — can be an effective means of integrated pest management if done correctly. Following are biocontrol best practices as recommended in a recent blog post by Ben Faber.
First, it’s important to recognize that conserving the natural enemies of pests in your grove (rather than purchasing natural enemies) is the most effective — and cost-effective — means of pest management. Second, it’s important to recognize that biocontrol methods will not be effective in desperate situations where pests or their damage is widespread. Growers must be proactive, monitor their groves for pests and release natural enemies before pests are too abundant.
Before purchasing natural enemies, it’s important to first correctly identify the pest, learn about its biology (such as vulnerable stages of its life cycle), correctly identify its natural enemies and consult the University of California (UC) IPM Pest Management Guidelines to determine whether the release of a particular natural enemy has been demonstrated to be effective in California.
Once you have settled upon the release of a particular natural enemy, be certain to determine which life stage of the species is appropriate for release and whether the biocontrol should be released by inoculation or inundation. Inoculation is the release of a few natural enemies whose offspring are used for biological control. Inundation is the release of large numbers of the natural enemy, with the released enemy and their offspring providing biological control. It’s also important to release the natural enemies when the pests are at a vulnerable life stage and are present in numbers that can be controlled by the release.
Before purchasing natural enemies, be advised that it is illegal to obtain insects and other arthropods from outside the state of California (they cannot be carried or shipped across state lines) without a permit from agricultural officials. Producers and suppliers of natural enemies who are members of the Association of Natural Biocontrol Producers all formally agree to a code of ethics and standardized methods.
When releasing the natural enemies, protect them from extreme conditions and release them in the evening or early morning during hot weather. After the natural enemies have been released, avoid applying broad-spectrum residual insecticides (also avoid such application just prior to release) and be certain to provide the natural enemies with appropriate food, shelter and water.
For more information, consult the UC IPM Pest Management Guidelines.