How to Manage Pests
UC Pest Management Guidelines
In this Guideline:
Cankerworm larvae have three pairs of prolegs. They are greenish
above, with three narrow, whitish stripes and one yellow stripe along the side
of the body; underparts are light green. Cankerworms frequently stand on the posterior pair of prolegs in such a way that they resemble a small twig.
Fall cankerworms pass the winter in the egg stage. Fall caterpillars hatch and
feed on leaves in spring and summer, then pupate and develop into moths in
fall. There is one generation per year.
The larvae are primarily leaf feeders, tending to skeletonize
leaves. Occasionally they feed on young fruit by biting deep holes, which later
heal, but leave large scarred depressions similar to the injury caused by green
Insecticide sprays applied for other pests often keep these
leaf-eating caterpillars in check.
trees, cut out and destroy infested twigs.
Organically Acceptable Methods
control and Bacillus thuringiensis (Bt) sprays are acceptable for
use on organically certified produce.
postbloom treatments of Bacillus thuringiensis will control this
pest when larvae are present. The Bt program used for peach twig borer control
reduces cankerworm damage.
||Amount to Use**
|When choosing a pesticide, consider information
relating to impact on natural enemies and honey bees, impact of timing on beneficials, and environmental impact Not all registered pesticides are listed. Always read label of product being used.
|BLOOM and POSTBLOOM
||BACILLUS THURINGIENSIS ssp. KURSTAKI#
||MODE OF ACTION GROUP NUMBER1: 11.B2
||COMMENTS: Most effective on small caterpillars. Does not destroy natural enemies.
UC IPM Pest Management Guidelines: Plum
UC ANR Publication 3462
Insects and Mites
W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
K. R. Day, UC Cooperative Extension, Tulare County
Acknowledgment for contributions to Insects and Mites:
R. E. Rice, Kearney Agricultural Center, Parlier
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