How to Manage Pests

UC Pest Management Guidelines

Monitoring is a crucial component of all IPM Programs. It helps you identify potential problems and to assess the overall condition of the orchard. Check the orchard regularly for pests and natural enemies of pest species, as well as the maturity and health of the crop.

There are six major monitoring periods in an apple orchard. The presence and population development of key pests are tracked during these periods. The information below outlines the monitoring periods, major pests monitored, and the methods used to monitor them. Detailed information on each pest and its monitoring method is available under the individual pest sections in this guideline.

• Look for mite eggs, rosy apple and green apple aphid eggs, San Jose scale

• Prebloom (Green tip to pink bud)
• Examine shoots for rosy apple and green apple aphids and caterpillars (apple pandemis, fruittree leafroller, green fruitworms, obliquebanded leafroller, omnivorous leafroller, orange tortrix)
• Monitor weather for conditions favorable to scab, powdery mildew, bacterial blast
• Bloom (First bloom to petal fall)
• Monitor weather for conditions favorable to scab, fireblight, bacterial blast, powdery
  mildew
• Set out and monitor codling moth traps by mid-March
• In mating disruption orchards, put pheromone dispensers out
• Continue to examine shoots and bloom for aphids and caterpillars (apple pandemis, fruittree leafroller, green fruitworms, obliquebanded leafroller, omnivorous leafroller, orange tortrix)
• Postbloom
• Continue monitoring weather for conditions favorable to scab, fire blight, powdery
  mildew
• Continue monitoring codling moth trap and check fruit
• Continue to examine shoots and leaves for rosy apple and green apple aphids, leafhopper nymphs, leafrolling caterpillars (apple pandemis, fruittree leafroller, green fruitworms, obliquebanded leafroller, omnivorous leafroller, orange tortrix), tentiform leafminer and parasitism (April and May), and San Jose scale crawlers (May)
• Monitor weeds for stink bugs and fruit for lygus bug damage

• Continue monitoring codling moth traps and check fruit
• In mating disruption orchards, apply a second application of pheromone when first
  expires
• Examine fruit for orange tortrix (June-July), pandemis (June-July), obliquebanded leafroller (July–August), eyespotted bud moth (June-July), and stink bug/lygus damage
• Examine leaves for mites, tentiform leafminer (June), leafhoppers

• Preharvest
• Continue monitoring codling moth traps and check fruit
• Examine fruit for lygus/stink bug damage
• Examine leaves for mites and leafhoppers

PUBLICATION

UC IPM Pest Management Guidelines: Apple
UC ANR Publication 3432
General Information
J. L. Caprile, UC Cooperative Extension, Contra Costa County
L. R. Wunderlich, UC Cooperative Extension, El Dorado County
P. M. Vossen, UC Cooperative Extension, Sonoma and Marin counties
W. W. Coates, UC Cooperative Extension, San Benito County
H. L. Andris, UC Cooperative Extension, Fresno County
L. G. Varela, UC IPM Program, Sonoma County
W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
Acknowledgment for contributions to the insects and mites section:
C. Pickel, UC IPM Program, Sutter and Yuba counties

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