How to Manage Pests

UC Pest Management Guidelines


Harvest Fruit Sample

(Reviewed 11/12 , updated 11/12 )

In this Guideline:

At harvest, take a fruit sample from the bins to assess the effectiveness of the current year's IPM program and determine the needs of next year's program. Look for insects or damage, and try to determine what pest may have caused the damage.

Record your observations (example form PDF)


Examine 200 fruits per bin from 5 bins per orchard (or 20-acre block in larger orchards) for a total of 1,000 fruit for insect or disease damage.

Look for the presence of

  • Stings or deep entries: an indication of codling moth
  • Superficial feeding on skin: an indication of obliquebanded leafroller larvae (summer generation)
  • Black sooty mold: an indication of:
  • Russeting: an indication of
    • Pearleaf blister mite (Oval, convex spots less than 0.5 inch in diameter with a surrounding halo of clear tissue; spots frequently run together, leaving fruit deformed and misshapen.)
    • Pear rust mite (Uniform areas of russeting localized in stem end or calyx)
    • Western flower thrips (Pockmarked areas of russeting and shallow scabbing)
  • Deep depressions: indication of
    • Western boxelder bug (Depressions with white pithy areas under skin)
    • Consperse stink bug (Depressions concentrated near stem end; white pithy areas in fruit under depression; may be confused with boxelder bug)
    • Lygus bug (Similar to stink bug but feeding areas can have an open pustule; hard cells located in fruit under pustule).
  • Misshapen fruit: an indication of early season caterpillar damage caused by obliquebanded leafrollers and miscellaneous caterpillars (green fruitworm, fruittree leafroller)
  • Bumpy fruit: San Jose scale (Red halos may be present around scale.)
  • Other types of damage:
    • Katydids (Small [0.2 inch], deep bite marks)
    • Mealybugs (May be present in calyx end)
  • Scabby areas on fruit surface: an indication of pear scab (Fruit may also be misshapen.)



[UC Peer Reviewed]

UC IPM Pest Management Guidelines: Pear
UC ANR Publication 3455

General Information

L. G. Varela (Crop Team Leader), UC IPM Program, UC Cooperative Extension Sonoma County
R. B. Elkins, UC Cooperative Extension Lake County
R. A. Van Steenwyk, Insect Biology, UC Berkeley
C. Ingels, UC Cooperative Extension Sacramento County
L. R. Wunderlich, UC Cooperative Extension El Dorado County

Top of page

PDF: To display a PDF document, you may need to use a PDF reader.

Statewide IPM Program, Agriculture and Natural Resources, University of California
All contents copyright © 2017 The Regents of the University of California. All rights reserved.

For noncommercial purposes only, any Web site may link directly to this page. FOR ALL OTHER USES or more information, read Legal Notices. Unfortunately, we cannot provide individual solutions to specific pest problems. See our Home page, or in the U.S., contact your local Cooperative Extension office for assistance.

Agriculture and Natural Resources, University of California

Accessibility   Contact webmaster.