How to Manage Pests

UC Pest Management Guidelines

DESCRIPTION OF THE PEST

Brown mites can be recognized by their flattened bodies and long front legs. Adults are brownish green; nymphs are red at first. Brown mites overwinter as eggs on twigs and branches. Eggs hatch in spring and the young move out to leaves where they feed but do not produce webbing. Brown mites feed only during the cool parts of the day and migrate back to the spurs during midday.

DAMAGE

Brown mites feed by sucking the contents out of leaf cells. Such leaf damage reduces tree vitality and can adversely affect fruit size. Leaf injury caused by brown mites begins as a mottling and browning of leaves. Trees can tolerate low to moderate populations of brown mite, but heavy populations can remove almost all the chlorophyll from leaves and entire trees will take on a pale yellow appearance.

MANAGEMENT

Allowing low populations of brown mites in the orchard during spring enables mite predators to increase their population to levels that are more effective in controlling webspinning mites. Hot weather and predators cause brown mite populations to decline in summer. Treatment is not generally recommended.

Biological Control
Several predaceous species feed on brown mite, including lacewings (Chrysoperla spp., Chrysopa spp., and Hemerobius sp.), damsel bugs (Nabis sp.), lady beetles (Hippodamia convergens and Stethorus picipes), and minute pirate bug (Orius tristicolor).

Organically Acceptable Methods
Biological control and oil sprays during dormancy are organically acceptable methods of controlling brown mites.

Monitoring and Treatment Decisions
Evaluate mite populations when taking a DORMANT SPUR SAMPLE and record results on a monitoring form (100 KB, PDF).

PDF: You need a PDF reader, such as Acrobat Reader version 8 or later, to view or print this PDF. If no reader is installed on your computer, you can download a free copy of Adobe Acrobat Reader.

PUBLICATION

UC IPM Pest Management Guidelines: Prune
UC ANR Publication 3464
Insects and Mites
C. Pickel, UC IPM Program, Sutter/Yuba counties
F. J. A. Niederholzer, UC Cooperative Extension, Sutter/Yuba counties
W. H. Olson, UC Cooperative Extension, Butte County
F. G. Zalom, Entomology, UC Davis
R. P. Buchner, UC Cooperative Extension, Tehama County
W. H. Krueger, UC Cooperative Extension, Glenn County
Acknowledgment for contributions to Insects and Mites:
W. O. Reil, UC Cooperative Extension Solano/Yolo counties

Top of page