Plum, Prune (Fresh): Spider mites

categories: Plum, Prune (fresh) Plum, Prune (Fresh) Insects Tree Fruits

revision date: 2022-12-05 12:00

Spider mites under microscope.
Spider mites under microscope
Photo by: L.K. Tanigoshi

Biology

Several species of spider mites can be found on plums. They range in color from pale yellowish or green to red or brown. Spider mites feed on the leaves (typically on the underside), causing a whitish, yellow, or brown stippling. More severe damage to leaves results in a bronzed appearance. Heavy infestations may cause leaf drop. Spider mite feeding is usually accompanied by webbing on leaves and between leaves and twigs, although the European red mite produces smaller amounts of webbing than other species. Spider mite infestations are worse in hot, dry, dusty conditions.

Management Options

Use Integrated Pest Management (IPM) for successful plant problem management.

Non-chemical Management

Select non-chemical management options as your first choice!

  • Provide proper culture. Healthy plants are more tolerant of damage, while drought-stressed plants are more susceptible.
  • Predatory mites and insects such as ladybird beetles and green lacewings aid in control of mite populations. Avoid use of broad-spectrum insecticides which kill beneficials.
  • Hose mites from plants with a strong stream of water.
  • High levels of nitrogen in the foliage encourage spider mite reproduction. Switch to a slow-release or low-nitrogen fertilizer.

Chemical Management

IMPORTANT: Visit Home and Garden Fact Sheets for more information on using pesticides.

  • Apply as soon as mites are present.
  • Avoid applying when blossoms are present.
  • Soaps may require several applications.
  • Homeowners should not make foliar applications to trees over 10 ft tall.
  • Consult a commercial pesticide applicator for treatment of trees and shrubs over 10 ft. tall.

Approved Pesticides

Listed below are examples of pesticides that are legal in Washington. Always read and follow all label directions.

Additional Images