How to Manage Pests
UC Pest Management Guidelines
Peach Silver Mite
Scientific Name: Aculus cornutus
(Reviewed 6/10, updated 6/10, pesticides updated 9/15)
In this Guideline:
Description of the Pest
Peach silver mites are tiny, four-legged eriophyid mites, yellow to pinkish white, and somewhat wedge shaped, being broadest just behind the anterior end. Because they are so tiny, they are difficult to see without a hand lens of at least 10x power.
Peach silver mites overwinter as females in bark crevices, around buds, and under bud scales. They move to leaves soon after budbreak in spring. These mites can also be found on small fruit, often inhabiting the area between the calyx and the fruit. Later in the season they are found primarily on the lower leaf surface. Before leaf fall, females move to overwintering sites. Many generations are produced during the season.
On rare occasions when very high populations of peach silver mite survive the winter, they produce symptoms on the unfolding leaves. Symptoms consist of minute, yellow spots and a tendency for the leaf edges to curl toward the midrib. Ordinarily, however, most injury is not noticed until mid- to late summer when heavily infested leaves take on a silvery appearance.
Treatments applied specifically for control of peach silver mite are rarely needed and should be avoided because peach silver mites serve as early season food for predaceous mites, which in turn aid in reducing populations of other pest mites. The use of broad-spectrum insecticides for other pests can cause high infestations of peach silver mite.
Organically Acceptable Methods
Sulfur sprays are acceptable for organically certified crops, but will reduce predator mite populations.
Monitoring and Treatment Decisions
If heavy populations (200–300 per leaf) of peach silver mite are present and causing damage, consider applying sulfur or miticides used for control of other mite species. Some insecticides applied for control of other pests eliminate peach silver mites as well.
UC IPM Pest Management Guidelines: Nectarine
Insects and Mites
K. R. Day, UC Cooperative Extension, Tulare County
Acknowledgment for contributions to Insects and Mites:W. J. Bentley, UC IPM Program, Kearney Agricultural Center, Parlier
R. E. Rice, Kearney Agricultural Center, Parlier