How to Manage Pests
UC Pest Management Guidelines
Brown wheat mite: Petrobia latens
Winter grain mite: Penthaleus major
Banks grass mite: Oligonychus pratensis
In this Guideline:
Mites are tiny arthropods that feed on the sap of host plants.
Because they are so small, use a hand lens to see them. They have 8 legs (6 in
the first stage). The brown wheat mite is about 0.025 inch long (0.635 mm), oval shaped and dark red or brown in
color. The winter grain mite is larger, 0.04 inch long (1 mm)and dark bluish black with red-orange legs
and a reddish patch on the upper side. Banks grass mite is extremely small,
0.001 inch (0.025 mm), and yellow to cream colored. It is the only prominent
wheat mite that webs the leaves.
Leaves injured by brown wheat mite first appear silvery and later
take on a scorched appearance. Injury caused by the winter grain mite results
in yellowish leaves and stunted plants. The damage caused by this mite is similar to winter-kill.
Banks grass mite turns leaves silvery and the tips and margins later turn
brown. Webbing is an additional sign that injury is caused by the Banks grass
mite. In California, mites seldom cause sufficient damage to be of concern.
wheat mite and Banks grass mite cause the greatest injury to water-stressed
grain. A timely irrigation will usually alleviate the problem. Crop rotation is
detrimental to the winter grain mite.
controls are not generally recommended as cultural techniques generally
suffice. Application of chemicals for aphid control may lead to a build-up of
mites, however, leading to the occasional need for an acaricide.
|When choosing a pesticide, consider
information relating to natural
enemies and honey bees
as well as the environmental impact.
||MODE OF ACTION GROUP NUMBER1: 1B
||COMMENTS: For use on wheat and triticale
only. Do not make more than 2 applications. Do not graze within 14 days.
Highly toxic to honey bees if bees are present at treatment time or within a day after.
UC IPM Pest Management Guidelines: Small Grains
UC ANR Publication 3466
Insects and Mites
C. G. Summers, Entomology, UC Davis/Kearney Agricultural Center, Parlier
L. D. Godfrey, Entomology, UC Davis
Acknowledgment for contributions to Insects and Mites:
D. Gonzalez, Entomology, UC Riverside
Top of page