European Red Mite

The European red mite is bright red and has a round body with white spots at the base of hairs on its back. The European red mite overwinters 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. During summer there are numerous overlapping generations, with eggs being laid on upper and lower surfaces of leaves during summer and on twigs or larger limbs in fall.

European red 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 European red mite begins as a mottling and browning of leaves. Unless populations are very heavy, European red mite does not cause defoliation.

Allowing low populations of European red 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 European red mite populations to decline in summer. Generally, treatment is not recommended.

Several predaceous species feed on European red 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). The western predatory mite, Metaseiulus (=Galendromus) occidentalis, also feeds on European red mite but is not as effective as it is on webspinning mites because of its inability to break through the egg shell of the European red mite.

Minimize the potential for mite problems by reducing dusty conditions in the orchard and by keeping the trees well irrigated.

Biological and cultural control and oil sprays during dormancy are organically acceptable methods of controlling European red mites.

Evaluate mite populations when taking a DORMANT SPUR SAMPLE . Record results on a monitoring form (PDF).