Experimental miticides on European red and Pacific mites

Leaf-feeding mites are one of the most J severe pest problems for growers of deciduous fruits and nuts in California. The mites primarily responsible for these problems include the European red mite, Panonychus ulmi (Koch), the two-spotted mite, Tetranychus urticae Koch, and the Pacific mite, T. pacificus McGregor. Control of these and other species of mite pests has depended upon the use of pesticides that may be harmful to non-target species of insects and mites, and may also lose their efficacy against target species because of a build-up of resistance. In an attempt to find those materials that are effective against the target species, and the least harmful to non-target species, new chemicals are continually being evaluated for their effect on both pest and beneficial species of mites and insects. This report presents the results of field trials of new, but as yet unregistered, pesticides that were evaluated as miticides on the European red mite and Pacific mite during 1971.