Two well replicated field experiments on the effects of mite infestation were conducted in almond orchards in the southern San Joaquin Valley of California. The orchards were previously protected with acaricides from infestation by Tetranyshus spp. and citrus red mite, Panonychus citri (McGregor). The severe mite infestations which develop on almond in this area are not related to use of insecticides. replicated comparisons were made in both experiments by comparing growth and productivity of protected and unprotected trees. High mite populations that developed in summer did not adversely affect almond tree growth and productivity during the year in which the infestations occured. However, in the year following infestation, yields of unprotected trees were an ave 13% lower (P=0.05) in an orchard then in its 6th yr and 19% less (P=0.05) in an orchard then in its 4th yr, as compared with yields of trees protected with an acaricide. Similarly, in the year following infestation, length of terminals on unprotected trees was reduced 11% in the orchard in its 6th yr (not significant) and 48% (P=0.01) in the orchard in its 4th yr. Trunk growth of unprotected trees was reduced an avg 19% (P=0.05) in the year following mite attack, the 6th season of growth in the orchard.
Document Type: Research Article
Publication date: June 1, 1978
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Journal of Economic Entomology is published bimonthly in February, April, June, August, October, and December. The journal publishes articles on the economic significance of insects and is divided into the following sections: apiculture & social insects; arthropods in relation to plant disease; forum; insecticide resistance and resistance management; ecotoxicology; biological and microbial control; ecology and behavior; sampling and biostatistics; household and structural insects; medical entomology; molecular entomology; veterinary entomology; forest entomology; horticultural entomology; field and forage crops, and small grains; stored-product; commodity treatment and quarantine entomology; and plant resistance. In addition to research papers, Journal of Economic Entomology publishes Letters to the Editor, interpretive articles in a Forum section, Short Communications, Rapid Communications, and Book Reviews.