If you are experiencing problems downloading PDF or HTML fulltext, our helpdesk recommend clearing your browser cache and trying again. If you need help in clearing your cache, please click here . Still need help? Email firstname.lastname@example.org
Reported here are dispersion statistics associated with a beating-tray method of sampling and sequential sampling procedures which optimize time spent estimating adult pear psylla densities. Psylla pyricola Foerster adults do not form cohesive groups or colonies such as aphids, but they do show a definite contagious distribution. Beating-tray samples taken during the early growing season, before foliage had developed, were slightly more variable, suggesting they were less efficient in estimating density than those taken after foliage developed. Insecticide applications did not affect the dispersion of pear psylla adults. Calculated stop lines for estimating adult pear psylla densities within 50% of the mean indicate minimum samples of 5, 8, and 12 trays at error levels of P = 0.2, 0.1, and 0.05.
Document Type: Research Article
Publication date: June 1, 1981
More about this publication?
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.