ESTIMATION OF EGG POPULATIONS OF THE CLOVER ROOT CURCULIO, SITONA HISPIDULA (COLEOPTERA: CURCULIONIDAE), IN KENTUCKY ALFALFA AND RED CLOVER FIELDS,

Abstract

AbstractSampling techniques for estimating egg populations of the clover root curculio, Sitona hispidula (F.), were developed in alfalfa and red clover fields in Kentucky. An appropriate sample unit was a 3 × 3 in. (7.6 × 7.6 cm) area of plants and the soil beneath it to a depth of 4–5 in. (10.2–12.7 cm). This was processed by a flotation technique. The spatial disposition of the eggs conformed to a clumped pattern in both fields. The variation of 88 to 93% in log variances was accounted for by the variation in log means. There were no significant differences in dispersion pattern between the two crops. Variance analysis revealed that block and plot differences were rarely significant but the interquadrat variance predominated. The number of samples required to estimate the population with specified level of significance and margin of error was inversely proportional to population density.