Integration of Insect and Mite Management With Disease and Weed Control in Pecan Production

Pecan orchards in the southeastern US are managed to conserve resources, protect the fruit and foliage from injury caused by phytophagous insects, mites, and pecan scab, and remove competition from weeds during the establishment of newly planted trees and in the preparation of the orchard floor as a harvesting surface. Costs associated with pest control are significant each year and the growers use integrated pest management methods to increase the effectiveness of pesticide treatments and reduce control costs. A coordinated research and extension effort over the past 25 years in entomology, plant pathology, weed science and horticulture has reduced the amount of pesticide use by 35%. Four advances have been responsible for the reduction. First, pecan scab sprays are reduced by linking the frequency of applications to the climatic conditions and the cultivar susceptibiltiy. Second, pest-specific insecticides that are toxic to the pests and not toxic to beneficial insects and mites are used to control lepidopterous pests and conserve aphidophagous insects and mite predators. Third, cover crops have been developed to supplement the soil with nitrogen and organic matter and conserve beneficial insects. Fourth, weed studies have led to the elimination of weeds in the first 8 years after planting around young trees, chemical mowing methods in established orchards and selective grass control to increase the growth of clover cover crops. The development and implementation of these and other significant advances in pecan management are reviewed in this chapter.