Effect of Canopy Density on Pesticide Deposition and Distribution in Apple Trees. J. W. Travis, Department of Plant Pathology and Horticultural Science, North Carolina State University, Raleigh 27695. W. A. Skroch, and T. B. Sutton. Department of Horticultural Science, and Department of Plant Pathology, North Carolina State University, Raleigh 27695. Plant Dis. 71:613-615. Accepted for publication 28 January 1987. Copyright 1987 The American Phytopathological Society. DOI: 10.1094/PD-71-0613.

Medium and small Golden Delicious apple trees were pruned to high, moderate, and light canopy densities. Four metal chelates (Sequestrene Zinc, Sequestrene Copper, Sequestrene Manganese, and Sequestrene 330 Fe) were applied to each of the trees with an airblast orchard sprayer. The leaf deposits were analyzed by foliar mineral analysis. The highest mean deposition and lowest variation in deposit were observed on the trees with light canopy density. Deposits on trees with high and moderate canopy densities were not different, but deposit variance was greater on trees with high canopy densities.