AIRBLAST SPRAY PARTITIONING IN A MATURE PECAN ORCHARD

摘要

Spray applications of Malathion were made with a radial airblast sprayer in an 11 m tall, mature pecan orchard, in the Middle Rio Grande valley of New Mexico. Measurements of drop size distributions from the sprayer were made with an imaging laser drop size measurement system. Sprayer effectiveness in penetration of the tree canopy was examined by sampling a vertical profile of droplet sizes on the opposite side of the row from the application. Spray volume samples were collected with continuous string samples arranged on a cross-row rectangle frame encompassing two tree rows. The first tree row reduced the overall D _v0.5 by a factor of 7. The measurements indicated that, overall, 4.5% of the total mass sprayed went out the top of the canopy; 22.2% was deposited on the ground between and beneath the adjacent tree rows; 12.2% passed through the left side tree row; and 4.0% passed through the right side tree row. The remainder, 57.1% of the material, was assumed captured by the adjacent tree rows