Spray chemical deposits in high-density and trellis apple orchards

Chemicals deposited on foliage varied by a factor of three to five times when sprays were applied with an airblast sprayer to apple (Malus domestica Borkh.) trees in various training systems. Deposits were higher with vertical than horizontal training systems, smaller tree sizes, and less-dense tree canopies of spur-type trees. The Lincoln canopy tree training system prevented good spray penetration because the airblast spray pattern was split by the horizontal nature of the canopy