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Low-volume airblast sprayers have been used for pest control in Okanagan Valley orchards for the last 25 yr. While many significant improvements have been made in sprayer design during this period, the basic form of the machines has remained the same. Characteristically the blower unit is mounted close to the ground and the spray-laden airstream is directed up through the trees. While these units give good pest control they do not distribute the pesticide uniformly but consistently apply more to the lower parts of the trees than to the upper parts (1, 5). Also, if the airstream is strong enough to carry the spray to the tops of the trees, inevitably some spray material is lost to the atmosphere above the trees. For years we have been concerned about the inefficient use of pesticide resulting from this non-uniform distribution, and about the atmospheric pollution caused by spray drift. We felt that the logical way to improve distribution was to use a
a tower sprayer for tree-wall plantings
McMechan, A.D. and A.P. Gaunce 1975. A TOWER SPRAYER FOR TREE-WALL PLANTINGS. Canadian Agricultural Engineering 17(1):31-33.
31 - 33