AbstractTotal deposits and their distribution on bush and dwarf hedgerow apple trees, sprayed at the late dormant and full foliage stages with a copper fungicide by five different methods, were estimated by colorimetric determination of the acid‐extracted copper from all the tree parts, and for comparison purposes were converted to equivalent volumes retained. The bush trees were sprayed by hand lance (4500 litresha‐1), by automatic nozzle mast sprayer (2250 litres ha−1), by conventional air‐blast sprayer at medium volume (1125 litres ha−1) and low volume (560 litres ha−1), and by hand‐directed ultra‐low‐volume (ULVH) fan‐assisted spinning‐disc sprayer (6 litres ha−1). The hedgerow trees were sprayed by conventional air‐blast sprayer at low volume (560 litres ha−1) and by an experimental tractor‐mounted ultra‐low‐volume air‐blast sprayer (45 litres ha−1). At the late dormant stage, the bush trees retained only 9–22 of the total spray applied by all methods, except that those sprayed by the hand‐directed ULVH sprayer retained 57. At the full foliage stage, when most of the spray was deposited on the leaves, retention for all methods of application was 22–37. The hedgerow trees at late dormancy retained 6 of the spray applied in low volume and 10 of that by tractor‐mounted ultra‐low‐volume methods, but at full foliage, retention was 25 and 63 , respectively. On both types of tree the proportions of the spray deposited on the tree components were
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