Abstract
Labor requirements for several orchard operations were monitored over three consecutive years with three orchard systems of Fuji trees grown on Marubakaido (Males prunifolia Borkh. var. ringo Asami) rootstocks. Orchard systems studied were; low-density system (9m×9m) with conventional open-center trees, medium-density system (6m×4m) with central leader trees, and high-density system (4m×2.5m) with central leader trees. Labor requirements were determined in terms of seconds perharvested fruit.
The low-density and medium-density systems did not differ significantly in labor requirements for hand pollination and harvesting. The medium-density system, however, was less labor-cosuming than the low-density system with regard to fruit thinning as well as leaf removing and fruit turning both practiced in the fall to improve red color development.
It was suggested that cutting-back of lateral branches lead to a remarkable reduction of labor requirements for hand pollination, fruit thinning, and harvest operations in the high-density system, otherwise comparable with those for the low-density system, the lowest of the three orchard systems. Labor efficiency on the per fruit basis for the above-mentioned operations was suggested to be improved with higher crop load of the trees.
No significant differences were detected in labor requirements on the 0.1ha basis for pruning operation among the three orchard systems.
Traveling times of air-blast sprayers were in the order of; medium-density system < low-density system ≈ high-density system.
