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Eighteen-year-old, top-dominant central leader trees of 'Granny Smith' apple (Malus domestica Borkh.) were restructured during the 1987 and 1988 dormant seasons into either palmette central leader (initially) or pyramid central leader forms. In the palmette form, pruning was restricted to the total removal of the uppermost east-and westfacing fruiting scaffolds in 1987, and the shortening of all middle scaffolds and the upper north-facing scaffold in 1988. In the pyramid form, major scaffold limbs were subjectively removed or shortened to reestablish the desired pyramid shape over the two H94049 Received 3 August 1994; accepted 8 May 1995 dormant seasons. Both forms were also renewal pruned annually to totally remove pendant fruiting laterals and spur-bearing wood over 4 years old. In addition, unmodified top-dominant trees that were either renewal pruned or containment pruned (primarily heading cuts) were maintained for comparison with the restructuring treatments. The restructuring treatments resulted in improved light penetration to the lower and inner canopy regions, improved spur quality, and in a greater proportion (50% cf. 30%) of the fruit being borne in the lower half of the tree. Cumulative yield over the 3 years of study was not reduced in the restructured trees in comparison with the containment-pruned topdominant trees and was reduced by only 20% in comparison with the renewal-pruned top-dominant trees. Mean fruit size in both the upper and lower tree regions was not altered by the restructuring treatments. Renewal pruning alone compared with containment pruning resulted in a total yield gain of 28% and an 8% increase of mean fruit size in the lower canopy but did not lead to a redistribution of fruit within the tree. Major upper canopy restructuring combined with annual renewal pruning, therefore, achieved the greatest gains in both yield, and fruit size along with improved fruit distribution within the tree.