Mature ‘Golden Delicious7M.9 apple trees were: 1) mechanically root pruned on two sides 50 cm from the trunk to a depth of 40 cm; 2) deblossomed by hand; 3) both root pruned and deblossomed; or 4) untreated. The treatments were applied annually for four years at full bloom. Root pruning reduced trunk cross-sectional area, shoot length, shoot number to spur number ratio, shoot leaf size, and shoot leaf area to spur leaf area ratio in cropping apple trees. The effects were much less on the vegetative growth of deblossomed trees. Root regeneration was abundant in root pruned plus deblossomed trees, but low in cropping trees. Compared with unpruned control trees, root pruned trees had more negative leaf water potential, reduced stomatal conductance, and reduced transpiration, while deblossomed trees had less negative leaf water potential, lower net photosynthesis, stomatal conductance and transpiration. Leaves of root pruned plus deblossomed trees had intermediate rates of net photosynthesis. Mid-terminal sho...