Influence of orchard management system on yield, quality and vegetative characteristics of apple trees.

Eight orchard management systems (central leader, minimum pruning, free standing pal- mette, palmette, Lincoln canopy, Tatura trellis, Ebro espalier and MIA) were compared over seven years (1982-1989) for their effect on fruit yield, quality and vegetative characteristics. A single rootstock (‘Northern Spy’) and two cultivars were used (‘Granny Smith’ and ‘Starking Delicious’). Each system was replicated at a number of planting densities. The experiment demonstrated that density was the major factor determining tree performance and in comparison, system or canopy shape had only minor effect. Higher yields at higher densities were associated with the higher per hectare trunk cross- sectional area. No evidence was found for changes in yield efficiency. The effect of system on leaf area index (LAI) was non-significant, suggesting a high degree of plasticity by the tree in response to changes in canopy geometry.