Submitted to: American Society for Horticultural Science
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: January 19, 1996
Publication Date: N/A
Interpretive Summary: Excessive shoot growth in peach trees limits fruit yield by shading the interior of the tree thus reducing fruit bud initiation, directly competing with growing fruit, and increasing the cost of production through high labor costs for pruning. Dwarfing rootstocks have not been developed for peaches at this time and cultural techniques to control tree growth are either too expensive or inconsistent in their response. We wanted to determine if we could reduce shoot growth by growing peach trees in vegetation-free areas (VFA) of different sizes surrounded by a grass sod. We found that the size of the tree and its fruit yield were proportional to the size of the VFA; the larger the VFA, the larger the tree and yield. However, as the size of the VFA was reduced, shoot growth/tree decreased at a greater rate than yield/tree. This meant that peach trees could be planted at high density in small VFA's and increase yield/acre with less pruning/area than the standard tree density. Developing high density peach production systems that use sod management to control shoot growth has the potential to increase yield/acre while reducing labor costs for pruning. In addition, the increased grass cover in the orchard will reduce soil erosion and rainfall runoff.
Mature peach trees were grown in 6 sizes of vegetation-free areas (VFA) (0.36 to 13 m2) with and without stage III drip irrigation for a six year period. Trunk cross-sectional area, total yield and yield of large fruit/tree, and pruning weight/tree increased with increasing VFA. The application of supplemental irrigation increased yield of large fruit and leaf N% in all VFA's. Winter hardiness was not affected by either size of the VFA or irrigation. The yield efficiency of total fruit yield and large fruit decreased with increasing size of VFA's. Sod management was an effective and low cost approach to controlling peach tree size and when combined with irrigated, high density production offers a potential for increased productivity.