Effect of Trellis Height and Crossarm Width and Angle on Yield of Thompson Seedless Grapes

Abstract

A three year study was made on Thompson Seedless grapes to determine the effects of trellis height and crossarm width and angle on vine production. The vines were trained to trellis heights of 1.4 m, 1.7 m and 2.0 m with no crossarms, 0.6 m crossarms, and 1.2 m crossarms positioned horizontally and at a 45° angle. Trellises 1.7 m and 2.0 m in height resulted in greater pruning weights and more clusters and crop per vine than did the lowest trellis (1.4 m). Total yield and yield per retained node were greater with 1.2 m wide crossarms during one season. There were no significant interactions detected for height x width.