Pruning Lower Branches of Live Oak (Quercus virginiana Mill.) Cultivars and Seedlings during Nursery Production: Balancing Growth and Efficiency

Abstract

Abstract Tree production requires time for pruning to meet customer expectations, yet pruning can slow growth and increase the time (and cost) to prepare trees for market. Our research quantifies trade-offs between growth and pruning. In two separate locations, over two time periods, we found no difference in caliper growth between trees with only the largest one or two low branches removed at each pruning, compared with trees having all lower branches shortened. Acorn-propagated and Cathedral Oak® Quercus virginiana (Mill.) with all branches removed from the lower 1.37 m (4.5 ft) of trunk (temporary branches destined to be removed to produce a trunk clear of branches and a distinct canopy) by 18 months after planting had smaller caliper than other pruning treatments; however, pruning these branches had no impact on the Highrise® cultivar. Removing the largest one or two low branches at each pruning was the most efficient pruning method tested. Removing all temporary branches in February of the last year of production (2004) did not reduce caliper, height, or canopy spread compared to removing half in February and half in October. Since there was no difference in time required for pruning, we suggest removing branches early in the last growing season for more completely closed wounds and enhanced customer appeal.