Impact of Nursery Root Pruning and Tree Orientation at Planting on Growth and Anchorage

Root pruning by shaving 12 L container root balls when shifting to 51 L containers did not impact Acer rubrum L. or Quercus virginiana Mill. root architecture within the top 12 cm of planted 51 L root balls five years later, despite marked differences at planting, and had no impact on tree height or trunk diameter increase. Root pruning in the nursery did not affect bending stress required to tilt Acer trunks up to five degrees (anchorage) either one, two, or three years after landscape planting. In contrast, anchorage was greater the second year after planting Quercus that were root pruned. Rotating trees 180 degrees at planting from their orientation in the nursery had no impact on Acer or Quercus anchorage, tree height, or trunk diameter. Rotating oak (not maple) trees 180 degrees at planting increased root cross-sectional area growing from the hot (south) side of the root ball when trees were rotated at planting.