Willow oak is a large shade tree native to the eastern and southeastern United States. It is widely planted as a shade tree in urban areas and grows to a height of over 70 feet with a spread of up to 50 feet. It grows in a pyramidal shape when young and develops into a rounded canopy as it ages. The lower leaves also begin to droop as the tree ages. Willow oaks create deep, dense shade and grow well planted on boulevards or in parking lot medians.
Remove any branches that are competing with the central leader. Willow oak should be pruned to have only one central leader, or trunk. Do this early in the life of the tree, removing all upright-growing branches that compete with central leader.
Remove any dead, diseased or broken branches. Make the cut flush with the trunk of the tree.
Cut off some of the large branches developing along the trunk so the remaining branches are evenly spaced and grow off the tree at an angle larger than 45 degrees.
Prune out some of the mature branches in the crown, removing no more than one-third of them. This will force the remaining major limbs to develop more secondary branches along their length and improve the willow oak's ability to withstand high winds without breaking.
Remove low-growing branches to keep them out of the way of pedestrian or vehicle traffic. Willow oak branches droop as the tree ages and some branches that were formerly high enough to allow for such traffic beneath them may droop much lower and need to be removed later in the life of the tree.