According to the Arbor Day Tree Foundation, pecan trees are the most valuable nut-producing trees in the United States. They are the largest of the hickory trees, reaching heights of 70 to 100 feet and spreads of 40 to 75 feet in width. Arbor Day also states that pecan trees grow well in USDA hardiness zones 6 to 9 and can handle a variety of soil types. To get the most out of your pecan tree, proper pruning is in order.
Texas Pecan, a website run by the Southern Star Pecans orchard, suggests pecan trees should be trimmed in early to mid-spring. Pruning in the winter leaves the pecan tree vulnerable to the elements. They suggest you trim your pecan trees just as the leaves are sprouting.
Pecan trees need a strong central leader to have a nice, easy-to-maintain shape, according to Esteban Herrera of New Mexico State University. The key to a strong central leader is to prune one-third of the top of the pecan tree at the time of planting and to remove any side shoots and the second strongest shoots in the subsequent years of the pruning. Texas A&M says that all other branches should come off of the trunk and the central leader at a height of about 6 feet. Any growth lower than that can be cut back.
The University of Florida states that mature pecan trees do not need to be heavily trimmed if they are kept neat every year. The removal of water sprouts around the trunk and dead, damaged or diseased branches should take place yearly, as should the trimming of vertical branches. Each branch should be spaced about 18 inches apart from each other for the sunlight to penetrate into the center of the tree.