Should I Cut the Lower Branches off a 20-Foot Pine Tree?

Pruning the lower branches from a mature pine tree (Pinus spp.) is a "could," not a "should." It's a discretionary haircut that improves access under the tree, if that's desired. But like every cut on a coniferous evergreen, you need to prune lower branches -- if at all -- at the right time and in the right way.

How Pines Grow

Before you pick up the pruner, be sure you understand how pine growth differs from other trees. Other coniferous evergreen species grow dense, overlapping branches that shade out areas of the canopy near the trunk. You should never prune into that area since no new growth is possible. Pines do not self-shade in this way, however, but instead produce whorls of branches separated vertically from other whorls by an internode of trunk. A primary purpose of pruning a young pine is to shorten the space between whorls. Once a tree is mature, this kind of shaping is no longer feasible.

Pruning Mature Pine Trees

Established pine trees need little maintenance clipping if the tree is planted correctly in its appropriate hardiness zones. The zones vary among species, ranging from U.S. Department of Agriculture plant hardiness zones 3 through 9. Most pines have strong central leaders that don't need any help or training, assuming a classic pine pyramid shape is desired. Mandatory pruning is generally limited to removing dead or diseased limbs at the point they emerge from the trunk.

Optional Pine Pruning

Some homeowners opt to remove the lower branches from their backyard pines. This is desirable if you need to have more access to the area under the tree. Removing lower branches won't hurt a pine. In fact, you can remove the lower third of the crown without damaging a healthy pine, according to forestry experts at the University of Idaho's Cooperative Extension System. However, the tree may be happier and is certainly more beautiful with its full crown intact, so only cut if you feel it truly necessary.

Removing Lower Branches

If you decide to remove your pine's lower branches, do so when the tree is not in its growth phase that lasts from spring through summer. The best time to act is late winter. Use a hand saw that cuts on the pull stroke, cleaned before each use with a rag dipped in denatured alcohol. Make the cuts just outside the limb collar, the slight swelling where the branch emerges from the trunk. For large, heavy branches, employ a three-cut process. First make a cut 12 to 24 inches from the base of the limb on the lower side of the branch. Cut about a third of the way through the branch. Second, cut right through the branch from above, just outside the initial cut. Make the final cut just outside the limb collar to remove the branch stub.