Live oak trimming in San Antonio

When to trim a live oak

Because of oak wilt, Texas A&M Forest Service advises against pruning or wounding oaks from February through June. Many San Antonio arborists schedule live oak work from July through January, and the coldest and hottest stretches are usually considered the lowest risk. Whenever an oak is cut, the wound should be painted right away to keep the beetles that spread oak wilt away from it.

If a storm breaks a limb during the high-risk season, the broken stub still needs a clean cut and paint. That's an exception to the calendar, not a reason to wait. More about oak wilt.

What good live oak trimming looks like

• Clearance: raising low limbs over the roof, driveway and sidewalk, and keeping branches off the house.
• Deadwood: removing dead and dying branches, which are the ones most likely to fall.
• Light thinning: selectively removing crossing or crowded branches so wind can pass through.
• Proper cuts: just outside the branch collar, never flush with the trunk and never leaving long stubs.

Avoid “lion-tailing” (stripping all the inner branches and leaving foliage only at the tips) and topping. Both weaken the tree.

Ball moss

The gray tufts on many San Antonio live oaks are usually ball moss. It isn't a parasite and doesn't feed on the tree, but heavy growth on shaded inner branches can look untidy. Removing it is mostly cosmetic and is often done along with deadwood removal.

What to ask before you hire

• Will you follow Texas A&M Forest Service oak wilt guidelines and paint every cut?
• Which limbs will you remove, and why?
• Do you carry liability insurance? Can I see the certificate?
• Is cleanup and haul-away included?