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Saturday - April 30, 2011

From: Pflugerville, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Pruning oaks in August from Pflugerville TX
Answered by: Barbara Medford


Can I do minor pruning on my Lacey oak and bur oak in August if it is hot and dry? I'd like to prune one limb from each. The Lacey oak limb is about 2 inches in diameter, and the bur oak limb is about 5 inches in diameter. If I prune, should I use pruning paint?


The first thing that comes to mind when we are asked about pruning any oak at any time of the year is Oak Wilt, and we suggest you read the website Oak Wilt Information Partnership to assure you are proceeding safely. To quote from that site:

"All oaks (Quercus spp.) are susceptible to oak wilt to some degree, but some species are affected more than others. Red oaks, particularly Spanish oak (Q. buckleyi), Texas red oak (Q. texana), Shumard oak (Q. shumardii), and blackjack oak (Q. marilandica), are extremely susceptible and may play a unique role in the establishment of new oak wilt infections.

White oaks, including post oak (Q. stellata), bur oak (Q. macrocarpa), Mexican white oak (Q. polymorpha), white shin oak (Q. sinuata var. breviloba), Durand oak (Q. sinuata), Lacey oak (Q. laceyi), and chinkapin oak (Q. muehlenbergii), are resistant to the fungus and rarely die from oak wilt."
You can see that your two oaks are at a lower risk of oak wilt, but caution is always recommended.

If you choose to prune in August, the Texas Forest Service recommends that you always paint pruning cuts as soon as the cuts are made. When pruning cuts are made during the proper times of the year there still may be a few contaminated nitudulid beetles in the area. If the pruning cuts are painted with a pruning paint or latex paint this will prevent these sapfeeding Nitidulid beetles from feeding and infecting your oak tree with the oak wilt fungus.


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