En EspaŅol

Q. Who is Mr. Smarty Plants?

A: There are those who suspect Wildflower Center volunteers are the culpable and capable culprits. Yet, others think staff members play some, albeit small, role. You can torture us with your plant questions, but we will never reveal the Green Guru's secret identity.

Help us grow by giving to the Plant Database Fund or by becoming a member

Did you know you can access the Native Plant Information Network with your web-enabled smartphone?


Ask Mr. Smarty Plants

Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.

Search Smarty Plants
See a list of all Smarty Plants questions
Can't find the answer in our existing FAQs, submit a question to Mr. Smarty Plants.
Need help with plant identification, visit the plant identification page.
rate this answer
1 rating

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.


More Diseases and Disorders Questions

How to treat bark damage on oak tree
November 15, 2011 - I have an oak tree approx. 50 ft., live in austin, texas. the tree has dropped bark about 3-4 ft above ground, in a section of 4 inches by 8 inches, and the tree appears dark where the bark was. is ...
view the full question and answer

Problems with non-native weeping willow from Hazlet NJ
July 03, 2013 - Leaves turning yellow on weeping willow planted in May. What causes this and how can I fix it? Mother's Day gift after SANDY uprooted huge tree.
view the full question and answer

Freeze damage to Mexican olive in Austin
December 13, 2009 - I have a Mexican Olive tree/bush. It is young - about 8 ft. tall. This last freeze in Austin made many of its leaves turn black. I got this from your database: "Its native range extends no farther...
view the full question and answer

Freeze-damaged Texas Mountain Laurel in Austin, TX.
May 05, 2011 - I have a Texas Mountain Laurel (Sophora secundiflora) that is several years old. During this past winter, one of the freezes we had split one of the largest trunk right below the soil line. T...
view the full question and answer

Tip Dieback on Lonicera sempervirens
August 14, 2013 - I have a Lonicera sempervirens (coral honeysuckle) vine in Virginia which does well early in the season, but then around July, the very tips of its shoots (just the last 1-2 inches) wither, turn black...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
© 2015 Lady Bird Johnson Wildflower Center