En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - What to do with ailing live oak trees

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
Not Yet Rated

Tuesday - May 04, 2010

From: San Antonio, TX
Region: Southwest
Topic: Trees
Title: What to do with ailing live oak trees
Answered by: Nan Hampton and Eric Beckers

QUESTION:

We live in far north San Antonio, TX on a 2 acre lot with many trees.. about 25% oak and 75% cedar. About 15% of our live oak trees have not sprouted leaves yet this spring, or have only sprouted leaves on the lower part of the tree trunk where the canopy begins. These same trees have also lost large chunks of bark, some areas as large as 20" x 7". We would love to get rid of many of the water hogging cedars so the oaks can thrive, but are afraid to remove too many of them in case we get hit with oak wilt (a cedar tree is better than no tree at all). Do you think this damage Is a result of stress on the trees from last years record drought? What should we do to help these trees survive? Should we paint the areas that have lost bark or cut them away? Any help would be appreciated. Thank you.

ANSWER:

Mr. Smarty Plants contacted Eric Beckers form the Texas Forest Service about this question.  Here is what he said:

"We're hearing this over and over again and we'll probably hear about it throughout the new year.  After being stressed by the drought many of our oaks were further damaged by Hypoxylon and borers.  As soon as you hear someone say the bark has fallen off, you can bet that their drought stressed tree has hypoxylon cankers (first brown and powdery, and then a silvery crust) and the prognosis is not good."  

Go to the  TAMU AgriLife Extension Plant Pathology page to find three fact sheets about hypoxylon:  Hypoxylon Fact Sheet #1, Hypoxylon Fact Sheet #2, and Hypoxylon Fact Sheet #3. 

Since you live in San Antonio, your trees aren't likely to be affected by oak wilt.  Eric continued:

"If you live in the areas north of a Wimberley to Kyle line then there is the chance that oak wilt could be at play as well.  Trees damaged by oak wilt can also display hypoxylon cankers, so then we look for the pattern of mortality, groups of oaks dying side by side, and the brown vein leaves.  Drought mortality accompanied by hypoxylon cankers usually occurs on one or two oaks over here and another two or three over there—the sick trees are scattered about with healthy ones in between."

However, you should visit the Texas Oak Wilt site to familiarize yourself with the symptoms, prevention and treatment of the disease.

We are very sorry about your trees and hope that you are able to save some of them.  If you are interested in replacing them, you can visit our Texas-South Recommended page to find trees for your area.  Actually, since San Antonio is right on the line between the two regions, the Texas-Central Recommended page would have some tree species appropriate to your area, also.


 

More Trees Questions

Damage to native elm in Texas
August 20, 2008 - We had a major landscape renovation done over the winter. One of the trees, an elm about 10 yrs old, remained in the bed although plants around it were removed. The tree has suddenly started turning...
view the full question and answer

Ornamental plants for under live oaks
September 08, 2008 - What ornamental plant will do well under Live Oak trees?
view the full question and answer

Mixed native plantings for steep slope in Austin
April 18, 2007 - Dear Mr. Smarty Plants: We wrote to you recently about plantings for a fairly steep slope in a park in Austin. We had asked about grasses and perennials. An article about planting on slopes in this mo...
view the full question and answer

How do you determine male persimmon seedlings from the females?
May 11, 2013 - I have got new persimmon seedlings about 3 inches tall this spring, and am wondering if there is any way to tell male from female at this young stage? I just don't want to plant 20 or 40 seedlings an...
view the full question and answer

Replacing Drought-Stricken Cedars
January 16, 2012 - Hello, I live in Williamson County on a couple acres. We have several dead cedars as a result of drought; we're reluctant to cut them down because many of them provide a friendly barrier between us...
view the full question and answer

Smarty Plants's Facebook profile Support the Wildflower Center by Donating Online or Becoming a Member today.

Mr. Smarty Plants wants you to be his Facebook friend. Click the Facebook icon to add yourself to Mr. Smarty Plants list of friends.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | SITEMAP
© 2014 Lady Bird Johnson Wildflower Center