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?

Share

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
Not Yet Rated

Friday - September 05, 2008

From: Plano, TX
Region: Southwest
Topic: Trees
Title: Bur oak defoliation
Answered by: Joe Marcus

QUESTION:

I have a bur oak that was planted in 1993. In 2000, I had mortared stone edging (approx 5 inches deep) installed around the trunk from 4 to 6 feet away. In the last 3 years, the tree seems to be declining (early defoliation, almost dead leaves on one side at the top, khaki-colored foliage in July). I am willing to remove the edging if it will help. My questions are these: 1) Do you think the edging is the problem? 2)If it is removed, will the tree roots grow out or have I created a bowl where the roots will continue to grow circularly?

ANSWER:

The mortared edging you installed eight years has almost certainly had no part in creating on the condtion you've described.  However, we are not sure just what is causing the problem.  Well-established bur oaks rarely suffer from diseases, those they are notably susceptible to cotton root rot (Phymatotrichum omnivorum) and Strumella canker (Strumella corymeoidea).  Cotton root rot is a particulary common problem in your area in North Texas.  The most common and troublesome oak disease in Texas, Oak Wilt, does not often affect bur oaks, though it can and does occasionally.  Finally, various insects and mites can attack bur oak foliage, disfiguring and even killing the affected leaves.

Environmental changes in the root zone can cause tree defoliation and decline.  If you have made any major changes to the soil within the root zone of the tree - especially changes in watering, herbicide applications, any trenching, or any changes in soil depth in the last couple of years, those changes could be the cause. 

It would be best to have a certified arborist examine your tree to help you determine just what is causing the symptoms you're seeing. 

 

More Trees Questions

Privacy Screen Tree for Patio in NC
April 15, 2013 - What is a good tree to plant in front of a brick wall/fence to provide privacy and not compromise the structural integrity of the wall? The brick fence is my neighbors but I need privacy as they can s...
view the full question and answer

Huisache blooms when freeze is over
May 02, 2005 - I live in San Antonio, TX and have heard that when the Huisache blooms all danger of frost or freeze is over. Is that true? And, this year to date (April 22, 2005) we have not seen the Huisache bloo...
view the full question and answer

Symmetrical Holes in Live Oak leaves.
April 08, 2009 - We have 2 young live oaks - quercus virginianum trees and their brand new leaves show two symmetrical rows of pin-sized holes punctured along the length of them. What could have caused this?
view the full question and answer

Secretions of fluid from crepe myrtles
June 09, 2008 - On my crepe myrtle tree I have dozens of 1/2-inch-long narrow bugs that seem to secrete tiny drops of fluid. They appear on the branches of the tree. Are these harmful to the tree? Do I need to do ...
view the full question and answer

Tree Recommendations for Hutto, TX
September 28, 2014 - I live in Hutto, TX. I want shade trees in my back yard. I would like a fast growing tree as well as a slower growing tree. What trees are recommended for my area?
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