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

Wednesday - April 04, 2012

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders, Pruning, Trees
Title: Red oaks that didn't drop leaves in Austin
Answered by: Barbara Medford

QUESTION:

I have a number of Red Oaks on land that did not drop leaves this past fall. Now these same trees seem to be dead? It seems there's some type of mold/fungus on the trees. Some trees have small patches of this stuff while others have it up and down the whole trunk. If I cut the trees down will it spread? Is it bad, should I worry? Anything help?

ANSWER:

A group of volunteers at the Lady Bird Johnson Wildflower tree were looking at  Quercus buckleyi (Texas red oak) on the grounds of the Center. It also had not lost its leaves, which were quite brown. Damon Waitt, the Senior Botanist, did the "thumbnail" test, scratching a very thin sliver of bark off a large limb, and found a layer of green beneath it, which indicated the tree was still alive. The stems were also limber. The conclusion was that the tree would probably survive. Even though the Wildflower Center does do some irrigation, we were limited, like everyone else in Austin, to as little as possible last year, and as you know, it did not rain. Now, of course, some things we thought were dead, shrubs, trees, etc. are popping leaves out and carrying on. Hopefully, so will your tree. In fact, more recently, we passed that tree and it is leafing out like crazy.

However, (isn't there always a "however"?) the description of the fungi on your tree trunks is pretty alarming. Oak Wilt, a scourge of red oaks, is a fungus transported by the nitiludid beetle. A wound in the bark, as from an unpainted pruning scar or damage from a weedeater or lawnmower, will exude a sap, which is ambrosia to the beetle. If he has been feeding somewhere else in oak sap, perhaps from a tree already infected by Oak Wilt, the fungus spores will infect the new tree.

Since we are not plant pathologists and certainly couldn't diagnose this problem sight unseen, we want to refer you to a website that should be able to help you. First of all, you are going to need professional help from a trained, licensed arborist. The Texas Oak Wilt Partnership, in which the Lady Bird Johnson Wildflower Center is an active partner, should be looked at closely. Under "Getting Help" you will find out you are in the Austin District, and get names and contact information on Oak Wilt specialists.

This is the time of year when the nitiludid beetle, spreader of Oak Wilt, is most active, so if the tree is infected, you will need to take the advice of the expert you bring in on whether to cut it down now or wait until the dormant months of December and January and also on how to protect other oak trees in the vicinity.

 

From the Image Gallery


Texas red oak
Quercus buckleyi

Texas red oak
Quercus buckleyi

More Pruning Questions

Trimming of Flame acanthus from Bastrop TX
February 17, 2012 - My flame acanthus never lost leaves off the bottom tier of branches this winter. With the brief warm weather and rain we've had, the top and middle tier of branches have all re-leafed. It is very l...
view the full question and answer

Pruning of Grape Kool Aid Plant in California
August 03, 2008 - I have a Grape Kool Aid plant and was told it would grow to 6 or 7 feet tall, but it is well over that and I need to know if I can prune it and if so how?
view the full question and answer

Shearing Pink Skullcaps
September 21, 2014 - My pink skullcap plants keep dying. The ones that are still alive are about 3 years old, but have large sections of dry twigs. Do I shear them and hope they come back or are they gone? I live in Helot...
view the full question and answer

Pruning of tree poppy from Livermore CA
May 29, 2013 - We have a Dendromecon rigida which has been in place for about 10 years and is doing fine. But the older growth gets dry, brown and crinkly, while the newer growth is bright and lush. I would like t...
view the full question and answer

Young yaupon trunks bending in Houston
April 26, 2010 - I have new yaupon in this their second summer which are bending over about half-way up their trunk, at around two feet - do I trim them or stake them?
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 | STAFF
© 2015 Lady Bird Johnson Wildflower Center