En Español

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

Please forgive us, but Mr. Smarty Plants has been overwhelmed by a flood of mail and must take a break for awhile to catch up. We hope to be accepting new questions again soon. Thank you!

Need help with plant identification, visit the plant identification page.

 
rate this answer
1 rating

Friday - December 26, 2008

From: Flower Mound, TX
Region: Southwest
Topic: Diseases and Disorders
Title: Exposed area on native elm in Texas
Answered by: Barbara Medford

QUESTION:

I have an elm tree starting to show signs of dying. It has an exposed area at the trunk of the tree turning white. When it rains there is a 6-inch strip (the width of the exposed area) running up the tree that does not soak up the moisture. This is a great shade tree in the summer and I would like to save it from dying. The tree is around 12 years old. What can I do to save my tree? Thank you, Dan

ANSWER:

Basic elements that influence tree health include sufficient oxygen in the soil, water and light and a proper balance of nutrients. Too much or too little of any of these environmental conditions may cause plant stress. Urban trees often have paving over some of their roots, and can also be affected by pollution. These and other environmental conditions may weaken the tree and makes them more susceptible to insect and disease attacks.  The elm is not generally a long-lived tree, probably because of the problems to which it is susceptible, but 12 years is not very long in tree life.

Of course, the first thing that comes to mind when an elm tree is in trouble is Dutch Elm Disease, which is an almost-always fatal disease of elms. You did not say which elm you had. In Texas, the native elms are Ulmus americana (American elm), which is highly susceptible to the disease, as well as Ulmus alata (winged elm), Ulmus crassifolia (cedar elm), and Ulmus rubra (slippery elm), all of which range from susceptible to somewhat resistant. This site from National Forestry Services Identify and Manage Dutch Elm Disease will give you extensive information on symptoms, prevention and treatment of the disease.

However, the symptoms as you have described them sound more like a canker disease. The information and pictures in this site from Kansas State University Extension Plant Pathology Canker Disease in Elm Trees is more specific. As a rule, Ulmus americana (American elm) and Ulmus rubra (slippery elm) are not severely damaged by cankers. To try to avoid cankers developing, avoid bark injury, such as being bumped by machinery or mowers and edgers. Prune out branches exhibiting cankers and remove them. Some more pictures of cankers.

It is difficult to diagnose or recommend treatment from a distance. We suggest you contact the Texas A&M Agrilife Extension Office in either Tarrant or Denton counties. Both linked websites have contact information, and they would be in a better position to know about disease or pests of the elm trees in your area. It would probably also be advisable to have a licensed arborist look at the tree and see if any treatment is feasible.


Ulmus alata

Ulmus alata

Ulmus americana

Ulmus americana

Ulmus crassifolia

Ulmus crassifolia

Ulmus rubra

Ulmus rubra

 

 

 

More Diseases and Disorders Questions

Why are my Junipers turning brown in San Antonio?
May 11, 2009 - My Texas mountain cedars (junipers, I know) are turning brown, limb by limb. What is the problem and how do I save what looks like a dying tree.
view the full question and answer

Growing Dwarf Yaupon Holly in Texas
December 04, 2013 - We planted 10 extra dwarf yaupons in our Austin front yard. They were identified as 'Gremici' dwarf yaupon. I googled them to get more information about them in order to determine why five have di...
view the full question and answer

Protection of American beautyberry in Pennsylvania
July 30, 2007 - I have had a beauty berry 2 years now. I trim it back in early spring and it returns beautifully. ...but no flowers this year and it's almost August. Last year, very few berries. Can you help? I...
view the full question and answer

When is the best time to trim oak trees in Driftwood TX?
September 09, 2010 - When is the best time to trim oak trees?
view the full question and answer

Pecan tree dropping limbs in Grand Prairie, TX.
September 04, 2012 - Our 15 year old pecan tree is losing it's limbs. The tree and its leaves look healthy with no signs of bugs or mites, but all the limbs are drooping and breaking off. The tree did have a bumper crop ...
view the full question and answer

Support the Wildflower Center by Donating Online or Becoming a Member today.
E-NEWSLETTER | BECOME A MEMBER | DONATE NOW | MEDIA | JOBS | SITEMAP | STAFF INTRANET
© 2016 Lady Bird Johnson Wildflower Center