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
4 ratings

Friday - August 12, 2011

From: Corinth, TX
Region: Southwest
Topic: Diseases and Disorders, Watering, Trees
Title: Cedar elm with brown leaves
Answered by: Nan Hampton

QUESTION:

Dear Mr. Smarty Plants, We feel we may have limited time to save our beautiful Ceder Elm. We have many trees in our yard (Post Oaks and Cedar Elms) and have been told they are all between 50 - 75 years old.About two months ago we noticed one of the Cedar Elms started to get rust colored edges on all the leaves. I thought it was because we had not had much rain and tried deep watering. This month however several entire branches have turned brown. I think the tree may have Bacterial Leaf Scorch. Any advice you may be able to offer would be so greatly appreciated. Also thank you for reading my email. Grace Ward

ANSWER:

It is possible that your Ulmus crassifolia (Cedar elm) has bacterial leaf scorch.  TAMU AgriLIFE Extension Texas Plant Disease Handbook's entry for Elm (Ulmus spp.) lists common diseases and pests and elm bacterial leaf scorch is listed as one of them.  This article from the United States National Arboretum certainly describes symptoms similar to those of your trees, however, the article says:

"The challenge is that the symptoms can be easily mistaken for physiological leaf scorch or early fall color. However, since a number of other diseases, as well as cultural problems, can mimic bacterial leaf scorch symptoms, it has been recommended that suspected infections be confirmed by sending samples to a diagnostic clinic before concluding the tree is infected with the bacterium."

If your tree does have bacterial leaf scorch, I'm afraid there isn't any effective treatment for it—either for curing it or preventing it.  The best thing you can do is to prune and keep the tree looking as nice as possible for as long as possible until it dies.  You can check with your Denton County Texas AgriLIFE Extension Service office to see if bacterial leaf scorch has been reported in the area.  A professional arborist should be able to tell you if your tree is infected with bacterial leaf scorch.   You can go to TreesAreGood.com and plug in your zipcode to find a professional arborist for your area.

Even though bacterial leaf scorch is a possibility, given the severity and length of our current drought, your tree may just be experiencing drought stress even though it is described as a drought tolerant tree. You said that you had done some watering.  Are you still watering?   If you aren't watering, you should be.  You can find an article from the City of Austin Urban Forestry Division, Supplemental Watering of Trees During Periods of Drought, with detailed recommendations on how much and how to water as well as other measures that will help drought-stressed trees.  I do know that cedar elms are one of the first deciduous trees to turn yellow and lose their leaves in the fall.  Your tree may just be reacting to the stress by doing this earlier than usual and may leafout normally in the spring.  Watering will help it recover if that is the case.

 

From the Image Gallery


Cedar elm
Ulmus crassifolia

Cedar elm
Ulmus crassifolia

Cedar elm
Ulmus crassifolia

More Trees Questions

Apache Pine for Dripping Springs, TX.
July 02, 2014 - Is the Apache Pine tree a good choice for planting in alkaline soil with excellent drainage?
view the full question and answer

Is a permit needed to plant liveoaks on property or on easement
May 25, 2007 - My house is located behind 1431 in Williamson county My backyard faces 1431 hwy and the noise and view aren't pleasant. I'm trying to plant some live oaks behind the wall and, of course, some in m...
view the full question and answer

Replacement evergreens under power line in Wisconsin
April 11, 2013 - I have to replace evergreen trees in a privacy screen due to borer damage. The screen is below power lines so the replacements cannot be tall. I would like use bird and pollinator friendly replaceme...
view the full question and answer

Pruning guidance for Carolina buckthorn from Houston
October 23, 2012 - I have a Carolina Buckthorn in my back patio that I planted in fall 2001. The summer of 2003 the roofers dropped something off the back and broke the top 10-12 inches off. I have tried to train the la...
view the full question and answer

Evergreen sumacs for privacy along fence
August 02, 2014 - I would like to plant enough Evergreen Sumacs along our fence for privacy for the length of our backyard which is 60 ft. Fifteen feet on the left and right ends are shaded with the right side being d...
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