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
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

Why all the acorns from Austin
November 03, 2010 - What's the explanation for the huge crop of acorns falling from my live oak trees this fall. Do you recommend I dump them in my composter or just throw them in the flower beds? Thanking you in adv...
view the full question and answer

Possible reasons for non-fruiting wild plum
March 10, 2007 - My grandfather has land in Lee County with thickets of wild plum, I believe creek plum is another name. However, they never seem to produce plums while thickets nearby on the roadside less than one mi...
view the full question and answer

Native plants both deer resistant and good for erosion from North Oaks MN
August 23, 2012 - We have several partially sunny areas on hills that are prone to both deer and erosion. Our goal is to reduce runoff in an effort to preserve the watershed that provides tap water to many citizens of ...
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

Tree that successfully treats psoriasis
January 31, 2009 - Dear Mr. Smarty plants,I have a rather unusual question. Do you know of a tree/plant that you can grow in a container, looks like a conifer/evergreen, is green, has wispy looking branches, but when t...
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