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

Saturday - August 04, 2012

From: Austin, TX
Region: Southwest
Topic: Diseases and Disorders, Trees
Title: Problems with Cedar Elm in Austin, TX.
Answered by: Jimmy Mills

QUESTION:

Our Cedar Elm has yellowing very dry leaves and something is eating the topmost leaves leaving holes and obviously chewed off leaf segments. Could this be two different things? Aphids and bacteria or Dutch Elm? We planted the Treefolks sapling four years ago. It has adequate water, a mulch berm, has not been sprayed and we are concerned about insecticides, but will try anything. Thanks!

ANSWER:

Cedar ElmUlmus crassifolia (Cedar elm) with its glossy green leaves, smaller than those of American Elm, is an attractive landscape plant.  (more info) 

Mr. Smarty Plant has found that is is very hard to diagnose tree problems from a written description, but you have given some clues that will allow some reasonable guesses. Along with my guesses, I will provide some links that will help you determine what the problem may be.

The symptoms you describe; yellowing , dry leaves with the top-most leaves showing evidence of a chewing insect perhaps, could be caused by several things, but Dutch Elm Disease is probably not one of them.

Dutch Elm Disease (DED) is caused by the fungus Ophiostoma novo-ulmi which is introduced to the tree by the native elm bark beetle, Hylurgopinus rufipes and the lesser European bark beetle, Scolytus multistriatus.

The first symptom observed in American elm is yellow foliage on one or more branches, from late spring to midsummer. The affected foliage soon becomes wilted and brown; this symptom is called "flagging." This doesn’t sound like what you described. These three links have more information about the disease.

     texasinvasives.org

    USDA Forest Service

    University of Illinois

Yellowing can be a symptom caused by an aphid infestation, which seems to be common in Austin this summer. This link from  UC Davis  describes the pests and possible control measures.

Another pest  that could account for the yellowing is spidermites. Reading the two links below could make you a neighborhood expert on these little plant suckers.

      Colorado State University

      UC Davis 

Bacterial leaf scorch can cause yellowing, but the images shown in these two sources don’t look to me like what you described.

     Bartlett Tree Research

     The United States Nattional Arboretum

Since aphids and spidermites lack chewing mouth parts, we can’t blame the chewed leaves on them, however a possible culprit could be the Elm leaf beetle. The two links below give details about these destructive bugs.

    Colorado State University 

     University of Illinois 

The bottom line is that you need someone knowledgeable about tree sto take a look at your elm tree to make an assessment of the situation. This person could be a Certified Arborist , or someone from the Travis County Office of Texas AgriLife Extension.

 

From the Image Gallery


Cedar elm
Ulmus crassifolia

More Diseases and Disorders Questions

Problems with Mountain Laurel in Leander TX
June 15, 2009 - My 13 yr old Mountain Laurel tree is sick. It has lost most of its leaves after blooming this spring. The twigs seem to still be pliable so I assume alive. I saw no moth worms or bags this year, ju...
view the full question and answer

Oak tree with browning leaves in Brenham TX
August 16, 2011 - I have a large oak tree in my small back yard. I also have a sprinkler so the tree has been receiving some water. Nevertheless, some of the leaves are turning brown in patches. Would drip watering ...
view the full question and answer

Problems with non-native zucchini in Muskogee, OK
July 23, 2011 - In the awful heat of this summer I am still getting zucchini to produce. But, once it grows about 3 inches, it gets yellow on the ends and dies. Am I watering it too much? (I have sprayed for bugs ...
view the full question and answer

Possible disease on Eastern Redbud
October 06, 2007 - Our Eastern Redbud appears to be suffering from our recent drought. The leaves are turning brown in July/August on a few branches. A few black spots appear on the leaves before they turn brown. Ot...
view the full question and answer

What is eating the plants in my garden?
August 08, 2008 - I have both purple and yellow coneflowers. Something is coming into my garden and eating the flowers off the stems. We don't have deer but may have other small animals that can get into our yard. Do ...
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