En EspaŅol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Problems with Cedar Elm in Austin, TX.

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 Trees Questions

Privacy Screen for Heavy Clay and Full Sun in Louisiana
April 19, 2013 - What would be a fast-growing plant for privacy in Louisiana? I have heavy clay and full sun.
view the full question and answer

Flashing barrier to Bermuda in tree bed
September 16, 2007 - I'm building a 6-ft-diameter planting bed on a gentle slope on blackland clay, at the center of which I plan to install a cedar elm. I'm using the wedge-shaped stones from the home-improvement stor...
view the full question and answer

Moths around Sophora secundiflora from Driftwood TX
March 15, 2012 - Sophora secundiflora Our Mountain Laurel has a lot of large moths flying around it. Should we be concerned? Will they hurt the tree? thank you
view the full question and answer

Shade-loving plants for birds in New Jersey
March 25, 2013 - What native plants should I add to my property, Zone 6, to feed birds naturally? I have a heavily treed lot, so I'd like names of shade loving perennials. Seed or fruit bearing options would be gre...
view the full question and answer

Allelopathy of American elms from Dallas
March 24, 2013 - Are American elms at all allelopathic?
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
© 2014 Lady Bird Johnson Wildflower Center