En Espa—ol
Share

Ask Mr. Smarty Plants

Mr. Smarty Plants - Pruning mature cedar elm trees in San Antonio

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
17 ratings

Sunday - September 14, 2008

From: San Antonio, TX
Region: Southwest
Topic: Diseases and Disorders, Pruning, Trees
Title: Pruning mature cedar elm trees in San Antonio
Answered by: Barbara Medford

QUESTION:

When is the right time to prune my several mature cedar elm trees? I'm in San Antonio, and they have never been trimmed in the 55 years we have lived in this home. I have several that are at least 70 ft tall and they need cleaning up. I wouldn't want to harm them, though.

ANSWER:

Ulmus crassifolia (cedar elm) is a native North American deciduous tree which reach 50 to 90 feet in height with a spread of 40 to 60 feet. It would be a low maintenance shade and street tree except for its thin drooping branches which are somewhat susceptible to breakage at the crotches of major limbs. Some of this could be avoided by maintaining a regular pruning and training program in the early years after transplanting. For more information, see this USDA Forest Service website on Cedar Elm.Your elms have already had a pretty good life span, at 55+ years, and are at a height to be expected at their age. They have a fairly long life span, perhaps 150 to 300 years. So, at first glance, we could say your elms have been doing just fine, and need no trimming, etc.

However, the main drawback to the elm is Dutch elm disease. Dutch elm disease was first discovered in Ohio in 1930. Spores of the disease are carried on the bodies of elm bark beetles and are deposited in tree wounds. The beetles, perhaps introduced accidentally from Asia, attacked trees that had not had a chance to develop a resistance to the disease over time. It is caused by a fungus transmitted by two species of bark beetles.

Avoid pruning from April to August. The elm bark beetle is attracted to freshly cut elm and is most active during this period. Prune dead or dying branches from Fall to late Winter. We would urge you to engage a licensed arborist, for several reasons. They will be aware of the potential problems for the elm tree, and know when is the appropriate time for pruning. Also, they will have the equipment and expertise for dealing with such a large tree. Please don't climb up your trees with a chain saw. You will possibly damage a whole lot more than the tree.


Ulmus crassifolia

Ulmus crassifolia

Ulmus crassifolia

Ulmus crassifolia

 

 

More Pruning Questions

Pruning Texas Mountain Laurel
November 12, 2009 - How much can I prune a 10 year old mountain laurel to re-shape it and when?
view the full question and answer

Should black-eyed susan (Rudbeckia hirta) plants be cut back
May 02, 2007 - I have black-eyed susan plants that were beautiful last year and flowered for a long time. Do they need to be cut back and if so, how much?
view the full question and answer

Cutting back woody plants after freeze in Leander TX
December 10, 2009 - I have several woody shrubs in a prominent location. Now that the leaves have frozen, how far back should I cut them? These are Flame Acanthus, Salvia ballotiflora, and Aloysia macrostachya, but I w...
view the full question and answer

Suckers from Oak Tree Roots in Austin
May 17, 2013 - Hi. I am a home owner in Austin TX with several live oak trees. We love them and want to keep them healthy. We have a nice landscape in the back yard and Iím wondering if you can answer a quest...
view the full question and answer

Late winter pruning of native Texas Sage
January 27, 2005 - I have several Texas Sage bushes that have started to get very woody and have growth only on the top. This seems to have led to a definite listing to one side. Should I trim these to the ground or...
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