Ask Mr. Smarty Plants is a free service provided by the staff and volunteers at the Lady Bird Johnson Wildflower Center.
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.
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
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.
Existing live oak taking over in Monahans TX
March 22, 2011 - I have just purchased a home with a huge Live Oak tree in the front yard. The previous owners have over the years allowed the sucker roots to grow unchecked. The tree is shading most of the lawn (di...
view the full question and answer
Care of Northern honeysuckle bush
April 26, 2009 - I have a honeysuckle bush, I have had it for about year to two years. I would like to know if I should cut the brown parts off. There are some vines that do not look good, but some of the branches ha...
view the full question and answer
Corkscrew willow damage to roof in Detroit, MI.
August 13, 2009 - I have a corkscrew willow (Detroit, MI) that is huge and whose branches hang on top of the asphalt shingles of my mobile home. It has now been discovered that these shingles, under the branches, are ...
view the full question and answer
Pruning of Burning Bush in Missouri
October 15, 2008 - I live in MO and am pretty sure I have burning bushes on either side of my deck. My question is that they are huge and overgrown but I feel if I cut them lower and shape the sides up I will be left w...
view the full question and answer
Hedge of native Purple Sage in Austin
November 20, 2008 - Hi,
I would like to plant a dense hedge of Purple Sage that will hopefully grow from 6-8 ' tall and about 4' wide. I purchased the Silverado Sage Leucophyllum frutescens 'Berstar Dwarf' variety....
view the full question and answer
![]() |
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. |