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Saturday - October 03, 2009

From: San Antonio, TX
Region: Southwest
Topic: Pruning, Trees
Title: Lifespan and pruning of cedar elm in San Antonio
Answered by: Barbara Medford


How long do cedar elm trees live? How can you estimate the age of one, or tell if it is nearing the end of its normal lifespan? Do you have any recommendations for selecting someone to prune it properly? Thank you!


The lifespan of any tree is an estimate at best, because record-keeping was not as intensive 100 years ago as now. You can look at a tree and check its height and diameter at chest height, but since you don't know when that tree first grew from a seed, about the best you can do is guess. The USDA Forest Service Climate Change Tree Atlas says the typical lifespan of the cedar elm is approximately 100 years; however, it has a question mark for the maximum lifespan. 

This tree is reasonably fast growing, and its height at maturity ranges from 20 to 94 feet, with the shorter maximum heights occurring in areas like the Edwards Plateau, where growing conditions tend to be more difficult. A mature tree averages a 36" diameter at chest height. A tree that is beginning to have branches die is probably approaching its maximum age. The cedar elm is also susceptible to Dutch elm disease, which will kill the elm.

Ulmus crassifolia (cedar elm) certainly needs to be pruned for removal of weak crotches that might result in breakage, as well as shape, particularly in the early years of the tree.  You want to find someone who is a licensed, trained arborist to properly prune. If you go to our Native Plant Suppliers section, you can type your town and state in the "Enter Search Location" box and you will get a list of native plant nurseries, seed suppliers and landscape and environment consultants in your general area. If you find a company specializing in tree care in that list, contact them and find out the training and qualifications of the arborist who will work on the tree. 

From our Native Plant Image Gallery:

Ulmus crassifolia

Ulmus crassifolia

Ulmus crassifolia

Ulmus crassifolia




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