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Thursday - July 07, 2016

From: Crawford, TX
Region: Southwest
Topic: Pruning, Trees
Title: Removing Old Poison Ivy Vines from Pecan Trees
Answered by: Anne Van Nest

QUESTION:

I am in the process of cleaning up a creek bank that has very old pecan trees on it. The pecan trees have large poison ivy vines growing up the trunks. We cut one vine and when it died and fell from tree it pulled large chunks of bark and the tree died. Is there a safe way to kill ivy without harming the trees?

ANSWER:

Sorry for the delay in replying to your question.

There are several ways to tackle poison ivy removal from trees but no matter which method you try, make sure you approach it with caution if you are allergic to the sap (and particularly the urushiol within it). The Clueless Gardeners blog online has a good article about the extreme precautions that should be taken by susceptible people when working around this plant. http://thecluelessgardeners.blogspot.ca/2008/03/poison-ivy-removal.html

Now for the removal ... the two options are to paint on an herbicide (poison ivy killer or non-selective herbicide) without getting it on the pecan trunk or cut the vines near the base of the trunk and carefully pry them off the tree when they start to shrivel. Be careful, even though the plant may look dead there is still urushiol oils present that could cause problems in humans. Be wary of the saw dust and do not burn the plant as the oils could get into your lungs.

And lastly, make sure everyone can identify poison ivy in all its forms and stays clear of it until it is off the tree.

The www.wildflower.org website describes it as an upright, climbing, or trailing shrub that bears small yellowish-white flower clusters; old stems, covered with fibrous roots, look hairy. Poison Ivy is extremely variable in form, occurring as a ground cover along roadsides, an erect shrub (especially in sandy coastal areas), or a large vine on trees. Red fall foliage is especially conspicuous.

From the Image Gallery

Eastern poison ivy
Toxicodendron radicans

Texas poison ivy
Toxicodendron radicans ssp. verrucosum