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Monday - February 22, 2016

From: Denton, TX
Region: Southwest
Topic: Poisonous Plants, Problem Plants, Shrubs, Vines
Title: How to Control Poison Ivy
Answered by: Anne Van Nest

QUESTION:

We have lots of Poison Ivy on a site we are clearing it is adjacent to a pond and children are around this area all the time. We are creating hiking paths. I have a lot of experience but I do not want to spray with an herbicide or Round up or anything toxic. How can we rid large areas of it? Of course there are so many recipes and ideas, but I want to know what we can do that truly works. We have vines climbing trees as well as low 2-3' stalks coming up from the ground. At one point we covered a lot of it with eastern red cedar branch blankets but we are back to late winter and about to enter into spring and I see them coming up around these areas we laid cedar branches. Can you truly smother it with heavy debris or lay down plastic? I have read a lot about vinegar and salt combo? Is this practical? Thank you for your advice.

ANSWER:

Poison ivy is certainly a big challenge to control because of the persistent nature of the plant but also because of the hazards of working around the plant. If you are susceptible to Urushiol (the ingredient in the sap that causes the nasty rashes) like 80% of the population, you will have to be extremely vigilant in identifying the plant and when handling it. Remember that poison ivy can be a vine, shrub or groundcover type plant.

A layer of heavy debris will not smother poison ivy. It will just slow it down and the plant will continue to grow toward the light. A very thick layer (or two) of black plastic should be enough to smother the offending plants. I would suggest cutting the plants off at the ground and then laying the plastic over the soil, securing the edges with soil. Do not poke any holes into the plastic or else the plant may find that pinhole and grow through it. Be extremely careful when handling the pruned poison ivy pieces as well as when near the remaining pruned stem at the soil level. Sap will still be present.

Vinegar and salt will only work if enough is used and they are strong enough to cause significant damage to the soil also.

From the Image Gallery

Eastern poison ivy
Toxicodendron radicans