Poison-Ivy

Poison-ivy (Toxicodendron radicans) is a native woody, perennial vine.
Poison-Ivy - Articles
Poison-Ivy

Photo: Charles T. Bryson, USDA Agricultural Research Service, Bugwood.org eastern poison-ivy Toxicodendron radicans

Though it doesn’t pose the problem in terms of nutrient and water competition that a majority of other common weed species do, it has its own significant pest quality.

My guess is that you are all aware of it. All parts of poison-ivy contain resinous compounds called urushiols. When urushiols contact the skin, or are inhaled, they cause inflammation, itching, and blistering.

You don't even have to contact the plant directly. The liquid can get on tools, pets, or clothing and when you touch them, you can pick it up. It can also be inhaled when it becomes a gas when poison-ivy is burnt. Dead plant material contains the urushiols too. Nasty stuff!

You have to use caution when eradicating this weed. Poison-ivy reproduces primarily from seed that is dispersed by birds when they eat the fruit. It can also spread from the root stock and stems that can root to surfaces, such as a tree trunk. Poison-ivy is a vine that grows vertically as it attaches to various structures, but it also becomes a ground cover when it can't grow upwards. Leaflets are in groups of 3 and can be smooth, toothed or lobed. This is different from another common native vine, Virginia creeper, which has leaflets in groups of 5. The foliage turns red in the winter.

One option for managing poison-ivy is the use of goats. Goats love to eat this plant! Is this a practical option for most of you? I would guess no, but seriously consider it if the situation lends itself to their use. Herbicide options are limited to glufosinate-ammonium (Finale) as a foliar burndown application. This active ingredient does not translocate. It may not kill larger plants, which may be hard to treat in their entirety.

Glyphosate (Roundup and others) can be applied to foliage, or to the vine via cutting and squirting/wicking into the wound. The "glove of death" can also be used for precise foliar application. If you are not familiar with this method, put on a chemical resistant glove (nitrile and some rubber ones can be used) then put on a fabric or cotton glove. Apply concentrated glyphosate on the outer glove then touch the plant.

Authors

Integrated Pest Management Entomology Horticulture

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