Poison ivy (Rhus radicans) is a poisonous vine with surface oil that irritates human skin. Within a few hours and up to a day after contact, skin may itch, blisters sometimes form and inflammation is common. For control of this toxic plant, utilize herbicidal sprays to kill poison ivy.
Glyphosate is a nonselective herbicide used to control and kill poison ivy. Since this herbicide is nonselective, it kills all plant material and is not just formulated to destroy poison ivy. Use with caution to avoid accidental death of wanted plants, according to the Michigan State University Department of Forestry. Poison ivy is often present on trees; if applying glyphosate to ivy on a tree, be careful that the herbicide only comes into contact with tree bark and no other part of the tree to prevent damage, according to the Iowa State University Extension.
Amitrole is a control herbicide used to kill poison ivy. A nonselective herbicide like glyphosate, amitrole is known for its low toxicity to wildlife and humans, according to the Cornell University Extoxnet. Spray amitrole directly onto poison ivy foliage. Unlike glyphosate that does not remain active in soil, amitrole travels through the plant after application to foliage and, once in the soil, provides residual activity for many weeks, according to the Michigan State University Department of Forestry. Wait to plant anything new in soil that may contain active amitrole.
The growth regulator herbicide 2,4-DP (dichlorprop) is an effective spray used to kill poison ivy, according to the Iowa State University Extension. Other plants are easily damaged by contact with this herbicide. Take caution to use a spray container for 2,4-DP alone without using it for other herbicides as the smallest amount of 2,4-DP can severely damage plants, even in such small amounts as residue from a container mixed with some other chemical. Additionally, wait to apply this herbicide to poison ivy if rainfall is likely within 10 hours as water will decrease effectiveness, according to the Michigan State University Department of Forestry. More than one application may be necessary for destruction of the poison ivy root system.