Today there are several options for control of poison oak, poison ivy and poison sumac – and more may be
on the horizon.
Chemical treatment
One of the most effective is the use of herbicides. Two or more treatments may be needed, though, as the
plants are very persistent. Spray spreading vines with products containing glyphosate, dicamba, 2,4-D or
triclopyr, using tank mixtures of these products when possible.
When poison oak or poison ivy grows as a climbing vine, the same products can be used as a "cut
stump" treatment. Cut the stem a few inches above ground and treat the stump with your herbicide to
keep it from resprouting. Remember to always read and follow label directions before buying or using
these products.
Mechanical treatment
If the weeds are growing in an open and accessible location, mowing is a possibility. Mow repeatedly
throughout the growing season, though, or the rootstock will simply sprout new plants.
You can hand-pull or dig the plants, but you run the risk of exposure. In addition, any root stalks
missed are likely to sprout again. Don’t burn the plants you’ve removed. Toxic oils can be spread by
smoke and cause a full-body reaction. You’ll need to bury the plants in a safe spot.
Biocontrol
Biocontrol is a possible future treatment alternative.
Researchers at Virginia Tech University are exploring whether poison ivy can be controlled by a naturally
occurring fungus (Colletotrichum fioriniae). High concentrations have been used to kill seedlings in the
lab.
Further research is underway to determine whether the fungus can be applied in granular form to control
poison ivy in the wild, without impacting surrounding plants.