A few people have already complained about poison oak/ivy and how to eliminate the noxious weed. Both poison oak and ivy contain powerful compounds which produce a painful rash severe enough in some instances to hospitalize those with extreme allergies.

The poisonous substance which causes skin rash found in the leaves and stems is called urushiol. Urushiol is also found in all parts of the plant: roots, bark, berries and stems. Minute amounts of this poisonous oil often causes a skin rash that penetrates within minutes after contact. However, in some instances it may take up to 10 days may before a rash will appear.

Now is an excellent time to control poison ivy. Brush killer herbicides that contain dicamba or trichlopyr on the label should be sprayed on the foliage now while the plants are actively growing. Other herbicides that contain glyphosate (Roundup) also kills the plant systemically destroying underground rhizomes. Wear long-sleeved shirts, long pants and protective gloves (plastic disposable gloves are ideal) when working in patches of poison ivy. Follow instructions provided by the label before application of any pesticide. Go to https://plants.ces.ncsu.edu/plants/all/toxicodendron-radicans/ for more detailed information.

Darrell Blackwelder is the retired horticulture agent with the North Carolina Cooperative Extension Service in Rowan County. Contact him at deblackw@ncsu.edu.