Toxicodendron diversilobum (synonymous with Rhus diversiloba), is commonly called poison oak. It is noted for causing significant and long-lasting skin irritations (allergic dermatitis) in most humans who come into contact with the plant.
Auxinic herbicides such as triclopyr, 2,4-D, dicamba, and combinations of these herbicides also control poison oak. You can apply these herbicides earlier than glyphosate, when plants are growing rapidly from spring to midsummer. Triclopyr is the most effective auxinic herbicide for poison oak control.
Poison ivy is a common poisonous plant that causes an itchy skin rash. Other rash-inducing poisonous plants include poison oak and poison sumac. These plants produce an oily sap called urushiol that brings on an irritating, itchy allergic reaction. Poison oak is a small shrub. The plant, which is also known as Rhus diversiloba or Toxicondendron diversilobum, is found in the western United States. Like poison ivy, poison oak leaves change color with the seasons. The plant also produces white berries in the fall.
