Poison Oak
Scientific Name: Toxicodendron diversilobum
Weed Family: Anicardiaceae


Poison oak is identified by 1-inch to 3-inch long leaflets with two to seven deep lobes resembling oak leaves. Lateral leaflets appear without stalks on viny stems about 3 to 4 feet tall. Like poison ivy, leaflets are grouped three per leaf, and flowers are yellowish. Poison oak is found throughout the southeast and along the Pacific coast in the United States.

Herbicide Use

Large, well-established infestations can be a problem to remove either mechanically or chemically. A series of post-emergence broadleaf herbicide foliar treatments may be required to conquer a large infestation of poison ivy or poison oak. Vines which have become well-established in trees can be practically impossible to eradicate without herbicide damage to the tree. In these situations, an ester herbicide labeled for mixing with oil for a basal stem treatment may be required. For optimum foliar control, make your herbicide application to poison oak that is actively growing and in the first trifoliate leaf to flower stage of growth.


Germination Dates

Zone-8: March-AprilZone-9: March-April