Poison sumac (Rhus Vernix or Toxicodendron)

This shrub like tree can grow up to 20 feet tall, it has two parallel sets of leaves 7 to 13 on each leaf stem and the leaves are up to 4 inches long, with one at the very end making it an uneven number of leaves. It’s tiny red flattened round berry clusters grow in panicles these turn white in the fall. Most Sumac species are dioecious (male and female on separate plants). Roots are shallow, about 10 cm deep but will stretch out to 12 feet around to look for suitable light or soil conditions. It’s branches and trunk are slightly spiked to the touch.

The more common Staghorn Sumac has red fuzzy clusters of flowers and velvety branches, hence the name.

Positive:  berries are loved by birds and flowers by insects
                 Tolerant of poor soils
                 Keeps soil on banks from eroding
                 Often used to create hedges or windbreakers forming dense thickets
                 Drought resistant
                 Leaves are known for its beautiful fall colours

                   Can grow rapidly and overtake or displace native plant and animal species 
                   Its growth can block rain, sun and change soil chemistry, temperature and can cut off native plant’s access to nutrients and prevent new understory growth.
                   Grows faster than the invasive Holly and Laurel!
                    Poison Sumac is also known as “Thunderwood”.

The fruit and leaves of this shrub/tree can cause severe blistering that can persist for several weeks. Poison Sumac contains urushiol, an oil that causes a rash on contact with skin and can damage eyesight when sap gets in the eyes.  
This plant is more toxic than poison oak and poison ivy.  Do not burn any part of this shrub as inhaling its smoke can damage lungs and the smoke can irritate eyes.


– Chemical pesticide injected in stem (much like knotweed species)
– Shredding, trunk, branches and leaves (Wear a mask and gloves)
– Digging, out clones (suckers) and plants, as long as the original trees are still growing, it can be expected that clones will reappear continuously. It is suggested to cut clones in Spring and Fall and (if all including original plant is removed!) in 3 to 4 years the plant will get exhausted and give up …..