Q: How can I tell if I have the poisonous kind of sumac?
A: The old adage, “three leaves let it be” does not apply to poison sumac, Toxicodendron vernix. Sumac leaves are classified as compound which means the petiole or stem arising from the bud has more than one leaf. Poison sumac has 7 to 13 leaflets. The edges of the leaflets are smooth and not toothed. Many plants put out new leaves in the spring which are pale green in color but poison sumac leaflets are bright orange making them easy to spot. These orange leaflets turn dark green and glossy as they mature. The underside of the leaflet becomes a pale green. The stem to which the leaflets attach is a red color which aides in identification once the poison sumac plant matures. Poison sumac can grow into a large shrub or even become almost tree-like.
Take great care if they need to be removed by wearing long sleeves, pants and gloves. Once shrubs have been removed be cautious about exposing skin to any part of the plant. Wash the clothing in a separate cycle from the rest of your laundry. Avoid exposure to burning brush as the smoke may irritate mouth, throat and lungs. I have attached a publication from the University of Florida/IFAS which provides more information on sumac, poison ivy and poison oak. In addition, it provides an excellent drawing to help distinguish between other plants which may look similar to poison sumac. For those of you who camp and hike, this publication might be an important document to keep in your backpack. http://edis.ifas.ufl.edu/pdffiles/EP/EP22000.pdf