Look at the appearance of the leaves. Leaves are an important part of identifying any plant. There are many plants that are very similar, but one of their differences can be in the specific appearance of the leaves.
Pay attention to the way the leaf is attached to the stem since this can make a huge difference in the specific plant. For example, a poison sumac has a red stem with narrow leaves that attach along the stem in leaflets that can number from seven to 13, with each leaflet attaching individually to the stem. This plant is similar to poison oak and poison ivy and can cause an annoying, itchy rash, so learn to recognize it.
Look at how complex the leaf is. Simple leaves have only one single leaf attached to the stem, while complex leaves have three or more leaflets attached to the stem to form a leaf. The complex leaves of the poison sumac can hold as many as 13 leaflets.
Look for lobes. Lobes are when leaves are rounded at the end rather than ending in a point like maples. Many lobed leaves are not poisonous although each specific plant is different.
Pay attention to whether the leaves have a fuzzy hair-like appearance or not. The poison sumac has a red stem, but not a hair-like appearance, and that is its only difference in appearance from the Staghorn sumac, which is not poisonous.