You can't confuse the two, just stay away from white berries and stick to the deep crimson berries. Poison Sumac berries are soft, whereas the Staghorn berries, if you can call them that, are hard, pellet like and grow in tall, compacted clusters. Poison Sumac berries are not in clusters, the are more berry-like, but I wouldn't advise touching the plant or the berries due to the volatile components of the sap which are extremely irritating I assure you, producing a rash similar to poison oak or ivy.
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