How can I recognize a poison ivy plant stem or vine in all seasons?
Answer: Look for the very hairy stem, the slightly hairy stem, multi-vine hairy stems, or the smooth stem. This is where poison ivy identification gets a little tricky.
Why do leaflets have different looks?
The answer: Because they are doing different jobs. The baby leaves of a poison ivy seedling growing in its first year. The edges of the leaves are toothed and terminal leaf has short neck. Toothing of leaves facilitates good water evaporation which leads to quick growth.