The tricky thing about avoiding poison ivy, microbiologist John Jelesko said, is the plant is highly adaptable and can take many different forms in different environments. “It’s remarkable,” he said, with a laugh. “There’s just an enormous amount of things with this plant that are currently unknown.” He offers insights into how to recognize Toxicodendron radicans, the scientific name of the plant, before you risk touching it — and what to do if it’s too late.