Avoiding poison ivy this summer may be harder than you think. According to a local expert it’s extremely hard to positively identify the noxious weed, despite the old adage “leaves of three, let it be.”

Marr Park Naturalist Pam Holz says there are many variables that make identification difficult. For one, poison ivy can be dull or shiny and any shade of green. It’s also supposed to be a woody vine, but it can be flexible and sometimes isn’t a vine.

She says if you do run into this plant, take a hot shower and wash anything else that may have come into contact, like clothing, in hot water. She explains cold water is unable to remove the plant’s oil which causes the irritation.