Every spring, my local gardening Facebook page starts filling up with countless pictures of three-leaved plants, each one framed with the same question: "Is this poison ivy?"
It's a legitimate concern. Poison ivy is not only invasive, but can cause a severe allergic reaction if you get its oils on your skin. I've had more than enough rashes over the course of my life to look askance at any plant that even remotely resembles poison ivy.
