sorry, yes

Thank you, cecily. Sigh.

There are a few varieties of Toxicodendron radicans. They differ in leaf shapes, but the terminal leaflets will always have longer petiolules than the side leaflets. This plant looks like variety negundo, which resembles Box Elder leaves.

Thank you, Jay.

Let me annotate what Jay properly said. The petioles are the stalks that join the leaf to the main stem. The distinguishing feature for Toxicodendron (beyond three shiny leaves) is that the petiole on the end leaf is longer than on the side leaves. If that's not the case, it isn't poison anything.