What is this vine that I encountered today? I was coaxing plain old boston ivy to climb the chain-link fence in our yard in Arlington, Virginia. In a shady spot, I began pulling out a vine from within the boston ivy on the fence, because though similar to the boston ivy but with maple-like leaves. Then I noticed the leaves of three. I've looked at so many pictures on your site, but I havn't found a close enough match. (I guess I will know in 3 days) Is it possible for a poison ivy vine to have a small percentage of leaves that are only one leaflet as opposed to three? This mystery plant(shown in a card board box)looks like 2 different vines, but I think they are attached!?!

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