This little plant is a volunteer in my back yard. It is growing in an area with dozens of other plants, but it's not a familiar seedling.
If no one recognizes it, I'll probably leave it where it is and wait for it to produce flowers.


The first leaves were somewhat heart-shaped.

Nope - not poison ivy.

Are there older specimens around? It looks as if it may form more leaflets as it matures.

I haven't seen any; however, when looking around my yard for possible parent plants, I noticed that the seedling's leaves have traits in common with those on a nearby Viburnum 'Shasta'.
I couldn't find online images of Viburnum 'Shasta' seedlings for comparison, though.

Yes - opposite arrangement rules out Toxicodendron radicans. If it is a woody plant, it could be a seedling (or root sprout) from Elderberry (Sambucus canadensis) - or rarer Bladdernut (Staphylea trifolia).

There don't seem to be buds at the base of the compound leaves where they attach to the stem. That points to an herbaceous plant (annual or perennial). There are way too many herbaceous species with pinnate compound opposite arranged leaves - some of which are pretty pernicious weeds - for me to narrow them down.

Cross posted with Muddy's reply...

No, not 'Shasta' or any other viburnum due to pinnate compound foliage. Viburnums will always have simple leaves.

Now - if your 'Shasta' is displaying compound leaves of any sort, I may just show up in dark of night and snatch some cuttings...

I do have Sambucus canadensis growing nearby, so that's a possibility, although I agree it might not be a woody plant. Time will tell.

In the meantime, here are some photos of my Viburnum 'Shasta'.

I can tell that I'll need to wait for this plant to grow some more before it can be identified, so I'll close this thread for now.

For some reason Elderberry comes to mind. It has been many years but it was a common pop up plant in VA.

I have mature Elderberries (Sambucus canadensis) growing nearby, so it could well be an Elderberry seedling. I couldn't find photos online of S. canadensis seedlings of that size for comparison, though.

It looks very much like Ground Elder. A proper thug in any garden !