Trying to identify the smaller seedling on the center/left of the shot with the lighter green leaves. Any ideas?
It's an ash tree. I can't tell you what kind exactly, could be any of the three common types, white, green, or black.
research EAB in your area ...
what fascinates me on these.. is that every group of what looks like 7 leaves.. is a SINGLE compound leaf ... cool eh ...
if EAB is prevalent in your area.. dont bother with it ...
if you find one SINGLE compound leaf impressive, check out a DOUBLE (bipinnately) compound leaf! Kentucky Coffee tree & Devil's Walking stick are two good examples. Honeylocust & Albizia have them too, but with really small leaflets.