About the sumac, I’ve never seen it flower like that. But maybe it’s never grown to this size here. So, perhaps I’ll leave some to find out.
Re the birch, I asked my wife about it and she said she didn’t think birch grew here. But, I thought there might be more than one species. It turns out the bark looks like either a sweet, river or yellow birch. It almost looks like black cherry bark, but I’ve never seen it bloom, so it’s got to be birch.
Re the poplar, it looks like it probably is, but I don’t recall it blooming, but I may have missed it.
The last two pics are of the same tree, the poplar.