u/Chernobog2

Had this tree planted late last year, but starting to wonder if it's planted too deep (or if the surrounding mulch/dirt is too high).

Dug down a bit and think I found the start of the root flair, but would like some confirmation before I do anything more.

Zone 5a (Wisconsin, United States).

First time seeing this. Afraid of this being knotweed, but this doesn't quite seem to match?