marijuana? the leaves certainly look suspicious.

Lol I hope not! :D It's more tree like.

Fear not! Looks like a mulberry tree to me.

Oh thank you! :D Does it have invasive roots I wonder..and how did I ever end up having a mulberry in here, that is a question. :))

It's a mulberry and was probably "bird planted", pooped out by a bird sitting on the fence. Get rid of it.

Too bad, the seedling looks nice and healthy. Why exactly it's a bad choice to leave it be?

Seriously, look it up.

Seriously, look it up.