i think the little yellowed three leaved plant may be trillium? not sure if the tall sprout is like the other plant, plus a foreign grass? these were from a very kind lady who sent me natives and i lost the markers of course.
I agree, the tall one is a goldenrod mixed in with some grass. Can't see the third plant your're talking about but if you think its a trillium then I would get it out of that pot as soon as possible. It can't compete with vigorous growers like goldenrod and grass.