Cup Plant (Silphium perfoliatum)?

Here is a link that might be useful: Cup Plant

I would lean toward one of the milkweeds (Asclepias spp.). Take a picture when the flowers are open and re-post.
hortster

Compare your plant to Eupatorium, thoroughwort.

Here is a link that might be useful: Google image results

Are the leaves alternate or opposite?

The leaves are what I would call alternate by the keys I've looked at I've thought milkweed, but it doesn't have the waxy surface of a milkweed leaf.

Anna

Asclepias includes a number of different cultivars with a wide variety of leaf shapes and flowers of many different colors. Are you familiar with butterflyweed? That's an asclepias. I'm not sure how many asclepias have waxy leaves, but not all of them.

At least some of the thoroughworts have opposite leaves.

Thanks! It should be in bloom soon and that will help a lot. I'm trying to identify it as to whether or not it's a host plant/nectar source for butterflies. If it is, I can convince hubby not to brush hog it out of existence. :)

Anna