What is it? Hedge parsley!

It is not Queen Anne's lace, or water hemlock. This plant grows here in full sun to mostly shade. It varies from 18 inches to this specimen which is 3 feet tall. In the pics, just ignore the giant ragweed.

Bird's eye view shows flowers and seed heads on the same plant.


The flower umbel structure lacks bracts.


Umbel from above.


Branch structure, all stems are hairy.


Root structure.

As you probably already know, it's most likely a member of the Apiaceae family, formerly known as the Umbelliferae. But with over 3,700 species, it's really tough to figure out which one. Also, I have zero knowledge of the wildflowers of your area. But maybe  someone else from your region on this website can identify it.  If not, maybe you could check the Apiaceae section from a wildflower book for your region or show it to your local extension agent. Good luck!

Thanks.

Also, the seed heads mature into a sort of violet-brown color, fading to brown when fully dry.

does it smell like anything in particular when you crush a leaf or stem?

Does it look like this:
https://mdc.mo.gov/discover-nature/field-guide/hedge-parsley

I think you've got it! Thank you!

Here's a better description from Texas.

Here is what Plants For a Future has to say about it.