Question for the Hive Mind: Roadside Weeds / Wildflowers

The second and third of these are technically not roadside plants, but the first one is:



I don't recall ever seeing it before, but they're everywhere all of a sudden.

UPDATE: it's a Vernonia (ironweed), possibly V. baldwinii. Thanks to Claude and joeym.

The other two plants were in a heavily wooded park in Iowa City about a week ago. The first, I'm fairly sure, is some kind of Arisaema. I