What would you plant in your roadside ditch?

I want to provide a screen for some privacy between the road and the property. In our area, this needs to be at least 30ft from the center of the road or it might get cut. This leaves that spot between the break and the road. What would you plant there to make the space be useful?

It would be good if it could attract birds, bugs, butterflies and similar for either food or habitat (with the knowledge that it might get mowed a couple times a year.
It needs to regrow because the town might mow it a couple times a year.
I don't plan to eat anything from that side due to all potential for runoff from the road.
It needs to be hearty because of all the salt that comes off the road in the winter.
The spot is about 500 feet long, so it needs to be affordable to do for a long stretch.

Any ideas?

Black Oil Sunflowers offers food for birds, you, etc.

Joe Pyle Weed for Monarch Butterflies.