I have been using Kaltenberg corn in Wisconsin. They are a family owned company specializing in locally adapted northern seed. They have a couple numbers that seem to do well on clay hillside strips.

http://www.kaltenbergseeds.com/

Wyffels is a corn-only family owned company based in Illinois. I was very impressed by their people and the program they put together at a recent meeting I attended.

http://www.wyffels.com/index.html

Both companies seem very customer oriented and specialize. It seems like they fill a need in the seed market.

Jim at Dawn