"I don't know what the SC is."

SC is Seed Consultant.  It is the brand that is sold in the Eastern US.  There was another brand - Doebler's I believe - that was a regional brand, and it was folded into Seed Consultant brand in the previous consolidation.

Hogemeyer is not known at all here in the East.  

Dairyland Brand was previously known for alfalfa seed. I guess that is gone? (I recall hearing that Pioneer no longer sells alfalfa seed.  I think I am correct on that.)