Keep in seed grain

Posted by Paul on November 19, 2009 at 17:06

"Keep in seed grain"
I'm not exactly sure what it means, or its origin. Can someone help me out? Here is the sentence in its context - discussing railroad companies of the 1800s and their pricing:

The railroads appeared unhampered by the laws of competition. They seemed able to charge rates calculated to keep the farmers in seed grain - no higher, no lower.