Cameron Mills probably reads more herbicide labels than anyone else around, and that might even include some chemical dealers and custom applicators. Mills, Walton, no-tills and bases his farming operation on using cover crops to improve soil health, capture nitrogen and other nutrients and hold them into the following season.

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"I check literally hundreds of herbicide labels," he says. "What I'm usually most concerned about is what the label says about carryover injury potential to other crops. In other words, what is the plant back restriction after application before you can plant a certain crop?"

Where is the cover crop? Cover crop failures have multiple causes. One of them can be seeding too soon after an herbicide with a long plant-back restriction for those crops. Check out herbicide labels.

The crops he's usually looking for are annual ryegrass and rapeseed. That's his primary cover crop mix used on most of his acres, although he uses a cocktail mix of various cover crops following wheat.

His goal is to get cover crops started as soon as possible into the standing crop, but he knows he must balance that against possible restrictions for the cover crop he is growing based on the chemicals that he applies.

So why check the labels before spraying? Mills does it because he is so committed to making the cover crop work that he will switch herbicides if necessary to lessen the risk of problems seeding cover crops. He typically seeds into green soybeans and green corn in late summer before the cash crops are mature.

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He has seen what happens when one tries seeding a cover crop too soon after chemicals with relatively long plant-back restrictions for things like annual ryegrass were applied. Sometimes it happens because the farmer didn't realize that it was an issue, or didn't disclose everything he applied on the field to the person helping him plan his cover crop program. The results can be fields with very little cover crop cover, simply because the herbicide left in the soil wipes out the seedlings trying to germinate.

The Website Mills uses most often to find labels is cdms.net. This is a repository of labels for a wide range of herbicides.