No Till Notes: Two Thirds

[Editor's Note: Mark Watson has had knee surgery, and this week's column is a reprint of a previous column.]

During our field days around the Panhandle recently there was a lot of discussion on choosing a good dry land crop rotation and how choosing your rotation will really determine the success of your no till crop production system. I'd like to share some of my thoughts on choosing a good rotation and some golden rules that we go by after more than 20 years of no till farming.

I titled this article "Two-Thirds" because I think this is a good concept to remember when you are looking at developing a good consistent rotation for our region. On our farm we have decided to plan a

crop rotation that has the best chance of success year in and year out. In the past we have tried to hit home runs with some of the crops that pay out big one year but don't provide good economic return during the length of the rotation. We now have a rotation that provides us the best opportunity to

have consistent yields year after year.

Part of my golden rule of "Two-Thirds" is to plan a crop rotation in which two thirds of your crop rotation is high residue crops. In our rotation we use winter wheat followed by corn. If you are in a drier part of our region and are uncomfortable with corn as part of your dry land rotation you can substitute proso millet for the corn.

The reason I think this "Two-Thirds" rule is so critical for our area is based on the research done at Dakota Lakes Research Farm near Pierre, South Dakota. Dr. Dwayne Beck has shown over the past 20 years on his research farm that if we have crop rotations with less than two thirds high residue our winter wheat yields are basically cut in half. Dr. Beck's research has shown that a crop rotation that is half high residue crops and half low residue crops always reduces the winter wheat yields whether it is a dry year or a wet year.

Dwayne's research has shown that a soybean (low residue), corn (high residue), field pea (low residue), winter wheat (high residue) rotation results in winter wheat yields that are about half of what a

rotation of winter wheat, corn, field pea rotation produces in winter wheat yields. Rotations with half high residue and half low residue simply don't produce enough residues to make the system work.

My opinion after 20 years of no till dry land crop production in this area is that we have to do all we can to produce as good of winter wheat yields as possible to produce the residues the system needs to be successful. Winter wheat is the crop that sets up the rest of the rotation for success.

This is the reason we have included field peas as our low residue crop. The field peas provide us the best opportunity to produce a good winter wheat crop. The better our winter wheat crop with the higher residues it produces, the better chance for success we have with our dry land corn. If you produce a poor crop of winter wheat due to your crop rotation the following crop tends to suffer in yield.

Next week we'll continue with another important part of my "Two-Thirds" golden rule for dry land no till crop production.