By Randy Buhler

Colorado State University Cooperative Extension

Logan County Agent (Agronomy)

Would you be interested in a method to increase your available soil moisture by 50 percent? This is for the mechanically minded dryland producers who are trying to grow milo and it works for dryland corn growers.

You have probably noticed that the outside row or two grows better than the inside field rows, or that plants by a skip grow better than plants in a full stand. This difference is due to extra available soil moisture.

The method we are considering is skip row planting. Every third row remains blank. This leaves an additional 33 percent of your soil profile available for use by the remaining two rows. This adds 50 percent more soil moisture to each of the remaining rows. The method is designed for 30-inch rows.

The Areawide Pest Management for Wheat project of the USDA Agricultural Research Service featured this idea in the February issue of Plain View. Many companies have reported on the Nebraska skip-row study.

Milo has an ability to wait on dry soil conditions for a lengthy time until rain comes. In our region, this can result in milo not maturing before frost hits. Corn needs sufficient moisture at the right time in order to fill the cob with grain. Not enough moisture at the right time results in poor grain production.

Why would we not plant every row at a thinner rate? Generally, we think of a uniform stand as being equally spaced in every direction. Interplant competition in the row results in substantially equal exploration of the soil profile by the roots. Between row competition occurs later, but is also substantially equal. Placing an additional distance between rows delays the exploration and use of soil moisture in that space.

Seed drop per foot of row needs to remain the same as you would normally plant. This reduces your total population by one-third. It also cuts your seed cost by one-third. The University of Nebraska is experimenting with a planting pattern of two rows skipped and two rows planted.

With the planned gaps in your stand, weed control becomes critical. Your herbicide program must be good, or a planned cultivation that cleans the skip row is required. Nebraska recommends planting into good Wheat stubble cover. Follow harvest with a burn-down herbicide treatment and use another burn-down treatment prior to planting. Roundup Ready corn gives you an advantage to achieve weed free skip rows.

One caveat of this method concerns crop insurance. In 2004, policies did not cover this practice. Before using this method, check with your insurance carrier to get coverage for this specific practice. It should be available this year, or you may need to try NAP for coverage.

The only reason to do this process is as a management practice to mitigate low soil moisture storage. If you have sufficient soil moisture to fill a 5-foot profile and expect timely summer rains, then this method does not make sense. On the other hand, if you have experienced the more normal conditions for our area, this method could make a difference on getting milo to mature, or corn to fill better.

To set up a 30-inch row planter, start at the middle of the planter bar. Working out from the center, leave one planter unit on the bar, remove the next row, and leave the next two rows on for an 8-row planter. Set your marker for one additional 30-inch spacing so you can get the next skip row. For a 6-row or 12-row planter, you do not need to change the markers. The 2 by 2-row pattern works well on an 8-row planter by just removing units.

This is just an idea for you to try. It has had good results in the Amarillo region. I have seen similar results in fields that accidentally had skip rows. The University of Nebraska has measured yield increases of over 30 percent on dryland corn grown in the panhandle.

Consider your field production history and the likely continuation of drought in our region. Having the additional 50 percent soil moisture for the remaining rows could make the difference in having mature grain sorghum and better yields of corn or milo.

Date: 3/23/05