Selecting the right grain sorghum hybrid is essential for producers who are hoping to plant wheat after sorghum harvest in the fall. Growers, who planted sorghum on time, or even early, and harvested the crop on time or early, may see less yield loss in double-cropped wheat.

Growers who planted sorghum based solely on yield potential may expect more problems with the following wheat crop.

Hybrids with early vigor, good dry-down traits, insect and disease resistance and some drought tolerance may be an advantage when planting wheat behind sorghum.

Earlier maturing sorghum hybrids will provide the greatest potential for an early harvest. With the right genetics and management practices, many early and medium-early hybrids can produce yields that compete with the longer-season hybrids in the Midwest.

When considering planting wheat behind grain sorghum, it may be beneficial to take a close look at the growth characteristics of the variety they planted.

When considering planting wheat in the fall after sorghum harvest, wider rows in the preceding sorghum crop may be beneficial. Sorghum planted into narrow-rows tends to produce more biomass, but not necessarily yield. The increase in residue could create a better environment for toxins from the sorghum plant and could exacerbate yield problems associated with a soybean and wheat double-crop.

On the negative side, narrow-rows have historically meant higher sorghum yields, probably because of better shading out of weeds early in the growing season.

In fields with a history of weed problems, growers may need to carefully evaluate the trade-off between yield loss from competition with weeds in wider row spacing versus greater potential for yield loss from toxins from sorghum in following wheat crops.

North Carolina growers alone are expected to plant nearly a million acres of wheat this fall. Though only about 50,000 acres of grain sorghum was harvested this year, that number is expected to increase in the next few years and growers planning to plant it and double-crop it with wheat need to be aware of potential yield drag in such a cropping system.

rroberson@farmpress.com