One issue that impacts soybean harvest in the eastern Corn Belt at some level each year is green stem syndrome. Green stem syndrome could be larger issue for the 2017 harvest because of latter planting dates in many areas. When green stem syndrome occurs, stems and leaves can remain green after pods have matured. As a result, while pods and seeds are mature and dry enough to be harvested, harvest operations can be slowed as combines have more difficulty dealing with stems and leaves that are still green. In addition to creating harvest delays, green stem syndrome can increase fuel consumption and result in shattering losses if growers delay harvest until stems have fully matured.
The occurrence of green stems varies from year-to-year and can be affected by several factors, such as:
• Viral infections
• Insect feeding
• Late planting
• Drought stress
• Application of fungicides.
Successful management of green stem syndrome requires management practices that include timely planting, establishing adequate plant stands, irrigation, and controlling insects/pests. By making these management practices a priority, growers can minimize the likelihood that green stem syndrome will develop in their soybean fields. Although green stem syndrome slows down harvest, soybeans should be harvested as soon as pods are fully mature in order to minimize harvest losses due to shattering.