Reduce Soybean Harvest Losses with Proper Combine Setup

By Blake Jackson

Missouri soybean growers have spent much of the growing season protecting their crop, from planting and spraying to scouting fields and managing unpredictable weather.

As harvest begins, many major production decisions are already behind them. However, how efficiently soybeans are harvested can still have a meaningful effect on the final return, according to Seed World.

University of Missouri Extension estimates that losing four to five soybeans per square foot can translate to approximately one bushel per acre. Across hundreds or thousands of acres, seemingly minor losses can quickly become a significant amount of grain left in the field.

Focus on the Header

The combined header is responsible for a large share of soybean harvest losses. MU Extension estimates that roughly 80% of losses occur at the header, making header management an important starting point when evaluating combined performance.

Cutting height is especially important. Missouri research found only about 0.3% yield loss when soybeans were cut at 2 inches. Losses increased to 2.6% at 4 inches and 9.5% at 6 inches. Growers must balance a low cutting height with field conditions, including rocks, uneven terrain, residue and other obstacles.

Short soybean plants and low pods can make cutting height even more critical. Lodged plants may also require adjustments. Excessive ground speed or an improperly configured header can push plants forward, knock pods from stems or leave plants lying close to the soil.

Pay Attention to Moisture

Soybean moisture can change rapidly during harvest. Delaying harvest may produce drier grain, but increasingly brittle pods can shatter and drop beans before they enter the combine. MU Extension notes that harvesting very dry soybeans during periods of increased humidity can sometimes help limit shattering.

Extremely dry grain can also reduce the weight sold because soybeans contain less water. Although the number of beans harvested may be similar, exceptionally dry soybeans can weigh less at the scale.

Inspect Fields After Harvesting

Yield monitors provide valuable information, but growers should also physically inspect the field. Before harvesting, check for naturally occurring beans on the ground.

After the combine passes, examine several locations for loose beans, missed plants, open pods and grain discharged from the rear.

If losses are excessive, adjust one combine setting at a time. Ground speed, reel position, cutter-bar height, rotor or cylinder settings, fan speed and sieve adjustments can influence performance.

Harvest conditions can change throughout the day, so settings that worked earlier may need to be modified later. Taking a few minutes to inspect the field and combine performance can help Missouri growers capture more of the soybean crop they worked throughout the season to produce.

Photo Credit: istock-ds70