Small grain farmers in drought-prone areas of the state may have another combining option in the future that can boost profits while conserving essential natural resources, according to researchers with the Agricultural Research Service.
Researchers Brien Henry, Merle Vigil and David Nielsen of the Central Great Plains Research Station in Akron, Colo., recently released the results of a four-year study which analyzed yield, residue and soil-moisture content of Proso millet under conventional combine methods and using a stripper header which is commonly used in winter wheat harvests against stripper header wheat data.
Using finger-like extensions on a rapidly-spinning drum, a stripper header removes just the head of the grain, leaving the rest of the plant standing as opposed to traditional combine headers which mow off more of the plant stalk with a sickle.
Article Photos
Submitted photo --
A stripper header in action on a field of millet in Colorado. Harvesting grains like wheat and millet with a device called a stripper header in place of a conventional combine header leaves taller crop residues, which leads to more stored moisture and reduced erosion in this photo submitted by ARS
Results of the study, published in the Agronomy Journal, showed the use of the stripper header equipment held several conservation and production advantages over traditional combining.
Of major concern for area producers is soil erosion due to wind and reduced or uneven residue on fields which can cause emergence problems for the following crop.
The study showed that using the stripper header left up to 18-inch-tall stubble as compared to 3 or 4 inches left by the combine's sickle bar. For wheat, the equipment left 2-foot-tall stubble compared to 6 to 8 inches with traditional combine equipment. The fields that underwent conventional harvest methods lost more than 30 percent of its total residue mass whereas the stripper header residue stayed intact.
It is in the tall, standing stubble, that lies the key to conservation, researchers said.
"If you have 18-inch stubble, the wind velocity at the top will be 30 miles per hour, but it will be zero at the bottom," said Merle Vigil, a soil scientist and co-author of the study. "The additional stubble helps to reduce erosion."
In addition to erosion control, stubble also helps to slow evaporation and increase absorption.
Vigil explained that light-colored stubble such as wheat reflects heat which helps to slow the rate of evaporation and the height of the stubble helps the water to better absorb by breaking the water droplet into smaller components before it hits the ground. On bare soil, he said, the rain drop, falling at 80 miles per hour, hits the ground, breaks up the soil particles and helps to seal the ground.
The tall stubble also helps to trap snow.
"The stripper header is already widely used in winter wheat production to build-up higher levels of crop residue, which increases the effectiveness of trapping snow," said David Nielsen, research agronomist and co-author of the study. "The additional stubble results in 2 inches more of water moisture for the next time you plant."
Using winter wheat as an example, he explained that the crop responds by 5 or 6 bushels per acre for each additional inch of water in the soil, so the 2 inches of stored water provided by the increased stubble could increase the winter wheat yields by 10 bushels or more per acre.
In addition to the potential increase in yields for the farmer, the study showed the use of the stripper header can be beneficial to production in other ways.
Among the advantages is time and ease of use.
"One great thing is that you don't have to pay attention as much with the stripper header as you do with a sickle," Nielsen said. "With that you need to raise or lower the head in accordance with the seed level, but all that monkeying around will slow you down. Another great aspect is that you can go three to four times faster because you don't have a cutterbar and there is less stem material in the machine, which generally slows it down."
With fuel costs still on the mind of farmers, the researchers said under the right conditions the stripper header machine could eliminate the need to swath millet and other crops, which would save fuel, labor and time. They did note, however, that seed moisture levels were higher for stripper header harvest than traditional, but it would not prohibit on-farm storage or acceptance by commercial grain elevators.
Throughout the four-year study, researchers said that average yields were similar in both conventional and stripper header harvest methods and no test weight or seed color variances due to harvest technique were noted to influence marketability of crop.
While there are several advantages to using the stripper header, the researchers noted that several risk factors exist which need to be addressed by each farm operation.
The first is the potential for a pre-harvest wet snowfall that could cause lodging or breakage of the panicle resulting in yield loss. Previous research studies about the stripper header's ability to harvest lodged crops have been inconclusive. Different studies showed that the equipment was poor at harvesting lodged rice, but good at harvesting lodged barley and winter wheat.
According to Shelbourne Reynolds, creator of the equipment, benefits of using the machine include improved performance in down, lodged and hailed crops, both in terms of crop recovery and speed as well as improved performance in green, high moisture and weed-infested crops.
"Many farmers in low rainfall areas have utilized the moisture retention benefits of stripped straw in their no-till farming systems," Reynolds said.
The other potential downside is the cost, which starts at $40,000 depending on the type and size of the equipment.
Overall, Nielsen said, the results of this study indicated that the machine can provide lower input costs, increase conservation measures and can be used effectively with various crops.
"Akron is dry and has strong winds but the results indicate that the equipment could work well in the western part of North Dakota that has similar weather and could be utilized on any small grains like barley, oats, soybean and wheat," he said.