By John Thomas
Box Butte Co
ALLIANCE, Neb. – In recent years, more growers in the central high plains are moving toward direct harvest of dry edible beans instead of the conventional method of undercutting or rodding, windrowing, and then combining. Direct harvest is accomplished by one pass with the combine. Producers in other growing regions, including North Dakota, Michigan and Canada, are using direct harvest for the majority of their dry bean acres.
Following are some reasons to consider direct harvest:
• Fewer harvest operations. This can translate into time and money saved.
• Early morning cutting and windrowing operations when the vines are tough are not needed. This is a labor consideration.
• Risk of wind moving windrows or rain mudding in or damaging the pods after cutting is eliminated.
• No soil disturbance and more residues remain in the field.
• Less soil through the combine if direct harvesting correctly.
n With all these advantages then, why isn’t everyone direct harvesting? Every production system has pros and cons that growers have to weigh to see if it fits their operations. Some of the reasons people aren’t direct harvesting
Normally need to wait longer to get the crop out of the field, although crop desiccants can reduce this waiting time.
• Need to learn a new production system.
• Need to buy a new or different combine header.
• A neighbor or nearby grower had a disaster.
• Total harvest loss can be higher.
Harvest loss is often the major concern with direct harvest of dry beans. Using conventional harvest methods, an average yield loss of about 1.5 bushels per acre total harvest loss can be expected in good conditions. This is based on research done in a two-year study on 24 farms by the University of Nebraska Panhandle Center. If conditions are poor with significant wind or rain after cutting, bean yield losses can go up significantly.
Further data gathered by on farm research in the Panhandle indicates direct harvest losses for pintos would average 2-3 bushels per acre, and great northerns 3-4 bushels per acre, if good field practices are followed. In a survey of 18 harvested fields in 2015, harvest loss ranged from 1.5 to 11.7 bushels per acre. Twelve of the 18 fields had harvest loss less than 4 bushels acre. This data indicates dry beans can be direct harvested with acceptable harvest losses, but if pods are too low (less than two inches above soil) or the header is held above the soil surface by ridging or an uneven surface, harvest loss can be very high.
For successful direct harvest, focus on a good yielding, upright variety with good height and long branches, very level soil surface, early uniform vigorous plants, good herbicide weed control, and a combine header that has been designed for direct harvest of dry edible beans (flex draper heads work well). The combine operator has to pay attention to adjustments, keeping the header as close to the ground as possible and reducing speed as necessary to reduce harvest loss. It is important the operator gets out of the combine and monitors his harvest loss by doing some loss counts as fields and combining conditions change. By planning for direct harvest and paying attention to some details, harvest loss can be kept at acceptable levels.
For an extensive guide to the direct harvest system, and more accurate means to determine harvest loss, see “Direct harvest of Dry Edible Beans,” EC309, on the University of Nebraska web site extensionpublications.unl.edu/assets/pdf/ec309.pdf.