Harvest Weed Seed Control: An Integrated Approach to Sustainable Weed Management in Western Kansas

Commodities

Practices

With the rising cost of herbicides and the increasing herbicide resistance across weed species, alternate methods of weed control are of dire importance. Herbicides are under growing scrutiny for their impact on the environment and applicators, which only adds to the need for new non-chemical weed management methods. This is where HWSC offers a solution. Harvest weed seed control is an integrated approach to sustainable weed management that is available to farmers in western Kansas. This mechanical means of weed management aims to destroy weed seed that is harvested by the combine. The destruction of the weed seed leads to fewer seeds that can germinate thus alleviating the number of weeds in the soil weed seed bank. The objectives of this research are to determine the efficacy of HWSC in controlling common weeds in wheat, and to determine the economic viability of including this weed control approach in an integrated weed management program. With the main intent being weed suppression, the economic evaluation will compare the impact of a reduced weed seed bank due to HWSC with herbicides. It is expected that farmers will use less herbicides and thus see a savings on chemical, application costs, and reduce the risk herbicides pose to the environment. Reducing the amount of herbicides used will reduce the potential for water contamination. To evaluate this, researchers will harvest wheat using a combine fitted with a weed seed destruction unit. The chaff from the wheat will be run through the tailings of the combine and processed by the weed seed destructor. The weed seed destruction efficacy will be evaluated by conducting weed emergence counts in the following growing season. The results will then be compared to a control plot, which will be harvested conventionally with no destructor unit. Weed seed bank populations will also be collected to determine the level of seed carryover from the prior years. The efficacy of the weed seed destructor will be compared to that of the control to see how many weeds the mechanical mill suppressed. With successful implementation of HWSC, farmers can save money on herbicides and reduce the need for additional application trips.

Farmers will use the results from this research to justify a reduction in herbicide use in fields where HWSC has reduced inputs to the weed seedbank. Farmers will have new knowledge of mechanical weed control methods that save time and money without sacrificing efficacy. In addition, farmers will gain an understanding of the importance of multiple methods of weed control. Farmers and producers will be able to see the direct impact on their land that HWSC has. This research can increase farmers' desire to include a mechanical weed control option in their integrated weed management programs. Outcomes farmers can expect to see are reduced weed populations and reduced chemical inputs. Mechanical weed seed destruction units will be monitored to determine if sales have increased due to this new knowledge and regional surveys will be conducted to assess the general attitude toward mechanical weed control and the use of HWSC. In addition, cooperating farmers' own input will be surveyed to determine if this means of weed control is viable and interesting to them in the future.