“Burndown” now refers to more than using herbicide chemistries to eradicate weeds. In October, our team at The Farm Research Center in Garden City, Mo., introduced a new 30-foot burndown burner that can effectively kill weeds, even those that may have herbicide resistance issues. Plus, the burndown burner may eradicate harmful insects and their eggs.
Burners use propane-fueled torches to create heat, which can control pre- and post-emergent weeds and grasses. Each 1.2 million BTU torch positioned on the burndown burner leads to generating temperatures as high as 2,200 degrees. Essentially, the extreme heat produced by the torches vaporizes water from weed cells. Without adequate cellular water content, the weeds die. Plus, heat from the burner that reaches the ground can kill weed seed within as deep as the top quarter-inch of soil.
The new burndown burner operates similarly to the in-crop burner that we at BigYield.us introduced earlier this season, but the burndown burner uniquely applies heat across a wide swath rather than target heat between crop rows. In this video, Kent Kauffman of BigYield.us shows and explains the burndown burner being used at the research center.
Burners may have application in fall or spring burndowns. If using a burner after harvest, then plan to burn within one week of the harvest date. In the spring, tilled fields can be worked, planted and then burned before the crop emerges. For no-tillers, first mow or harvest any cover crop. Follow with burning and then planting the cash crop. Avoid using a broadcast burner in dry or drought-like conditions.
On average, the broadcast burner uses 10 gallons to 13 gallons of propane per acre. To kill most broadleaf weeds, one trip across a field is typically sufficient. For thicker grasses, two trips may be necessary to effectively kill the grass cover. Assuming that a field requires one trip and that current propane prices average $0.89 per gallon, propane costs per acre would range from $8.90 to $11.57.
The Farm Research Center plans to track the effect of year-after-year burndown burning on weed populations. After using the burndown burner for multiple years, our team anticipates that the weed population and weed seedbank will drop during each successive year. Cumulatively, efforts that shrink the weed seedbank may significantly reduce weed pressure and simplify in-season weed control needs.
This story from Successful Farming shares other weed management suggestions to consider now through 2017.
Growers interested in burning fields of their own can now lease a burner from BigYield.us. For more information, please call or email anytime.