Planning Burndown
Jan 06, 2025
January is a crucial month for Tennessee-area grain farmers. It is a prime decision time that will set a strong foundation for the upcoming growing season. Soil tests must be evaluated to fine-tune soil-nutrition plans. Seed varieties are settled upon. Equipment is evaluated, repaired, and winterized in anticipation for spring planting.
Perhaps one of the most pressing issues is spring burndown. Loosely defined, burndown is the process of eliminating weeds and cover crops prior to spring planting. A standard practice of no-till farming — which constitutes roughly 80% of Tennessee’s grain acres — burndown also helps break the “green bridge” (the transition of pests from weeds to crops) and allows the seedbed to warm up and dry out faster.
Depending on weather conditions during the winter months, burndown can begin as early as late February or early March and should be based on several variables, including crop species and variety, weather, weed pressure, plant-back restrictions, and budget.
Cullen Wiggins, Crop Protection Marketing Manager for GreenPoint Ag, says his first consideration when making burndown recommendations is the weeds that need to be controlled.
“Usually, we’re talking about three driver weeds — marestail, henbit, and Italian ryegrass,” says Wiggins. “When we’re discussing corn, we’re thinking mostly about Italian ryegrass. Mississippi State University has some great data that shows about an 8-time ROI (return on investment) on every dollar spent on controlling Italian ryegrass in corn. That tells you how important it is to get that weed killed before you put a corn seed in the ground.”
Wiggins says there is an allelopathic reaction between corn and Italian ryegrass, meaning the weed releases a chemical compound into the soil that is detrimental to the crop and negatively impacts yields.
“Because of this, it’s critical to kill that ryegrass while it’s small and before it begins to tiller in mid to late spring,” he says. “If not done in the fall, early spring is the time to address that weed if your field conditions allow. You can go ahead and put a residual herbicide in the tank mix as well to prevent any additional flushes [of ryegrass] before you get ready to plant corn.”
Because of Italian ryegrass’ resistance to glyphosate and plant back considerations with clethodim, Wiggins recommends starting with paraquat and atrazine in the tank in front of corn and then mixing with a Group 15 herbicide like WinField United’s Charger® Basic.
For marestail (or horseweed), Wiggins says, try to apply a burndown application either before or shortly after the plant bolts.
“We want to get it in that early, rosette stage,” he advises. “Glyphosate is a standard in burndown applications in Tennessee, but additional modes of actions are required to control marestail such as Sharpen®, Verdict®, or Elevore®.”
For producers who have a substantial infestation of henbit, Wiggins recommends one ounce per acre of Corteva’s Elevore® herbicide.
“That can be used in combination with glyphosate, 2,4-D, Corteva’s LeadOff ®, or a variety of other products,” he says. “And speaking of tank mix, in most cases, it will be necessary to add a good oil-based adjuvant like [WinField United] StrikeLock® to increase the efficacy of these applications.”
Regarding timing, Wiggins advises applying burndown herbicides as early as late February or the first of March.
“It all depends on the weather,” he says. “As soon as you’ve got temps getting up into the 60s consistently, that’s a great time to begin. Remember, the smaller the weeds are, the easier they are to kill. Plus, the earlier you can knock them out, that’s just one less thing to worry about as you approach planting time.”
He adds that due to the complexity of tank mixes, the variances of plant-back restrictions and how they relate to different crops, and other challenges faced by grain producers, it’s important for farmers to utilize the services provided by the agronomy professionals at Co-op and GreenPoint retail stores.
“Producers have so much to think about — commodity markets, equipment, land rents, and so on — that it can sometimes be hard to work this stuff out,” he says. “That’s a segment of the business where we have a team of experts who can carry some of that load. Budget always plays a role. For example, a grower might only have the budget for glyphosate and 2,4-D, and that’s just fine. We can help him determine the proper timing of that burndown based on the crop he’s going to follow it with. The key is making the proper choice that will result in more money in the bank at harvest.”
Tank mixes can vary due to a number of variables, including target plant species, timing and plantback restrictions, weather patterns, and budget. To develop a comprehensive burndown strategy, consult with the agronomy experts at your local Co-op or GreenPoint Ag store.
Perhaps one of the most pressing issues is spring burndown. Loosely defined, burndown is the process of eliminating weeds and cover crops prior to spring planting. A standard practice of no-till farming — which constitutes roughly 80% of Tennessee’s grain acres — burndown also helps break the “green bridge” (the transition of pests from weeds to crops) and allows the seedbed to warm up and dry out faster.
Depending on weather conditions during the winter months, burndown can begin as early as late February or early March and should be based on several variables, including crop species and variety, weather, weed pressure, plant-back restrictions, and budget.
Cullen Wiggins, Crop Protection Marketing Manager for GreenPoint Ag, says his first consideration when making burndown recommendations is the weeds that need to be controlled.
“Usually, we’re talking about three driver weeds — marestail, henbit, and Italian ryegrass,” says Wiggins. “When we’re discussing corn, we’re thinking mostly about Italian ryegrass. Mississippi State University has some great data that shows about an 8-time ROI (return on investment) on every dollar spent on controlling Italian ryegrass in corn. That tells you how important it is to get that weed killed before you put a corn seed in the ground.”
Wiggins says there is an allelopathic reaction between corn and Italian ryegrass, meaning the weed releases a chemical compound into the soil that is detrimental to the crop and negatively impacts yields.
“Because of this, it’s critical to kill that ryegrass while it’s small and before it begins to tiller in mid to late spring,” he says. “If not done in the fall, early spring is the time to address that weed if your field conditions allow. You can go ahead and put a residual herbicide in the tank mix as well to prevent any additional flushes [of ryegrass] before you get ready to plant corn.”
Because of Italian ryegrass’ resistance to glyphosate and plant back considerations with clethodim, Wiggins recommends starting with paraquat and atrazine in the tank in front of corn and then mixing with a Group 15 herbicide like WinField United’s Charger® Basic.
For marestail (or horseweed), Wiggins says, try to apply a burndown application either before or shortly after the plant bolts.
“We want to get it in that early, rosette stage,” he advises. “Glyphosate is a standard in burndown applications in Tennessee, but additional modes of actions are required to control marestail such as Sharpen®, Verdict®, or Elevore®.”
For producers who have a substantial infestation of henbit, Wiggins recommends one ounce per acre of Corteva’s Elevore® herbicide.
“That can be used in combination with glyphosate, 2,4-D, Corteva’s LeadOff ®, or a variety of other products,” he says. “And speaking of tank mix, in most cases, it will be necessary to add a good oil-based adjuvant like [WinField United] StrikeLock® to increase the efficacy of these applications.”
Regarding timing, Wiggins advises applying burndown herbicides as early as late February or the first of March.
“It all depends on the weather,” he says. “As soon as you’ve got temps getting up into the 60s consistently, that’s a great time to begin. Remember, the smaller the weeds are, the easier they are to kill. Plus, the earlier you can knock them out, that’s just one less thing to worry about as you approach planting time.”
He adds that due to the complexity of tank mixes, the variances of plant-back restrictions and how they relate to different crops, and other challenges faced by grain producers, it’s important for farmers to utilize the services provided by the agronomy professionals at Co-op and GreenPoint retail stores.
“Producers have so much to think about — commodity markets, equipment, land rents, and so on — that it can sometimes be hard to work this stuff out,” he says. “That’s a segment of the business where we have a team of experts who can carry some of that load. Budget always plays a role. For example, a grower might only have the budget for glyphosate and 2,4-D, and that’s just fine. We can help him determine the proper timing of that burndown based on the crop he’s going to follow it with. The key is making the proper choice that will result in more money in the bank at harvest.”
Tank mixes can vary due to a number of variables, including target plant species, timing and plantback restrictions, weather patterns, and budget. To develop a comprehensive burndown strategy, consult with the agronomy experts at your local Co-op or GreenPoint Ag store.