Get pasture weed control via dry fertilizer
Pasture managers in 17 states now can get pasture weed control as part of their dry fertilizer application.
Dow AgroSciences has issued a bulletin for these states that contains instructions for applications of dry fertilizer impregnated with GrazonNext® HL herbicide and Chaparral™ herbicide. It’s a Section 2 (ee) Product Bulletin under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA).
“For producers who use dry fertilizer, this innovation can save a trip across a pasture, save an application cost and save the trouble of calibrating a sprayer,” says Jillian Schmiedt, Dow AgroSciences Range and Pasture product manager. “Because the herbicide is part of the fertilizer granule or prill, drift is nearly eliminated.”
Many ranchers and custom applicators blend herbicide with liquid fertilizer to be applied on pastures and grass hayfields. But, until recently, only Texas and Oklahoma were included in the bulletin allowing herbicide impregnation onto dry fertilizer.
Now, Dow AgroSciences has issued the bulletin for 15 other states. As of late 2017, GrazonNext HL and Chaparral can be impregnated onto dry fertilizer in Alabama, Arkansas, Florida, Georgia, Iowa, Kansas, Kentucky, Louisiana, Mississippi, Missouri, Nebraska, Oklahoma, Oregon, South Dakota, Tennessee, Texas and Washington.
How it works
Impregnating fertilizer with GrazonNext® HL or Chaparral™ herbicide is a simple process for the herbicide retailer. Herbicide in a concentrated solution is sprayed on the dry fertilizer granules or prills during the blending process.
To get an adequate dose of herbicide properly distributed, the herbicide should be applied with at least 200 pounds of dry fertilizer per acre.
Operators of spreader trucks or fertilizer buggies then apply the treated fertilizer as they would normally.
From there, rainfall puts the herbicide-fertilizer mixture into the soil. Weed control is almost entirely dependent on the soil residual activity of the herbicide and root uptake by the weeds. For that reason, weed control from impregnated fertilizer may be less than it would be from liquid, foliar applications that work through both leaves and soil activity, say Dow AgroSciences Range & Pasture experts. Control also may be slower.
In practice, however, many users report weed control comparable to that from liquid applications.
Precautions and restrictions
Chaparral™ is not recommended for use in bahiagrass pastures or in pastures seeded with ryegrass. Chaparral in a liquid, foliar treatment can be used to control Pensacola bahiagrass and ryegrass, so injury to those species is possible from dry fertilizer impregnated with Chaparral.
Dow AgroSciences requires dedicated equipment for herbicide-impregnated fertilizer — to be used on pasture and nothing else — to avoid potential for the herbicide to be spread onto sensitive crops. Adding a dye alerts users to the presence of the herbicide. The dye also makes it easier for the retailer and customer to tell how well it’s blended.
Review this fact sheet to learn more about impregnating dry fertilizer with GrazonNext HL or Chaparral herbicides. And then contact your fertilizer retailer, ag chem dealer or Dow AgroSciences Range & Pasture Specialist.
®™DOW Diamond, GrazonNext and Chaparral are trademarks of The Dow Chemical Company (“Dow”) or an affiliated company of Dow.
GrazonNext and Chaparral are not registered for sale or use in all states. Contact your state pesticide regulatory agency to determine if a product is registered for sale or use in your state. Both products are labeled for fertilizer impregnation in the states of AL, AR, FL, GA, IA, KS, KY, LA, MO, MS, NE, OK, OR, SD, TN, TX and WA. Always read and follow label directions.