The Dangerous Weed Question You Should Never Ask

The Dangerous Weed Question You Should Never Ask

Generally, asking questions can help you hone your management practices and become a better farmer. But when it comes to weed control, one question in particular is best left unasked, according to Ryan Rector, Roundup technology development manager at Monsanto.

“Can I get away with …? – that’s a dangerous question,” Rector says. “Cutting rates and a lack of tankmixes and residuals helped get us to where we’re at today.”

Research has shown that a two-pass herbicide system with a residual up-front leads to fewer weeds and higher yields when compared to a single-pass system, Rector says. He highlights five best practices farmers should consider in their weed programs.

  1. Tillage or burndown prior to planting.
  2. Using a residual herbicide in the first pass.
  3. Including a post application with herbicides that have multiple sites of action.
  4. Scouting after every application. “If we didn’t control a weed, we want to know why, and we want to know what to do next,” Rector says.
  5. Spraying weeds when they are 4” or smaller.

Even when next-generation traits that will allow over-the-top use of dicamba or 2,4-D come onto the market over the next several years, these weed control fundamentals should not change, Rector says.

“New technology will bring another tool, but the overall recommendations will not change,” he says. “Residuals and tankmixing will still be a part of the mix.”

According to a recent survey conducted by DuPont Crop Protection, 87% of farmers say they are doing everything they can to prevent weed resistance on their farms. That’s up from 70% reporting that intention in a similar survey from 2011.

Of the respondents, 61% say they plan to increase herbicide investment (defined as time and/or money spent on a herbicide program). Only 3% say they will take a “wait and see” approach as the season unfolds.

“Weed resistance management is increasingly complicated, as weeds continue to evolve,” says James Hay, DuPont business director. “A season-long weed-control plan, including herbicides using multiple modes of action, is critical to triumphing over hard-to-control weeds and protecting yield.”

Of the farmers surveyed, none say they will “significantly” decrease crop-protection inputs for 2015.

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Spell Check

Olney, IL
4/19/2015 08:45 AM

  If chemical companies want farmers to continue to use residual herbicides instead of just relying on a product to clean up the mess afterwards, the price needs to come down on those products. In the 1990's why would someone use a residual program costing $20/acre when they could just use roundup at $3/acre later to clean up their fields?


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