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What Will Weed Resistance Cost You This Year?

What Will Weed Resistance Cost You This Year?

02 April 2013

ANALYSIS - For farmers in the northern hemisphere, it’s about time for planters to start rolling. While seed decisions were likely made months ago, herbicide decisions are usually a wait-and-see prospect depending on what type of spring Mother Nature graces us with, writes Sarah Mikesell, TheCropSite senior editor.

Jeff Springsteen, Senior Product Manager - Herbicides, explains the economics of weed resistance in areas where resistance is already an issue and also for areas which are just starting to see signs of trouble.

In the US, herbicide costs in the PRE-weed resistance days were about $10-20/acre, said Springsteen. Now Midwest soybean growers are paying $30-40 per acre in areas where herbicides aren’t working as well. However, if you move down into the southern states, they are spending anywhere from $70-120 per acre to get sufficient weed control.

A portion of that high cost to southern growers is due to the use hand-hoeing crews, who come in to cut down weeds during the growing season so the millions and millions of seeds for next year’s “weed crop” don’t scatter during the autumn.

Resistant weeds are definitely on the move. The dreaded resistant Palmer amaranth is even leaping north to areas in Michigan and Wisconsin due to feed that’s being transported north to dairy farms.

Rotating your crops isn’t enough. Today, your best solution is to rotate your chemistry and use multiple modes of action, said Springsteen.

Here are a few tips from the Bayer CropScience Respect the Rotation campaign:

  • Know Your Weeds. Know Your Fields - Identifying weed species will help pinpoint which herbicide program will work best on every acre. Also understand the weed pressure and history within each field.
  • Start Clean - Effective tillage or the use of a burndown herbicide program can control emerged weeds prior to planting.
  • Stay Clean. Use Overlapping Residuals - In any weed management program, the goal should be to control at least 80 percent of the weed population with residual herbicides.
  • Apply Herbicides Correctly - Apply to actively growing weeds. Apply when weeds are no more than 3 to 4 inches. ALWAYS Follow label instructions.
  • Do Not Allow Weed Escapes - Treat every weed escape as if it is a resistant weed. Consider spot herbicide applications, row wicking, cultivation, hand removal of weeds and other techniques to stop seed production.
  • Zero Tolerance to Reduce the Seed Bank - Do not allow surviving weeds to set seed in order to decrease weed population shifts from year to year and prevent major weed shifts. OnePalmer amaranth plant can produce up to 1 million seeds per plant in optimal conditions.
  • Clean Equipment - Avoid moving equipment that has not been thoroughly cleaned.

Bottomline: weed resistance is not going away. And US farmers – don’t think you are alone. This is a global issue. Weed resistance is on the move and growing.

Sarah Mikesell, Senior Editor

Sarah Mikesell, Senior Editor

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