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Resist herbicide resistance with prudent treatments, cover crops, rotations

The news of growing herbicide resistance in big species like
waterhemp and Palmer amaranth is spawning a lot of talk about the
different ways you can prevent resistance, both naturally or through
herbicide. So, what's your preferred way to avoid herbicide resistance
in your fields?

Ed Winkle's seen first-hand the problem resistant weeds can pose. The Martinsville, Ohio, farmer, certified crop adviser and Agriculture.com Crop Tech Tour correspondent
just returned from a trip around the mid-South, where resistant Palmer
amaranth bas become a "huge problem." Upon returning to his area, Winkle
examined his own plans for weed control without resistance.

"We
have to be careful not to ruin herbicide trying to save Roundup Ready
crops. It all makes me happy I have stayed with non-GMO corn and
switched back to non-GMO soybeans for a more total weed control
solution," Winkle says. "We have weeds and we have too many resistant
weeds!"

Winkle also has cover crops on his rotation roster,
something other farmers say don't fit as well with their cropping
systems. "While we all like the cover crops for tons of reasons, we
never get enough fall growth for them to keep the winter annuals out of
the field," says Arcadia, Indiana, farmer Ken Rulon.
"So, a spring 2,4-D application is required. Actually, our worst
marestail problems have come in fields where we had the best cover
planted in early September. I think the planter helped seed them in."

It's
the time crunch for getting cover crops sown among all other fieldwork,
as well as a lack of results thus far, that is keeping Macon, Illinois,
farmer Paul Butler from implementing cover crops on a large scale on his farm yet.

"2,4-D
is stocked in the shed ready for fall spray -- just like it was last
year when we finished harvest on December 5. I hope to put it on every
acre this year," Butler says. "I am not seeing the benefits [of cover
crops] here yet. Still experimenting. Tried radishes, but have got to
seed earlier. Tried rye -- looked good but didn't show any difference on
the yield monitor. Long story short, I've got to see results on small
scale before I can invest money on larger scale (meaning buy a drill)."

Though
this year's shaping up differently than last year's drawn-out, late
harvest, Butler adds it's tough enough to get harvest and fall
fertilizer applications completed before winter sets in, and at this
point, fall spraying and cover crops rank 3rd and 4th on his fall
priority list, respectively.

Whatever you plan to do to attack
weeds and possible herbicide resistance in your fields, Winkle says it's
important to have a plan in place, one that can be carried out under
time constraints like Butler's facing. And, don't rule out other field
operations in how they might contribute to resistance.

"Every
farmer needs to think out a plan like you have. I know we all need to
use more residual chemical and quit putting so much pressure on a few
good chemicals. 2,4-D is an important tool in that toolbox," he says. "I
noticed volunteer beans in the wheat and even more marestail disturbed
by the drill, right in drill paths. A good job of combining and
excellent residue spreading is a must for more reasons than reducing
resistant weeds."

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