By Pamela Smith
DTN/The Progressive Farmer Crops Technology Editor
BLUE MOUND, Ill. (DTN) -- It's 7 a.m. and the pile of shoes and water jugs sitting outside Amy Brown's back door tell a tale. Inside the white farmhouse, teenagers cover the carpet and sprawl across sofas, soaking up the last few gasps of air conditioning before heading to the soybean field.
The central Illinois humidity already hangs heavy in the air. A few frisky boys shoot hoops as they wait for stragglers that are apt to arrive still wiping sleep from their eyes.
Brown, a Blue Mound, Illinois, farmer, farm wife and mother turned bean-walking crew leader this summer. Some local farmers enlisted her help in hopes hand labor can tackle weedy infestations of waterhemp in fields where modern-day herbicides have failed.
Twenty years ago, walking beans was a summer ritual for teens. Midwest farm kids often took to fields with hand tools to subdue weeds such as velvetleaf, volunteer corn, cocklebur and an occasional milkweed. Then, genetic engineering and tolerance to glyphosate ushered in an era that made hoes and those who wielded them as necessary as buggy whips.
Weeds are getting the last word, though. Southern farmers began hiring hoe crews several years ago as a last-ditch effort to battle back against herbicide-resistant Palmer amaranth, an obnoxious cousin to waterhemp. However, the practice of hand weeding broad-acre crops is retro enough in mid-America that cars still slow as drivers puzzle over the sight.
"Walk and chop. Walk and chop as you talk," Brown urged workers this past Saturday. A perky blonde with a cheerleader-like personality, Brown's first-round draft choices for the chore included sons, Marshall and Walker. They recruited a surprisingly strong lineup of a dozen or more classmates (who also happen to be teammates on the Meridian High School football team). The signing bonus this season has been running around $10 per hour.
Brown's crew found themselves wading through soybeans up to their armpits and whacking away at waterhemp -- and some marestail -- that was both impressive in volume and size.
University of Illinois weed specialist Aaron Hager said waterhemp is a relatively shade-tolerant species and those towering above the crop this time of the year might have emerged prior to the soybean canopy closing the rows. "It simply takes some time for those plants to break above the canopy," he said.
The erratic weather of the 2015 season also allowed the weed to gain more of a foothold. "Abundant rainfall kept many growers from making timely post [herbicide] applications, even in fields treated with residual herbicides close to planting," Hager said. "By the time they were sprayed, some waterhemp were simply too large to be effectively controlled."
Pete Pistorius, a Blue Mound, Illinois, farmer had 160 acres that fits that scenario. He was one of the local farmers who hired Brown's crew. He also put several of his own employees in the field to help chop.
Pistorius applied a full rate of Optill Pro before planting and followed with 44 ounces of glyphosate and 12 ounces of Cobra. Despite the use of a pre-program, he experienced what other farmers have also noticed this season -- soybean fields with near-perfect control lined up next to a few fields weedy enough for Pistorius to deem them "a train wreck." The fields were sprayed the same day with the same herbicide program from the same herbicide tanker.
Hager said this season's waterhemp infestations are serving up reminders that each field, whether adjacent or a quarter-mile away, are unique biological systems. "Just because a treatment works in one field does not guarantee that [herbicide] resistance hasn't evolved in the other field," he said.
That further complicates weed-control decisions for farmers who still remember the simplicity of Roundup Ready (glyphosate) technology before some weeds began to outsmart it. Waterhemp in Illinois now has the ability to resist five different herbicide families (glyphosate, HPPD-inhibitors, PPO-inhibitors, PS II-inhibitors, ALS-inhibitors). Waterhemp has also shown the ability to resist Group 4 herbicides (2,4-D) in Nebraska, and official confirmation is pending in Missouri and Illinois. Weed populations with resistance to multiple herbicide classes are increasingly common, leaving few control options, particularly in soybeans.
Adding hand rouging to weed-control costs brought Pistorius' total 2015 control costs on those weedy 160 acres to nearly $100 per acre. That's a pinch Southern growers attempting to manage weed resistance have already felt, but an expenditure that leaves most Midwestern farmers gasping. Still, chopping weeds to keep weed seed from the soil seed bank is a preventative step Pistorius hopes will pay off next season.
Hager said hand removal of weeds could make a difference if female plants are eliminated before seeds begin to turn brown and become viable. He reminds growers that combines can spread weed seed. Growers that haven't taken measures to control weed breaks should harvest contaminated fields last, he said.
Brown has already alerted her high school weed team that positions on the chopping crew will likely be available again next summer. Palmer amaranth, an even bigger weed worry, was recently discovered growing in a field near those the crew cleared.
For a refresher course on how to identify waterhemp and Palmer amaranth, go to: http://bulletin.ipm.illinois.edu/…
For more information on waterhemp management: http://takeactiononweeds.com/…
Pamela Smith can be reached at Pamela.smith@dtn.com
(AG/CZ)
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