Source: Bayer CropScience

This spring, Extension weed scientists across the country recommend that growers use an early-season herbicide with residual in order to get a jump on weeds and protect their corn crops.

In fact, that's the standard recommendation weed scientists make each year. But it's particularly sound advice for 2010, given the wild weather swings the past two years, when unpredictable weather prevented many corn growers from addressing weed problems in a timely fashion with post products.

"Beyond simply giving you a head start on weed control, an early-season herbicide application means you are protecting corn yield potential at your earliest opportunity," said Jeff Springsteen, Bayer CropScience marketing manager for selective corn and soybean herbicides.

The company offers corn growers a complete portfolio of products for grass and broadleaf weed control, including Balance Flexx pre-emergence corn herbicide, which prevents yield loss due to early-season weeds. It also reactivates, with just a half-inch of rain, to kill late-emerging weeds.

Balance Flexx contains the exclusive Crop Safety Innovation (CSI) Safener, enabling it to be used on any soil type, from pre-plant to the two-leaf collar growth stage (V2). While protecting the plant from herbicide injury, the CSI Safener also has been shown to result in increased root growth and plant health.

"Crop response was always a fear of ours with Balance Pro, but we're more confident in Balance Flexx because of its safener," said Gerrit Thompson, crop consultant with Crop Production Service, Roachdale, Ind. "Plus, we can apply it on up to two leaf-collar corn. That's a nice benefit."

Research by Iowa State University (ISU) in 2008 documented a 10 percent yield loss as early as the V2 corn growth stage due to weed competition. In addition, ISU and University of Wisconsin (UW) research indicates that significant corn yield is lost if weeds are allowed to grow above 4 inches in height.

In fact, if weed pressure is considered heavy (10 or more weeds per square foot), ISU research recommends applying control measures before the weeds exceed 2 inches in height.

"That early treatment timeframe is important, as it minimizes the opportunity for weeds to emerge and compete with corn for valuable nutrients and moisture," Springsteen said. "It can really pay to prevent weeds from becoming a problem."

Balance Flexx controls some of the toughest weeds corn growers face, including kochia, woolly cupgrass, marestail, common ragweed and barnyardgrass. Flexible enough to fit any tillage program, Balance Flexx works through the roots and shoots of weeds to provide excellent burndown and residual control.