Roundup Ready soybeans dominate the Mani toba market now, but Nufarm thinks there’s room for Valtera, a new pre-emergent soybean herbicide from U.S.-based Valent. Nufarm says it controls broadleaf weeds such as Eastern black nightshade, lamb’s quarters and pigweed – including Group 2 and triazine-resistant biotypes.
Grant Deveson, Nufarm’s commercial manager in Canada, told a meeting of reporters than U.S. demand has increased for the Group 14 herbicide with flumioxazin as the active ingredient. He predicts the same will occur here.
“Five years ago in the U.S. none of these additive products were used – it was just wall-to-wall glyphosate,” Deveson said. “What’s changed there is a lot more concern over weed resistance and management. And I think we will see the same thing happen in Canada but at a bit of a slower pace.”
Deveson said some farmers get tired of spraying their soybeans two or three times with glyphosate, which only controls weeds it comes in contact with. “(O)nce an application of glyphosate goes down there’s no residual activity and something like Valtera will bring residual activity,” Deveson said. “So you put it on in the spring and your crop will stay clean for 60 days.”
However, that residual activity also restricts farmers to only replanting soybeans in treated fields if their soybeans fail early in the season.
Winter wheat can be seeded four months after a field has been treated with Valtera, according to its label. The wait is eight months for spring wheat, nine for sunflowers, corn and canola, 11 months for alfalfa and barley and 12 months for all other crops.
Dry common beans need nine months, the label says, but adds that not all varieties have been tested. Since herbicide tolerance varies, farmers are advised to test a small area before seeding a whole field to beans the year after applying Valtera.
Valtera is more effective in controlling weeds when evenly applied to a weed-free field. Disturbing the soil can result in weeds escaping the herbicide so it’s better to seed first, but Valtera needs to be applied no later than three days following seeding.
“Application after the soybeans have begun to crack, or are emerged will result in severe crop injury,” the label says.
Moisture is required to make Valtera work. Residual weed control depends on the application rate, the amount of rainfall received and temperatures. The warmer and wetter the conditions, the shorter the residual control.
Valtera shouldn’t be used in waterlogged fields, soils with light soils or soils low in organic matter, said Nasir Shaikh, a weed specialist with Manitoba Agriculture, Foods and Rural Initiatives.
Valtera is toxic to aquatic life so field run-off should be avoided. That can be done by not applying the herbicide on steep slopes, compacted soil or clay, the label says.
“Contamination of aquatic areas as a result of run-off may be reduced by including a vegetative strip between the treated area and the edge of the water body.”
– GRANT DEVESON, NUFARM