Corn is commonly described as a diva. It will probably thrive in the fitting conditions, however it doesn’t like competitors.
And that’s particularly evident when corn vegetation should compete with weeds for moisture in dry conditions, as seen in Western Canada and the Northern Plains of the U.S. in 2021.
“There have been many studies done, including [Peter] Sikkema’s work from eastern Canada talking about a 50 per cent yield reduction from competition from weeds early in the season. We have that critical weed-free period where we want to protect the crop, up to the six-leaf stage in corn,” explains Harold Brown, technical companies specialist with BASF in japanese Manitoba, in the video under.
The impression of early season weed control on corn in a drought is clear, each in plant measurement and yield potential, as Brown hosts us at a plot close to Winkler, Man. for this Corn College episode.
Brown compares three herbicide remedies: an untreated examine, corn that obtained pre-emerge glyphosate adopted by an in-crop glyphosate software, and corn that obtained a pre-emerge residual/glyphosate tank combine adopted by an in-crop glyphosate software.
“There are definite differences there, not just with the weed control…but you’ll also look at the effect on the corn,” he notes. “The treatment with the residual prior to emergence is the tallest, most robust, healthiest-looking corn here.”
From a rotational perspective, corn additionally gives a chance to diversify chemistries used for weed control, provides Brown.
“This is an excellent opportunity because we have a wide range of herbicides you can use with a wide range of modes of action, and we talk about multiple modes of effective action, so you can utilize Groups 5, 14, 15, 27, along with your glyphosate,” he says.
“You can have multiple modes that are effective on some of those critical weeds, for example, glyphosate-resistant kochia, volunteer canola that is resistant to different groups, and other challenging weeds, such as waterhemp, which we recently found another population of in Manitoba, most of which is glyphosate-resistant. These are all weeds we need to stay ahead of.”
Take a look at the video under for extra on the significance of early season weed control in a dry yr with Harold Brown of BASF: