Many producers in Eastern Canada have moved to no-till soybeans. There are all kinds of economic and yield benefits, not including the benefits to the environment.
But some weeds thrive in a no-till environment, like dandelion. It has a deep taproot that, once established, anchors it to the ground and makes it a formidable foe.
That’s the situation Wayne Campbell faced. He farms in northern Huron County in Ontario. He’s a committed no-tiller but he needed to find a solution to his dandelion problem.
The problem
“We no-till soybeans and we zone-till corn but even with zone-till the dandelions and sow thistle won’t be killed,” says Campbell. “If you don’t keep the pressure up on those weeds they’ll start pressuring you.”
Campbell follows no-till soybean ground in rotation with white beans and there’s no tillage until just prior to planting. Any carryover in weeds from the soybean year will show up in the edibles.
“It’s not what you want – you have to stop the sequence sometime or it just keeps getting worse,” says Campbell. “Dandelions are an ongoing problem with the amount of seedlings they produce. And you have to take every chance you can against sow thistle because one application isn’t going to get rid of it.”
But now that he’s taken most of the tillage out of his rotation, Campbell has to find another way to control dandelions.
The solution
For everything from no-till to min-till to vertical tillage, an inexpensive pre-plant glyphosate treatment provides valuable control of perennials and winter annuals that may be present. Adding residual herbicides at the same time extends the weed-free period and can eliminate a second pass with the sprayer in some cases.
“I see a lot of growers using Guardian® in a tank-mix with Boundary®,” says Mike Cowbrough, weed specialist with the Ontario Ministry of Agriculture, Food and Rural Affairs. “Both options offer a burndown and residual control. Guardian® is really showing strong performance in keeping dandelion at bay for extended periods, even into the following spring which is really beneficial for growers who no-till wheat directly into IP soybean stubble.”
“Guardian® has really good activity on dandelions and sow thistle,” says Campbell. “I like the residual on the dandelion seedlings too. We notice cleaner fields the following year when we use Guardian®.”
An added benefit
Another reason Campbell uses Guardian® is to sharpen up the broadleaf weed control. “It seems to do that in a pre-emerge application,” he says. “I guess we’re adding some cost to the burndown but we feel we’re getting better overall weed control plus adding in the perenenial sow thistle and dandelion. We’re putting most of the value to that year’s soybean crop but we also put some against the following year’s crop.”
