Flipping through the Crop Protection Guide, a farmer gets the impression that there are lots of Group 1 herbicides for controlling grassy weeds in cereal crops. In fact, there were 29 brand names of this type of herbicide listed in the 2011 Alberta Crop Protection Guide (the blue book). Unfortunately, most of these products are either co-packs or generic copies of just four different Group 1 active ingredients.
to maintain a good chemistry rotation and prevent the development of weed resistance, farmers need to know the active ingredient in a product, not just the brand name. This is especially important with Group 1 grassy products. There are thousands of cases of confirmed wild oat resistance to Group 1s. Between four and 10 million acres in Western Canada have Group 1 resistant wild oats.
With so many generics on the market, it’s becoming increasingly important to know your actives. Farmers may believe they’re using a new product when they choose a chemical with a different name, but the new chemical may have exactly the same active ingredient as the one that was used last year.
Another consideration is the increase in multi-group products. A product listed as Group 2 and Group 4 may have the same Group 2 active you used last year for the same weed spectrum.
The following tables identify the active Group 1 ingredients in all the Group 1 grassy weed control products that are listed in the 2011 Alberta Crop Protection Guide and registered for use on the prairies. (Next year, there will likely be even more names on the list. Between July 1 and November 15, 2011, the Pest Management Regulatory Agency had already received four applications for new clodinafop propargyl herbicides.) The table also shows the registration date for each product, the manufacturer who registered each generic, as well as any other actives co-packed or preformulated in the herbicide.
Play close attention to the registrant of the generic. If the registrant of the generic is the same company that registered the original brand, there is a greater likelihood that the inert products in the generic will be the same as in the original brand name. There are four key active ingredients.
1. Clodinafop propargyl
Original product: Horizon 240EC (Syngenta) received Canadian registration April 19, 1995
There are two tables incluing this active ingredient — one on the previous page, and one on this page listing co-packs with grass and broadleaf herbicides.
Original product: Acclaim (Agrevo) received Canadian registration May 9, 1989.
Original product: Crestivo (Syngenta) received Canadian registration October 27, 2005.
Original product: Achieve DG (Syngenta) received Canadian registration March 20, 1992.
Knowing these details will assist in planning your herbicide rotations and also make it easier to compare Group 1 products on the market. †