Peak + dicamba, applied postemergence, provides excellent control of wild carrot in corn (2 of 2).

Based on research conducted in Ontario, the most effective herbicide applied postemergence in corn for the control of wild carrot is Peak + dicamba (1 of 2).

Based on research conducted in Ontario, if corn has emerged, many of the Group 27 herbicides applied postemergence provide good/excellent control of waterhemp (assuming it is not Group 27 resistant waterhemp).

Based on research conduced in Ontario, 2,4-D applied preplant controlled glyphosate-resistant Canada fleabane 56%. In E3 soybean, the addition of Eragon to Enlist Duo improved control to 94%.

Based on research conducted in Ontario, dicamba applied preplant provides variable control of glyphosate-resistant Canada fleabane in XtendFlex soybean. Control is improved by increasing dicamba rate; however, control is the best with the addition of Eragon.

Based on research conducted in Ontario, Eragon provides variable control of glyphosate-resistant Canada fleabane. The tankmix partner that provides the most consistent control is metrbuzin (Sencor).

Mike Cowbrough, Darren Robinson, Peter Sikkema, Josh Skelton, and Tom Wolf will be presenting the Weed Science Short Course - Eastern Canada during the week of November 18-22 in London, ON. Please go weedscienceshortcourse to register.

The Weed Science Short Course will be offered during the week of Nov. 18-22 in London, ON and the week of Jan. 27-31 in Winnipeg, MB. Please go to https://t.co/DshSgbbFbf to register.

These pictures are from the same location in a commercial corn field. Assuming the weeds were 3" at application, and with this density, Ontario research predicts a yield loss of 10.8 bu/ac. At $6.32/bu that would be a loss $68/ac. Timing of weed control affects profitability!

The weed control benefits of adding the correct adjuvant to a herbicide are well documented; weed control can be improved dramatically. However, the addition of too many spray additives can result in unacceptable crop injury.

With the very frequent rain events in 2024, postemergence herbicides in soybean may be delayed. In high density weed environments where no soil-applied herbicide was applied there was a loss of $26/acre when first postemergence herbicide was applied when weeds were 2" in height

With the very frequent rain events in 2024, postemergence herbicides in soybean may be delayed. In high density weed environments where no soil-applied herbicide was applied, yield loss can be rapid. Loss of 2 bu/ac if first herbicide is applied when weeds are 2" in height

With the very frequent rain events in ON, Canada in 2024, postemergence herbicides in corn may be delayed. In high density weed environments where no soil-applied herbicide was applied, monetary loss can be rapid and increases on a daily basis (n=7).

With postemergence only weed control programs in high density environments, corn yield is reduced 4, 15, 27, and 39 bu/ac when the first herbicide application is applied 7, 14, 21, and 28 days after corn emergence, respectively (n=7).

Based on 4 trials in Ontario, Roundup (0.67 L/ac) controlled annual ryegrass 82%. The addition of a Group 2 herbicide (Elim, Ultim, Accent, or Option) improved control to 91-94%.

Roundup (1.0 L/ac) controlled annual ryegrass 72% based on 4 trials in Ontario. The addition of a Group 1 herbicide increased control marginally to 78-84%. Roundup + Eragon controlled annual rye grass 79%.

Control of annual ryegrass with glyphosate applied in the spring is influenced by rate. Based on 4 trials conducted in Ontario, Roundup applied at 0.33, 0.67. 1.0, 1.33, and 2.0 L/ac controlled ryegrass 44, 63, 72, 80, and 90%, respectively.

Based on six trials conducted in Ontario, Canada with herbicides applied in the fall after winter wheat emergence to emerged MHR Canada fleabane control the following year prior to combining was Infinity (80%), Infinity FX (85%), and Pixxaro M (94%). Wheat yields were similar.

The benefit of adding Class Act NG to Roundup is influenced by the rate of Roundup. With Roundup at 0.33 L/ac there is an increase in corn yield of 15 bu/ac; no increase in corn yield with Roundup at 0.67 or 1.0 L/ac. (4 of 4)

The benefit of adding Class Act NG to Roundup is influenced by the rate of Roundup. With Roundup at 1.0 L/ac there is no statistically significant increase in weed control. (3 of 4)