You Planned for Lay-By Treatment in Sugarbeet? Consider a Preemergence Application. (05/13/21)
We often plan our weed management strategies during winter meetings or in brain-storming meetings around the coffee pot. The Sugarbeet Agriculturalists and I agreed we would introduce a split lay-by program for waterhemp control in districts in northern North Dakota and Minnesota or districts with no current experience with either soil residual products or waterhemp in 2021. Split-layby means an application of a chloroacetamide herbicide once sugarbeet are at the 2-lf stage and preemergence to waterhemp followed by a repeat application approximately 18 days later or once sugarbeet reach approximately the 6-lf stage. We planned to time the first lay-by application around May 15.
Reality has set in and we have very few emerged beets especially north of Minnesota highway 200 and rainfall has been nonexistent to incorporate herbicide into soil. However, the calendar date indicates we need to prepare for waterhemp emergence which is right around the corner. Can we afford to wait until 2-lf sugarbeet? Do we need to consider a Plan B?
I discussed waterhemp control this week with Kevin Hollands, Crop Consultant, CENTROL Consulting near Fisher MN. Kevin supports producers in the East Grand Forks, Fisher, and Crookston corridor or along US 2. Kevin suggested taking the layby approach and implementing it preemergence. That is, applying a chloroacetamide herbicide on beets that have not emerged using the layby rates. Dual Magnum is the only chloroacetamide that can be used preemergence and it is normally applied at 8 to 12 fl oz/A using a 24c local needs label in sugarbeet. Kevin suggested the 16 fl oz/A rate, mostly because of calendar date.
I support Kevin’s recommendation. We reduce the Dual Magnum rate in mid-April when it is cold and wet to minimize sugarbeet injury. Sure, it’s still cold but it certainly isn’t wet and my calendar says May 12. I trust we will ‘hook a rain’ in the next 5 to 7 days to incorporate product so that it is available at waterhemp emergence. We can decide waterhemp control in-season later.
Extension Sugarbeet Agronomist
NDSU & U of MN