prepared by: Tom Peters, Extension Sugarbeet Agronomist, U of MN & NDSU
Delay in start to sugarbeet planting means growers targeting waterhemp as their most important weed control challenge need to reevaluate their weed control strategy.
Sugarbeet Planting Delay Means a Change in Strategy for Waterhemp Control
Delay in start to sugarbeet planting means growers targeting waterhemp as their most important weed control challenge need to reevaluate their weed control strategy. Waterhemp germinates and emerges at approximately 350 cumulative growing degree days, base 48 or approximately May 10 in west central Minnesota and May 15 in the southern Red River Valley. Sugarbeet planted on April 30 will not reach the 2-leaf stage until May 16 or after waterhemp has begun to emerge.
It means we must use a preemergence herbicide. Which one? There are three herbicide options. Strengths and weaknesses of each option included
Dual Magnum can be applied preemergence using the indemnified 24c supplemental registration available at the Syngenta website https://www.syngenta-us.com/labels/indemnified-label-search
Planting has been delayed due to wintry weather. Has the later spring delayed waterhemp emergence? Eighty percent of growing degree days for waterhemp emergence accumulate in May. There might be a 2- or 3-day delay, but that is all.
Chloroacetamide herbicides (S-metolachlor, acetochlor and dimethenamid-P) applied early post to sugarbeet and preemergence to later emerging waterhemp will follow PRE herbicides for a layer approach for weed management.
Tom Peters, Extension Sugarbeet Agronomist, NDSU & U of MN
