Redroot Pigweed (Amaranthus retroflexus)
This weed shows up as the number one weed problem in South Dakota, number two weed problem in Colorado and the third worst weed problem in Minnesota and Manitoba. This weed has an extended germination period, is noted for its rapid growth and its high rate of seed production. There are a number of options for control.
1. Good control of RR Pigweed in previous crop
2. Use burn down up to emergence
3. Spartan has excellent control and can be used in reduced and no tillage systems
4. Beyond¹ and Express² have excellent control in post-emergence
5. Sonalan and Prowl are rated as fair to good
6. Eptam is rated as good
7. Trifluralin and Dual Magnum are rated as fair
8. Between row cultivation or between row hooded sprayer herbicide application
Colorado Weed Management Guide (link)
Glyphosate, Weeds, and Crops (link)
KSU Weed Publications (link)
NDSU Crop Production and Marketing (link)
SDSU Weed Control in Oilseed Crops (link)
Sunflower labeled Herbicides (link)
Contact the chemical companies to obtain a copy of the label.
(1) Beyond herbicide is specific to CLEARFIELD® hybrids only. Clearfield hybrids have been developed with a resistant gene to Beyond herbicide. Applying Beyond herbicide on non-Clearfield hybrids will result in extensive damage.
(2) Express herbicide is specific to ExpressSun® hybrids only. ExpressSun hybrids have been developed with a resistant gene to Express herbicide. Applying Express herbicide on non-ExpressSun hybrids will result in extensive damage.
Glyphosate and Aim are labeled for between row hooded sprayer applications.