Expanded Acetochlor Crop Rotation Options

Chris Boerboom, Extension Weed Scientist

Dow recently received EPA approval on a series of acetochlor supplemental labels that expand crop rotation options.  Previously, corn could be planted anytime after a Surpass or TopNotch application; soybean, sorghum, and tobacco could be planted the following spring; and wheat could be planted after 4 months.  The new Surpass and TopNotch supplemental labels (available on cdms.net) also allow alfalfa, barley, oats, rye, potatoes, and dry beans to be planted as rotational crops the spring following an application.  Some other crops not common to Wisconsin are also rotational options.  Snap beans and green peas are not allowed as rotational crops. 

Supplemental labels for Dow’s acetochlor plus atrazine premix herbicides (FulTime, Keystone, Keystone LA) allow for rotations to soybean, sorghum, and tobacco the following spring and wheat after 15 months as previously labeled.  These herbicide labels now allow for rotation to alfalfa, barley, oats, rye, and potatoes 15 months after application.  In most cases, this realistically means a 2-year rotational interval for these crops except it would allow for fall seeding of alfalfa, wheat, or rye in the fall after a rotational crop was grown.  For instance, if Keystone LA was used in field corn and rotated to sweet corn the next year.  Alfalfa or wheat could be seeded after sweet corn harvest.