Soybean School: Weed control strategies for a late fall


As the growing season winds down, fall provides a critical opportunity for weed management — especially in those soybean fields that are a bit behind in the maturity game.

As Ken Currah of BASF explains in our latest episode of the Soybean School, this time of the year the focus is going to be on perennial weeds — such as thistles — that are pulling nutrients into their extensive root systems.

“Fall is a great time to hit the emergence and establishment window of some weed species,” he explains. “But for some perennials, it allows us to catch them when they’re getting ready for winter.” (Story continues below video)

One challenge when it comes to fall weed control is the shorter daylight hours, which makes it more difficult for herbicides to work to their full capabilities. Currah notes that in fall, we can send herbicides for the ride, with nutrients moving to the roots, and “really start to set ourselves up for some actual weed control — as in removal from the field.”

Left unchecked, problem perennials like thistles can form extensive root systems that are much more difficult to control in spring. In order to stay on top of it, it’s going to require knowing your field inside and out, and knowing exactly where and what those problem areas are.

“You’ve also got to know how [the problem weed] fits into your spring herbicide program as well,” explains Currah. For growers facing late harvests, optimizing the post-harvest weed control pass becomes even more crucial. However, it’s important to note that crucial doesn’t mean get it done as fast as you can — speed really matters for efficacy, here.

“If you slow down, you will get better coverage, there’s less turbulence behind the boom, and you’ll get better coverage on that crop,” says Currah. “Cleaning up problem perennials in the fall, growers set themselves up for better spring control.”

Wake up with RealAgriculture

Subscribe to our daily newsletters to keep you up-to-date with our latest coverage every morning.

Wake up with RealAgriculture

Other Episodes

Soybean School (view all)Season 12 (2023) Episode 5

Please register to read and comment.


Register for a RealAgriculture account to manage your Shortcut menu instead of the default.