Out-of-Crop Weed Control - Managing Difficult Weeds

Spray out-of-crop to control hard-to-kill weeds.

Out-of-crop weed control can be one of your most important strategies in managing difficult weeds. Whether you choose to do pre-seed, chem-fallow or post-harvest applications, choosing the right herbicides can keep weeds from robbing soil moisture and nutrients.  

Use a Glyphosate Add-in When Spraying Out-of-crop

No matter how much glyphosate you use, there are weeds that it won’t effectively control alone. Volunteer glyphosate-tolerant canola is an obvious problem, but you’ve likely also noticed how hard it is to get good control on dandelion, narrow-leaved hawk’s-beard and flixweed too.

Use Proper Timing for the Toughest Invasive Weeds

Dandelion is one of the toughest weeds to control. It’s best if the herbicide is translocated down into the root system along with sugars. That happens in the fall. Add a herbicide with glyphosate to improve dandelion control, and you’ll help control winter annuals as well.

Spring-germinating volunteer canola needs to be controlled early in the spring. Of course you’ll need to add a herbicide from a different group than glyphosate to control Roundup Ready® canola.

Wild buckwheat is a spring germinator. Control it in a pre-seed burn-off or in-crop. It’s a weed that has always had more tolerance to glyphosate than other weeds. Control it when it’s small.

Flixweed is best controlled in October with a post-harvest application. You can still control it quite easily with a pre-seed burn-off in the spring. But left to later spring applications it can remove a lot of moisture. Catching flixweed in the rosette stage prior to bolting provides the most effective control.

Narrow-leaved hawk’s-beard (NLHB) should be controlled post-harvest. By the time you get into the spring, NLHB can be tough to control, especially if the weed starts to bolt and gets over 2 inches high. Once bolted it’s much more difficult to control.



Dandelion will translocate herbicide into its root system if controlled at the right time.
Volunteer Canola

Volunteer Canola

Spring-germinating volunteer canola needs to be controlled early in the spring, before it robs soil nutrients and moisture.
Wild buckwheat

Wild Buckwheat

Wild buckwheat is a spring germinator. Control it in a burn-off or in-crop.
Flixweed control


Improve flixweed control in October with a post-harvest application.
Narrow-leaved Hawk’s-beard (NLHB)

Narrow-leaved Hawk’s-beard (NLHB)

A post-harvest application is the best time to control narrow-leaved hawk’s-beard.

Roundup Ready® is a registered trademark of Monsanto Company.

The information provided on this website is for reference only. Always refer to the product labels for complete details and directions for use.