When herbicides just won’t kill your weeds anymore — and the cost of multiple herbicide applications is no longer economical — what do you do?

It’s a predicament more no-tillers in the Great Plains and out west are facing. Kansas alone has 26 unique resistant weeds, according to the International Survey of Herbicide Resistant Weeds. Species like kochia and Palmer amaranth are resistant to multiple herbicide modes of action.

To get a handle on these weeds, some no-tillers are turning to undercutters. With V-shaped blades, this minimum tillage tool cuts horizontally a few inches below the soil surface, severing weed roots without turning over the soil. 

While controversial, as it does disturb the soil, undercutting may help no-tillers get stubborn herbicide-resistant weeds under control, without sacrificing all of the soil health benefits of no-till.

Complete Control

In the drylands of the Pacific Northwest, Russian thistle is a persistent problem in spring wheat. To see how effective undercutting is at controlling the broadleaf weed compared to herbicides, Washington State University researchers conducted a study from 2000-06 that compared both treatments post-harvest in continuous annual spring wheat.

For the undercutting treatment, researchers used a Haybuster 3200 undercutter at a 3-inch depth one week after spring wheat harvest. They noted that unlike traditional sweep implements, the Haybuster 3200 has wide, narrow-pitch, overlapping V-blades that slice through the soil with minimum lifting and stirring.

SLICING WHILE PRESERVING. The Haybuster 3200 undercutter has 32-inch blades on 28-inch spacing, leaving no room for a weed to…