New Farming Technique Eradicates Weeds Without Pesticides

Industrial farming has always had one advantage over organic farming. With pesticides, you can kill just about anything and always expect higher yields and a greater shelf life. Granted, you can get some pretty impressive yields with organic farming, but it usually takes a lot more work, which often contributes to the higher costs of organic food.

But as demand for real food continues to grow, people are starting to innovate. Just like any other product, the more expensive it is, the more people will try to figure out new ways to bring the costs down, and deliver their products to a larger customer base. The latest and greatest innovation in organic farming has come from Frank Forcella, a researcher with the USDA, and it stands to make weed killing a piece of cake for an industry that isn’t allowed to use pesticides.

The tactic is gaining attention from organic farmers who don’t use chemicals and from food companies seeking to market pesticide-free snacks and other products.

Forcella said the technology is experimental but shows promise. It uses an air compressor to spray gritty material on both sides of a crop that kills young weeds without harming corn or soybeans.

“It obliterates the weed, especially if it’s a small broad-leaved weed like Lamb’s quarters or pigweed that’s one to 3 inches high,” Forcella said. “The corn plants growing next to them are taller and thicker and can withstand the grit blast, but the weeds just disappear.”

Forcella uses mainly dried corncob bits but has had similar success with other gritty textures such as ground walnut shells, corn gluten meal and soybean meal. He and others from USDA’s Agricultural Research Service have been working on organically certified plots owned by the University of Minnesota at its West Central Research and Outreach Center in Morris.

Initially, Forcella used an air compressor mounted on an all-terrain vehicle and sprayed the rows by hand. Collaboration with an engineer at South Dakota State University has now yielded a unit mounted on a tractor that blasts the weeds four rows at a time from eight nozzles. High-speed particles of grit shred the weeds at 100 pounds per square inch of compressed air.

Granted, blasting your crops with corn and soy probably wouldn’t be very organic, on account of those foods usually being heavily sprayed and genetically modified, but that’s the beauty of this system. The most important characteristic that is needed for the spray, is that it must be gritty. There’s no telling how many different substances could be used.

So far it’s been pretty successful. Forcella claims that it kills about 75% of the weeds, and the rest are often so stunted that they can’t compete with the crops. He also added that “We’ve been getting season-long weed control of about 80 to 90 percent, which isn’t perfect, but most organic farmers would be happy with that amount of weed control.” This could also prove to be an effective tool against the pesticide resistant superweeds that have been plaguing farmers lately.

The only drawback is the cost, which is about 5 times as much as spraying herbicide. However, the technology is still in its infancy, and that cost could easily go down in the near future. It sounds like an incredibly simple process (I’m kind of surprised nobody thought of it before) and the materials that are used can be cheap. I’d imagine that it won’t take much to improve the efficiency of the design and the techniques involved in its application. And with the higher yields this would undoubtedly create, it might finally put a dent in the notoriously high costs of organic food.