Scientists take aim at weeds with baking soda, corn grits and walnut shells

This researcher from Agriculture and Agri-Food Canada has spent the last four years blasting his way through fields of weeds, looking for a way to kill them without using chemicals. So we're doing something called abrasive weed control, which is using an abrasive grit material to shoot at high velocity onto our weeds to try and kill them. So we're essentially just sandblasting our weeds. The sand blaster is from a local hardware store, but instead of sand, they're using some different kinds of ammunition. In the first year of the project, we looked at corn grit, which is just mashed up corn cobs, and walnut grit, which is just walnut shells smashed up. And again, my colleague in Quebec, she'd been playing around with baking soda in the winter. The researchers are looking for a way to control weeds that have become resistant to traditional herbicides using physical force instead of chemicals. Trying to damage the leaves, kill the growing point to prevent the plant from growing. Uncontrolled weed competition with potatoes can result in almost 50% yield loss. There have been some setbacks. It turned out walnuts posed a risk in potato fields because of nut allergies. The baking soda clogged up the hoses on the sandblaster, making it hard to spray. And it was expensive. You're processing potato producer, growing french fries and potato chips. This is probably not going to work out, just the economics there. Other Agriculture Canada scientists were doing the same kind of research across the country. In BC, the goal was to reduce weeds in fields of highbush blueberries. But the weeds were perennials with big root masses that grew back. But this researcher isn't giving up. He wants to create a weed-blasting robot. In discussion with the local universities to develop some sort of autonomous robotic weeder, it can travel along the blueberry rows. The four-year project on PEI is wrapping up. Mackenzie Gopsill hopes it will spark some interest from growers or an equipment manufacturer to turn this idea into a new tool for blasting weeds. Nancy Russell, CBC News, Harrington.