Canada's weed hunters are setting their sights on natural alternatives to herbicides.
Dr. Andrew McKenzie-Gopsill is a research scientist with Agriculture and Agri-Food Canada (AAFC) at the Charlottetown Research and Development Centre.
"We're evaluating abrasive weed management or projectile weed management, it goes by a couple of different terms. It's really exactly as it sounds like. We're shooting a material directly at our weeds to try and control them. We're using essentially just commercial sandblasters and passing different types of grit and evaluating control of several priority species in a couple of different high value crops across Canada."
The technique was first developed by University of Nebraska researchers for weeds affecting corn crops.
McKenzie-Gopsill says they're evaluating two main materials.
"The first one is a walnut shell, so just ground up walnut shells and we're looking at two different grit sizes of that. As well as corn grit, which is just corn cobs ground up and looking at two different sizes there."
Agriculture and Agri-Food Canada (AAFC) scientists across Canada have teamed up to form the northern chapter of "weed hunters" as part of the Alternative Pest Management Solutions project to reduce pesticide and herbicide use.
Dr. Robert Nurse is hunting weeds in dry bean fields in Harrow, Ontario while Dr. Andrew McKenzie-Gopsill is tackling potato weeds at the Charlottetown Research and Development Centre on Prince Edward Island. Dr. Marie-Josée Simard, Saint-Jean-sur-Richelieu Research and Development Centre in Quebec, and Dr. Jichul Bae, Agassiz Research and Development Centre in British Columbia, are targeting common vineyard and blueberry weeds, respectively.
They are targeting the five most common broadleaf weeds, or non-grass weeds, in each crop.
McKenzie-Gopsill was asked about damaging crops in the process.
"There's definitely a little bit of crop damage that can occur...We are going after the crop has emerged, but we are going at a very early stage and we are directing our sandblasters along the side of the rows. Not directly at the crop but just right where a lot of those weeds grow right next to that crop row. We do see a little bit of damage there."
By 2024, the team hopes to find the best projectile material, its size and application rate, with weed control of more than 80 per cent without causing significant crop injury and yield loss.
AAFC says the results of this research could provide a quick, cost-effective and simple solution for farmers trying to control weeds in their crops and reduce the environmental impact of herbicide use.
The air-propelled abrasives being tested by AAFC would not require registration by Canada's Pest Management Regulatory Agency. Without the registration requirement, new projectile materials could be made available to farmers after only two years of small plot testing.