Russian thistle, also known as the ubiquitous tumbleweed. A new herbicide called Matrix (rimsulfuron) will be available this spring for use in apple, cherry, and pear orchards. Tim Smith, Washington State University Extension educator who has been testing the product for four years, said it is a broad-spectrum herbicide that seems to be safe for trees and effective against many weeds, but it doesn’t control all weeds. “If you use it in your orchard by itself, you’ll find out how much Russian thistle you have, because it doesn’t work at all against Russian thistle,” he told growers at the Lake […]