Biological control of Russian knapweed: Subanguina picridis Canada Purdue Invasive Oregon Invasive MTwow Forestry Images tnc weeds Montana Nez Perce By Trent Pietch. Updated By Emily 4/19/04. Updated By Jake Hockenberry 3/1/05. Updated by Matt Wideman and Ian Smith on the first of March, 2007. Back to Bio-Control-main mtwow.org HOME