Canada thistle is found in every county in Montana. It can reach heights of up to four feet and has extensive root systems, which make it very difficult to control. The flowers resemble those of spotted knapweed. Both female and male flowers must be present for the plant to go to seed. One plant can produce over 3,000 seeds annually, but it spreads primarily from the roots.
Leafy Spurge
May 2, 2012 By allterrainweed
Leafy spurge is a common noxious weed that is very difficult to control because of its deep root structure. Hand-pulling this weed releases a toxic, milky substance, which can cause skin irritation. It can even cause blindness. Each plant can produce 30 to 130 seeds, and most of those seeds will germinate within 2 years. The plants can reproduce by root, as well.
Filed Under: Montana Weed Spraying