Overrun by thistle

Asked May 17, 2018, 1:43 PM EDT

About 5 yrs. ago my next door neighbor stopped mowing a portion of her backyard in order to form a "nature preserve" . Our yard is fenced and this un mowed area abuts our fence. As the weeds took over she acquired quite a crop of thistle. As I am on the downwind side of her I now am overrun with it. I have tried everything I know but it comes back in short order even thicker. What can I do ?

Carroll County Maryland

1 Response

Is it an option to talk to your neighbor and ask if she would be willing to mow the area once per year to control formation/spread of the Canada thistle seed? It is a very difficult weed to control and if there is a constant source of fresh seeds nearby, then it's going to take a lot of persistence to control it on your side of the fence.
This perennial’s root system holds huge energy reserves. Taproots send out side roots as deep as three feet and can regenerate from a one-inch-piece. If you have it coming into a lawn area, then regular mowing can help to starve the root system. Beyond that, the other option would be to spot-treat plants with a post-emergent systemic herbicide (Roundup or Rodeo), being careful not to apply it to any desired ornamental plants. https://www.invasive.org/weedcd/pdfs/wgw/canadathistle.pdf