I had two mounds of dirt on my property leftover from when we moved here that I haven’t gotten around to landscaping. Like much of the perimeter of my yard, where these mounds of dirt lied, they were infested with knotweed. I have been weed whacking and mowing these mounds off and on for two years. I decided it was finally time to bulldoze them and destroy any roots or rhizomes (i.e., tubers) that I could find underneath. It has been surprisingly hot out for this time of year and there has been no sign of rain for the past week or so and for the next week or so. I figured this would be a good time to disturb the soil, remove the rocks, and hope that any roots remaining which I missed to burn would dry out from the lack of rain, heat and exposure. Plus, afterwards these areas would be easier to mow and manage any future knotweed sprouts.
To get started, I got a fire going from the free wood I’ve received from Chip Drop next to the more infected site. Next, I used my John Deere 1023e with a frontend loader to tear the ground apart from the mound of dirt roughly measuring 20′ x 8′ x 2′. As I tore through the mound I unearthed countless large rhizomes and roots measuring anywhere from 3-6 feet long. I periodically picked up each one I could find and threw them on the fire as I tore apart the mound of dirt and flattened out over a hillside. I know the smallest fragment of root can spawn a new plant, but I’m confident that the tide has greatly shifted in my favor from this effort. Only time will tell, but it should be easier to mow and manage the knotweed from now on.
The other site is more out in the open and I’m confident it will be eliminated from Japanese Knotweed with persistent mowing and time. I used the John Deere 1023e with the frontend loader and a landscape rake attachment to make short work of this site. I found no large roots or rhizomes here, so nothing needed to be burned from this location. Again, this patch of knotweed is fairly isolated and will be gone in time.
With this and past efforts, I estimate I will have eliminated or have all but won the war on knotweed for about 50% of my yard where it was infected. I will continue to monitor all known infected sites in the future as I know it can continue to survive years after it seems to be all but gone. The remaining segment is about 200′ long along the northern side of my property on an embankment. I have constantly weed whacked this section and it is mostly on the edge of woodlands, where the shade and limited sunlight from a northerly facing direction has helped greatly to reduce this stand of knotweed. Due to the steep embankment I can’t use my compact tractor to manage it. However, I have used small isolated and quick burning cardboard fires with some success. Plus, I do plan on using the smothering technique with additional free or cheap mulch I have recently received from Chip Drop to further reduce this area of Japanese Knotweed. Thick blankets of mulch really put a damper on things for the Knotweed!