Remediation Plans in Action for Knotweed in Town Center

early knotweed patch
Photo credit: Town of Weston communication

This afternoon, Weston Town Manager Leon Gaumond sent out a communication about the plan for removal and remediation of the Japanese Knotweed recently discovered in Town Center. You can read about the discovery of that knotweed in the Owl here and here.

Here is the communication in its entirety (if you did not receive it in your email, you can sign up for Town information here. This is the real deal–the Owl occasionally makes things up. No, not purposefully).

The Town Center Improvement Project Team is aware of the knotweed that has sprouted in the newly established Knox Park and other areas within the project limits. This has also been noticed by many concerned residents due to its highly invasive nature. The purpose of this communication is to outline the remediation plan to allay those concerns.
As soon as the weed was noticed, the project managers engaged landscape, horticultural, and environmental experts and advisors to review the problem onsite and to help develop a strategy to remove the invasive plant from spreading and creating further damage.  

Remediation Plan
The plan that will be followed involves treating the soil that has knotweed sprouts with multiple applications of glyphosate, a broad-spectrum systemic herbicide. Soil replacement was considered; however, the remediation team advised against that course of action due to the inability to guarantee the seed and plant would be effectively removed, which could create the same issue we are currently facing. 

Pauses in between applications will be taken and the planting sites will be monitored for new sprouts before the next application is conducted. Work around existing trees and plants will be taken with great care by removing the knotweed by hand around the tree and exposed roots and the spray will be controlled with a wand and/or shield.  New trees and plantings will be put on hold, including the White Fir (holiday tree), until remediation is complete. When the time is appropriate, hydroseeding grass will be applied. All areas within the project limit will be closely monitored and the above course of action will be taken as needed.
Application and Product
The glyphosate product that will be used to treat the area(s) are registered through the Environmental Protection Agency and the Commonwealth of Massachusetts Pesticide Program. The applicators are licensed by the state and appropriate signage will be posted in accordance with the state’s pesticide regulations. The application will be logged in the Town’s internal reporting system, which is provided annually to the state. 
Soil Source
The soil that was brought in to the planting sites came from the Town’s own soil supply at the Merriam Street Composting Facility. It is believed, but not yet determined, that the affected soil was capped but broken into during the digging and loading process with the heavy machinery. This soil supply has been identified and will be dealt with appropriately.

Out of an abundance of caution,  if any resident brought soil from the composting facility to their home they should be watching for knotweed sprouts in their applied areas and be prepared to take action to remove the invasive weed from their landscape. (Emphasis: the Owl’s)

The Owl feels zero surprise that the soil was from the Brush Dump. The Japanese knotweed issue there is quite well-known to anyone who walks or visits the Conservation land at College Pond. It is the Owl’s fondest hope that the Town considers remediation efforts at that site as well. In the meantime, as Mr. Gaumond’s note says: watch your gardens.

Many thanks to the town employees and volunteers who jumped on the issue as soon as it was discovered. We shall overcome.


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