Forterra Riparian Restoration

Help us restore healthy riparian buffers for the Puget Sound region’s rivers.

If you are a landowner along the Cedar River, Bear Creek, or Thornton Creek and are interested in signing up for our program, please fill out a permission form below. You can fill it out digitally and email or print it and send it to us in the post.

Click here for a digitally fillable Knotweed Permission Form


  • Download the form.
  • Electronically sign it.
  • Save it to your computer or device.
  • Email to us at
Click here for a printable Knotweed Permission Form


  • Print the form
  • Fill out and sign
  • Mail to us at: Forterra, PO Box 4189, Seattle, WA 98194

If you need help with this form or process, please contact us at: (206) 549-3836.

Thank you for your support in our knotweed eradication program!