Replanting for Restoration

Replanting for Restoration

Stewardship-in-Action (SiA) Program

This program is a community stewardship effort to restore the riparian zone on the Cedar River and its tributaries. Sponsored by SPU and led by Forterra, the SiA installs native plants and trees on public and private property. Forterra works with property owners to restore native plant ecosystems along the river shoreline that will benefit salmon and other river-dependent creatures for centuries to come.

For more information, contact Judy Blanco at Forterra: (206) 905-6890 or


EarthCorps crew member treating knotweed on banks of the lower Cedar River.

One of the most significant threats to healthy fish habitat along the lower Cedar River is knotweed. The spread of this invasive plant has emerged in recent years as one of the more alarming impacts of human development.

Knotweed surveys conducted by King County on the Cedar River in 2010 from River Mile 18 down to River Mile 11 showed nearly contiguous knotweed stands and indicate that approximately 92 percent of the mainstem within the project area is infested. Among the numerous invasives in the Cedar, knotweed is considered to be the most threatening due to its rapid growth, ability to quickly displace native vegetation, and alter soil and water chemistry.

To address this threat the City of Seattle has established a partnership with Forterra, the Friends of the Cedar River Watershed, and the King County Noxious Weed Control Board to restore riparian habitat along the lower Cedar River and tributaries that have been degraded by invasive plants, particularly knotweed. This partnership, known as Stewardship-in-Action (SiA), seeks to engage private landowners and residents of the lower Cedar River communities in hands-on restoration on their own properties. For more information on SiA, view this poster (pdf). With funding from a four-year grant from the Environmental Protection Agency, SiA is undertaking an ambitious program to eradicate knotweed by:


Community volunteers plant native species at a restoration site on the lower Cedar River.

  • Treating knotweed on private property
  • Providing assistance to landowners to restore their properties with non-invasive, wildlife-friendly plants
  • Conducting workshops to teach landowners best management practices that contribute to healthy watersheds, and to make resources available to landowners

View 2014 progress report (pdf)

Stewardship-in-Action has secured grant funding to plant natives plants on private property on the banks of the Cedar River.  If you own property on the Cedar River in unincorporated King County and are interested in receiving a FREE native garden on your Cedar River shoreline, please contact Judy Blanco at Forterra at (206) 905-6890.

View a map of knotweed treatment on the Lower Cedar River.