DESCRIPTION
Snohomish County proposed to restore riparian habitat by continuing knotweed control in first and second priority restoration areas along the SF and NF of the Stillaguamish River. The goal of the project is to accelerate the natural recruitment and to re-introduce native conifers along the South Fork Stillaguamish and on the North Fork from the Oso slide and downstream by reducing knotweed infestations to a level where knotweed is no longer an environmental threat.
Snohomish County worked to restore riparian habitat along the SF and NF of the Stillaguamish River. As work under the grant progressed, they focused only on the NF of the Stillaguamish river and Squire Creek. A bulk of the work under the grant occurred downstream of the Oso slide, however there were also treatment and planting sites upstream of the Oso slide.
Under the grant Snohomish County was able to treat over 137 acres of riparian habitat along more than 45.5 miles of river for invasive knotweed. Post treatment, Snohomish County installed native riparian plantings covering almost 13 acres of riparian area. They exceeded their goal of restoring 0.5 miles along the river, planting native conifers and shrub species along 1 mile of river.
Efforts under this grant reduced the knotweed populations along the NF of the Stillaguamish river to help improve salmon habitat in the basin by allowing natural recruitment of native tree and shrub species. Additionally, the planting efforts will help jump start the seed source to spread throughout the basin. Though this project is considered successful, there is further work needed to continue in the both the NF and SF of the Stillaguamish river in order to eradicate knotweed from the basin.
