Organic Wetland Restoration

Starting in the summer of 2018, Mosaic has been a contributing partner with multiple agency and private organizations to restore land previously used for agriculture to a forested wetland along McKay Creek in Hillsboro, OR. The project has prioritized the use of organic restoration techniques such as cultivating, cover cropping, hand removal of invasive plants, and mowing. Certain areas of the project were well suited to cultivation and cover cropping, while other areas, especially along the creek’s banks needed hand crews for mechanical and manual removal of invasive species.    

Nearly half an acre of the site was mowed, cleared of blackberry roots, and covered with twelve inches of wood chips to suppress regrowth. To ensure that the wood chip amendment would not be washed away by highwater, coir fabric was staked on top to hold it in place. 27,000 live stakes of willow, dogwood, ninebark, swamp rose, snowberry, and thimbleberry were installed into these areas. This method has been very effective in quickly transitioning areas dominated by reed canary grass and Himalayan blackberry into a native scrub-shrub plant community. The thick layer of wood chips helped to suppress the weedy regrowth and offered a fertile growing medium for the live stakes. In most locations, we saw vigorous growth in the first season after installation.    

We look forward to improving the organic techniques applied, while sharing the successes and lessons-learned with other land managers.