An Effective Site-Restoration Planting Method: Incorporating Seed into Aggregate Clay Particles

摘要

Overview. Ecological restoration projects are increasingly popular in the United States and throughout the world as a result of wetland and habitat losses and the recent recognition of the multitude of benefits associated with these systems. Often, ecological restoration is incorporated into remediation, reclamation, and beneficial use projects. Restoration projects can sometimes involve capping or post-dredging restoration as part of a larger remediation strategy. During the course of the restoration project, establishing vegetation at a site through seeding can pose many challenges. SubmerSeed? is a new technology developed to incorporate aquatic or wetland seeds into a dense aggregate core wrapped with clay or clay-sized particles and polymers. These aggregates sink when applied through water, reducing the potential for the seed to be carried away by subsequent wind or flooding. This seeding method can be used in a variety of applications including wetland restoration, stream restoration, habitat reclamation areas, waste water facilities, and confined disposal facilities (CDFs). Laboratory testing of this technique has shown that the material has a high ability to keep seeds in place and provides reliable germination success. Field applications have demonstrated similar results. Background/Objectives. Planting with greenhouse seedling plugs is expensive and the seedlings are susceptible to stress associated with changes in temperature and soil characteristics. Direct seeding using traditional methods such as drilling, hydroseeding, and hand-broadcasting can generate unpredictable results, as often very small seeds are challenging to disperse uniformly and are prone to being carried away by wind and moving water. Additionally, vegetating a site that involves a capping material can be challenging, as the use of heavy equipment or walking on the cap in order to seed or transplant plugs can be impractical. As a result, there is a need for a planting method that is not labor intensive and that is cost-effective; easily incorporated into projects involving capping materials; and successful at keeping seeds on the site in a manner that facilitates germination. Incorporating seed into aggregate clay particles is an effective seeding method that has undergone laboratory testing at the USDA Natural Resources Conservation Service Plant Materials Center in Aberdeen, Idaho, to measure its effectiveness. Approach/Activities. The success of this seeding method was evaluated in laboratory and field studies. A review of these case studies will be presented. Results/Lessons Learned. This seeding option readily allows for the introduction of a single species or a suite of desired species without significant additional labor. Further, successful seeding can assist with remediation and capping projects by increasing root