From the Nature Conservancy:
How an ambitious tamarisk removal project on the San Miguel River set the precedent for future restoration work.
TAMARISK: A THREAT TO THE RIVER
The free-flowing San Miguel River extends for 80 miles from high-alpine headwaters above Telluride, to a desert confluence with the Dolores River near the Utah border. The area is marked by Cottonwood forests with understory of willows and skunkbrush sumac and supports an array of wildlife such as great blue heron, American dipper, black swift, river otter, beaver, black bear, and mountain lion.
In 2005, a watershed-scale conservation plan developed by the Conservancy and partners identified the invasion of non-native species specifically tamarisk, Russian olive, and Chinese elm as the highest threat to the riparian vegetation along the San Miguel River.
Tamarisk replaces native vegetation, and accumulates high concentrations of salts in the soil, threatening plant and animal species and local economy dependent on the river and riparian systems. Removing tamarisk and other nonnative woody plants from riparian corridors improves water quantity and quality, and restores the health of native vegetation.
AN AMBITIOUS GOAL
In response to this, the Conservancy designed a restoration plan and set an ambitious goal of making the San Miguel the first tamarisk-free river system in the Western United States, something that had never been tried before. Working with community members, landowners, the Bureau of Land Management and local government officials, the Conservancy educated stakeholders on the benefits of the project for the river ecosystem and garnered support from almost everyone in the watershed.
Starting in 2007, the project took seven years to complete. While not reaching the goal of a fully tamarisk-free river system, the woody invasive species abundance is drastically reduced in all of the areas that were treated. Analysis done in 2014 has shown that the removal work was a success and minimal continued management is needed.
A MODEL FOR RIPARIAN RESTORATION
“This comprehensive project was a first of its kind in the western United States and has become a model for large scale riparian restoration,” said Terri Schulz, director of landscape science and management for The Nature Conservancy in Colorado.
Efforts have expanded to projects on the Dolores River and prompted the establishment and expansion of groups such as the Tamarisk Coalition. By thinking about this work in the context of the whole watershed, the Conservancy was able to reach out to a wide variety of partners to provide leadership and manpower to the project and to grow the capacity for this work moving beyond the San Miguel watershed.
As the Conservancy plans for future restoration efforts, the tamarisk removal project on the San Miguel River provides an outline for how to successfully work together with communities, landowners and the government to complete projects and reach largescale conservation goals.