Monday, August 6, 2007 - 1:50 PM

OOS 3-2: Planning riparian restoration in the context of Tamarix control in western North America

Mark K. Briggs, Rincon Institute, Patrick B. Shafroth, US Geological Survey, Vanessa Beauchamp, US Geological Survey, Kenneth Lair, Bureau of Reclamation, Michael L. Scott, US Geologic Service, and Anna A. Sher, University of Denver & Denver Botanic Gardens.

Riparian areas throughout the world are declining due to numerous threats, including encroachment of exotic species. In the western US, millions of dollars are being spent to control invasions of Tamarix, an introduced tree from Eurasia that has colonized bottomland ecosystems along many rivers. A project to restore Tamarixdominated parts of the Big Bend reach of the Rio Grande is offered as a case study. The overall project has several objectives, including the improvement of wildlife habitat, enhancing sediment reintroduction, and promoting natural regeneration of native riparian plants. These objectives are similar to the aim of efforts along other rivers where improving ecological conditions is an implicit goal.

Yet, in many cases, there is little emphasis on a process or principles to effectively plan restoration activities. Indeed, recent research has shown that efforts that focus solely on Tamarix removal are unsuccessful at restoring native riparian vegetation. This paper addresses the need for more careful and rigorous restoration planning in the context of Tamarix control.

We discuss in greater detail the biotic and abiotic factors central to the evaluation of potential restoration sites. While many projects begin at the implementation phase, which includes the actual removal of Tamarix, we stress the importance of pre-project planning that includes: 1) clearly identifying project goals, 2) developing realistic project objectives based on a detailed evaluation of site conditions, 3) prioritizing and selecting Tamarix control sites with the best chance of ecological recovery, and 4) developing a detailed tactical plan before Tamarix is removed.