Agronomy and Horticulture Department
Date of this Version
2009
Abstract
South-central Nebraska is recognized as a focal point of the mid-continent migratory waterfowl flyway. Substantial wetland alterations led to a critical need for restoration. Managers have restored wetlands by scraping with heavy earthmoving equipment to remove excess organic material and near-monocultures of reed canarygrass (Phalaris arundinacea L.) but managers report high costs and topsoil perturbation. Moderate livestock grazing was tested to compare results with those achieved with mechanical techniques. Advantages of grazing could include low costs and less soil perturbation. During the 2006 and 2007 growing seasons, we compared cover of bare ground and open water and plant species composition in mechanically treated, grazed, and untreated wetlands dominated by reed canarygrass to determine restoration success. Significantly less reed canarygrass and a higher percent composition of desirable species were found in mechanically treated areas as compared to grazed or control treatments. However, waterfowl food plants and marsh species were similar between treatments. Significantly higher percent cover of open water was found at mechanically treated wetlands possibly improving shorebird and waterfowl habitats. Both restoration techniques increased bare ground. Our findings reject the proposition that moderate livestock grazing is an effective technique in restoring reed canarygrass dominated wetlands in Nebraska and suggest additional research be conducted on intense, short-duration grazing in early spring.
Comments
Accepted for publication (2009) in Rangeland Ecology & Management Copyright © 2009 Nancy Nicolai and James Stubbendieck