Socheata Lor, Carrie Reinhardt-Adams, and Jessica Larson are monitoring vegetation on study plots at the Upper Mississippi River National Wildlife and Fish Refuge, La Crosse District (2010). - Photo Credit: Kathy Carlyle

Restored wet meadow with native swamp milkweed in the foreground (2010) at the Upper Mississippi River National Wildlife and Fish Refuge, McGregor District (2010). - Photo Credit: Kathy Carlyle

Eric Nelson, Carrie Reinhardt-Adams, and Jessica Larson monitoring staff gauges during the pilot phase of the project (2010). Location: the Upper Mississippi River National Wildlife and Fish Refuge, La Crosse District. - Photo Credit: Kathy Carlyle

Reed canary grass has partially and in some cases, heavily, invaded nearly 40,000 acres of refuge lands in the Midwest and Mountain-Prairie Regions of the U.S. Fish and Wildlife Service. Encroachment of reed canary grass into floodplain forests and wet meadows has been observed throughout the United States. This is a huge management problem for national wildlife refuges and other land managers. To address this problem beginning back in 2006, National Wildlife Refuge System biologists developed an adaptive management project in cooperation with biologists from the U.S. Geological Survey, the University of Florida and others. The goal of the project is to ensure that efforts to control reed canary grass are well-informed and improve over time through the use of predictive models and a robust monitoring design. It will allow managers to make good, defensible decisions about when, where and how to treat reed canary grass to maintain or restore target communities and the wildlife they support. The pilot phase of the project is completed and is managed by the National Wildlife Refuge System. We provide an update on the project here.

Across the Midwest and Mountain-Prairie Regions of the U.S. Fish and Wildlife Service, 10 refuges were involved in the pilot project, including:

• Upper Mississippi River National Wildlife and Fish Refuge - Winona, La Crosse and McGregor Districts
• Minnesota Valley National Wildlife Refuge
• Port Louisa National Wildlife Refuge
• Squaw Creek National Wildlife Refuge
• Swan Lake National Wildlife Refuge
• Tewaukan National Wildlife Refuge
• Madison River Wetland Management District
• Rainwater Basin Wetland Management District

Investigators and Science Team members were drawn from U.S. Geological Survey Cooperative Fish and Wildlife Research Units of Florida and Georgia, the Universities of Florida and Minnesota and the Chicago Botanic Garden.

Although mechanisms for its increased dominance are varied, the reed canary grass invasion is linked to increased soil nitrogen enrichment, impaired hydrology and construction impacts to wetlands. In the Upper Mississippi River system, extreme flooding events deposit large quantities of nutrient-rich sediments on floodplains and kill nearly all of the sapling and seedling trees in many areas. Floods in the Midwestern United States appear to have accelerated the spread of reed canary grass in many large river floodplains throughout the Mississippi River drainage. Managers wanted to know, “What is the most cost-effective way to convert reed canary grass dominated lands back to desirable wet meadow and flood plain forest native vegetation?”

The project objectives were:

1. Control reed canary grass while promoting desired vegetation
2. Use logistically and economically realistic management actions with demonstrated efficacy that can be implemented on large scales
3. Address the key uncertainties representing common refuge management scenarios.

We targeted wet meadow and floodplain forest ecosystems. Management units were selected that represented plant compositions ranging from reed canary grass dominated to native species dominated. In reed canary grass dominated meadow sites, effectiveness of vegetation eradication followed by seeding native species was compared to managing the existing vegetation to promote native species. Grass specific herbicide (fusilade) and broad spectrum herbicide (glyphosate) were used to selectively treat reed canary grass or to eliminate all vegetation respectively. 

In forest sites, after eradication of all vegetation with broad spectrum herbicide, two revegetation approaches were compared:

• Reliance on tree seedling establishment via natural seed rain from surrounding forest trees
• Direct seeding with appropriate native tree species.

Long term monitoring protocols were developed to retain a high level of accuracy from data collected with reasonable field effort. In spring, only reed canary grass stem density is monitored. Monitoring at peak vegetation (August) requires recording cover categories of plant guilds and reed canary grass stem density. At forested sites we also record tree numbers and track whether plots have greater or less than 50% native herbaceous cover. Treatment protocols are based on routine management practices and include herbicide application, as well as broadcast seeding for forest and meadow sites.

The current state of management units is determined by vegetation cover and nitrogen level, and in forests, distance from forested edge. The probability of transitioning to an improved state (more native species or more trees) is determined through competing models for all possible management actions. This information is used to generate annual management recommendations for each management unit.

The Reed Canary Grass Adaptive Management Project is housed on a Department of Interior-accessible U.S. Fish and Wildlife SharePoint site. All relevant protocol and guidance documents are housed on SharePoint, as well as project final reports, records and publications. Field data collected in 2013 will be entered via a web-based portal directly into an access database housed on SharePoint and linked to the decision tool.

Action recommendations for each management unit will be disseminated to participants through the Reed Canary Grass AM SharePoint site.

For more information contact:

Kathleen Carlyle, RCG AM Project Coordinator, Kathleen_Carlyle@fws.gov, (608) 781-6301 or
Patricia Heglund, patricia_heglund@fws.gov, 608.781.6338.