Upper Souris National Wildlife Refuge

Grazing

Upper Souris National Wildlife Refuge uses cattle as a tool to manage grasslands for the benefit of wildlife habitat. While the Refuge staff uses grazing to gain desirable wildlife habitat conditions, grazing cooperators gain quality forage for their cattle. In general, the Refuge subscribes to short duration, high intensity grazing to benefit grasslands. Grazing benefits grasslands in the following ways: 

• Stimulates new plant growth
• Increases native plant diversity and reduces invasive weeds 
• Loosens the soil and prepares a seedbed for native plants
• Reduces thatch and recycles nutrients into the soil 

Haying and Mowing

Haying and mowing at the right time of year benefits grasslands in the following ways:  

• Increases plant diversity and yield
• Limits the spread of noxious weeds
• Reduces the use of herbicides
• Increases plant density for the benefit of wildlife

Prescribed Burning

Prescribed burning is used to manage grasslands the way natural fires once did. Historically, natural fires caused by lightning burned the grasslands and marshes, recycling nutrients, cleaning out old growth and promoting new vegetation. Refuge staff use prescribed burns to manage grasslands the way natural fires once did. Benefits of burning include:

• Improves native habitats and controls noxious weeds
• Reduces thatch and promotes seed germination
• Increases nesting and escape cover for birds
• Stimulates the growth of sprouts which are food for deer and other wildlife     

Invasive Species

Invasive weeds have few natural enemies, so insects that feed on these plants must be introduced onto the Refuge from the weed's native land. Biological controls such as beetles, reduce the amount of pesticides used on the Refuge and attack only the target weed species.

Water Management

Lake Darling, a 9,600 acre lake named in honor of Ding Darling, a political cartoonist and first director of the U.S. Bureau of Biological Survey (predecessor to the U.S. Fish and Wildlife Service) is the largest of several water impoundments on Upper Souris National Wildlife Refuge. The lake's primary purpose is to furnish a regulated water supply to smaller marshes downstream and especially to the larger marshes on the J. Clark Salyer National Wildlife Refuge, 110 miles downstream. The lake is designed to hold a two-year supply of water to safeguard marshes downstream against the threat of drought. The dam also makes it possible to reduce the flooding and to regulate releases during periods of low flow. Both operations benefit people in the valley below the dam. 

In 1998, the dam also became an integral part of the Souris River Flood Control Project that assists in providing 100-year flood protection for the city of Minot.