The Illinois Natural History Survey (INHS) has initiated a multi-year statewide study evaluating moist soil plant production in managed wetland units at key waterfowl areas throughout the state. Two Ducks Unlimited projects, Spring Lake Bottoms and Reily Lake, topped the list of 2005 survey sites in terms of total moist soil plant seed production.

Spring Lake Bottoms in Tazewell County secured the number one spot with 1,610.3 pounds of moist soil seed per acre of wetland. Reily Lake in Randolph County came in at number two with 1,472.8 pounds per acre. These two sites were approximately 50 percent higher than the statewide average of 941.7 pounds of moist soil seed per acre of managed wetland. INHS has determined that the two DU projects account for 6,253.6 potential “duck use days” (DUD’s) per acre and 5,719.6 DUD’s per acre, respectively.

Moist soil plants grow naturally in managed wetland units and provide a high quality food source for a variety of waterfowl species. A “duck use day” unit is used to describe the amount of moist soil plant seed that is needed to feed a duck for one day. In theory, if a wetland unit has 6,000 DUD’s per acre, there is enough plant seed to feed 100 ducks per acre for a period of 60 days.