Wednesday, September 4, 2013

Pristine Waters Become Infested with Eurasian Watermilfoil


Located about six miles northwest of East Troy, Wisconsin; sits a small 95 acre lake surrounded by high quality wetlands and rich marshes.  In terms of ecological importance, Lulu Lake ranks high on the list of Wisconsin’s lakes.  The lake and its watershed comprise one of Wisconsin’s highest quality natural areas.
Prior to electric refrigeration, Lulu Lake was known for its “winter agriculture”.   The ice from Lulu Lake was especially prized by breweries and dairies for its pristine cleanliness.  Area farmers and farmhands would take teams of horses and hand-powered tools to the lake and cut blocks of ice and move them into nearby icehouses. 

This photo of the massive Lulu Lake ice house, which measured 250 x 450 feet and was owned by the Kinckerbocker Co.  Lulu Lake ice was highly prized by breweries and dairies for its pristine clarity.  Rail car loads were taken from theice house to Milwaukee and Chicago via the Chicago Milwaukee and St. Paul Railroad, which had a spur to the ice house along its Elkhorn to Eagle Line.

Ice cakes weighing nearly 200 pounds were stored in these icehouses until shipment; usually by rail in special boxcars.  Sawdust, marsh hay or snow would be packed between the blocks to keep them from freezing together.  The ice would be shipped around the region, to Milwaukee and Chicago nearly all year long.The hard, clear water is home to nearly 60 species of fish, including five that are threatened or endangered, and 14-15 species of mussels, including one where Lulu Lake is the only place in the state it still reproduces as well as a diverse population of amphibians, reptiles and fauna. 
The shoreline surrounding Lulu Lake is 97 percent owned by the Department of Natural Resources and the Nature Conservancy.  It has no boat entry point other than by canoe via the Mukwonago River or by boat through the channel from Eagle Spring Lake.  There are no beaches as the shoreline is all natural, surrounded by a large wetland, streams, bogs, prairies and woodlands.
Unfortunately where there are boats, there are aquatic invasive species and ten years ago Eurasian water milfoil was found in the glacial formed lake.  On a typical summer weekend there can be up to 10o pontoon boats in addition to canoes and kayaks.  That is a lot of material getting through from various places on the boats and a lot of vegetation getting chopped in propellers to settle and establish in a new location on the lake. 


Once it takes root, milfoil forms thick mats of tangled stems that make recreational activities, such as swimming and fishing difficult and sometimes impossible.  It impairs the ability of fish to spawn and displaces native aquatic plants that cranes, ducks, geese, and other waterfowl need to survive. 
To help rid the lake of Eurasian watermilfoil, several times a year The Nature Conservancy mobilizes teams of scuba divers, snorkelers and interns in canoes to remove the thick clusters of the invasive species.  The milfoil is hand pulled and loaded into buckets on the canoes.  The buckets are taken to shore where they are left to dry and then later burned.
Dr. Timothy Gerber, professor of biology at UW-LaCrosse working with Jerry Ziegler, southeast Wisconsin land steward with the Nature Conservancy developed an innovative technology they hope will prevent the milfoil from returning and reestablish native aquatic plants in the process.
Native plants are interwoven into large mats, which are then submerged directly over areas where milfoil was removed.  This is new technology, so its effectiveness will take time to evaluate, but everyone involved is hoping that the tedious process of pulling and matting will benefit not only Lulu Lake, returning it to its former glory, but will benefit the entire 18-mile Mukwonago River System.


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