Thursday, June 19, 2014

Plant Survey Completed! It's all good news.

Weyauwega Lake is now in it's second year of being at level. Last year we dealt with the non-aquadic plants in the process of drowning in the deeper water. We also noticed flowering rush, an invasive species that greatly concerned us. To that end we began to develop a replanting plan to introduce desirable aquatics in sufficient number to outpace the invasive species. We needed further research and a plant survey before moving forward. We now have that survey. "

Lake Survey:

Lake Weyauwega Site Visit

On June 17th Ted Johnson and Eric Evensen with the Wisconsin DNR visited Lake Weyauwega to investigate reports of large Eurasian water milfoil beds.  Upon inspection no Eurasian water milfoil was found in the lake.  Algae covered coontail and common waterweed may have been mistaken for EWM.  However, two other invasive species were seen in large numbers; Curly leaf pondweed and Flowering rush.  Curly leaf pondweed was found throughout the lake and in most cases was topped out at the surface.  No turions were observed on the CLP.
Flowering rush colonized the exposed lake bed from mid-lake to the upper end during the recent drawdown and can still be found in large numbers on the upper end of the lake.  The main channel on the upper end of the lake is free of vegetation and easily navigable.  The channel was lined with uprooted, dying flowering rush.  The rest of the upper end is colonized by the flowering rush.  Most of the flowering rush is growing in 3.5 – 5.0 feet of water which is outside of its preferred habitat.  The Flowering rush was easily pulled from the lake bed and had a very shallow, small root system.  It is hard to determine how long the flowering rush will persist but the plants exhibit very evident signs of stress.

A full species list of plants observed:
1.     Flowering rush (Butomus umbellatus)
2.     Common waterweed (Elodea canadensis)
3.     Coontail (Ceratophyllum demersum)
4.     Curly leaf pondweed (Potamogeton crispus)
5.     Flat-stem pondweed (Potamogeton zosteriformis)
6.     Long-leaf pondweed (Potamogeton nodosus)
7.     Water stargrass (Heteranthera dubia)
8.     Small duckweed (Lemna minor)

9.     Large duckweed (Spirodela polyrhiza)

This is all very good news for the lake. Before Weyauwega Lake was drained there were only three species found in the lake. We now have nine. We anticipate this will improve. We are moving forward with our plans to keep the lake healthy. 

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