Wetland studies being conducted by the LKWA

The LKWA was awarded $30,000 in state funding through the Wisconsin Department of Natural Resources to conduct three separate wetland studies around Lake Koshkonong. The studies were developed by Natural Resources Consulting, Inc. (NRC) in conjunction with LKWA members and are designed to:

• Evaluate the florist quality and values of the wetland communities adjacent to Lake Koshkonong.
• Describe potential impacts to these communities due to water level changes within Lake Koshkonong.
• Develop management recommendations that will ensure the long term sustainability of these communities.
• Raise public awareness on the importance of protecting these valuable resources.

Read more about each study below.

Wetland Plant Community Assessment - Complete

The LKWA was awarded a $10,000 Lake Planning Grant to conduct a comprehensive vegetation survey and community quality assessment within wetlands adjacent to Lake Koshkonong. There are approximately 4000 acres of wetlands comprised of various community types adjacent to Lake Koshkonong. Based on information collected during preliminary wetland investigations many of these wetland communities contain a substantial diversity of both flora and fauna and contain significant functional values.

The objectives of this study were to:

• Develop a detailed plant species list of the wetland areas.
• Assess the overall wetland quality.
• Quantify the plant communities.
• Determine potential impacts of increased lake water levels on the wetlands.
• Make management recommendations that will protect, enhance, and provide long-term sustainability of these wetland communities.

Floodplain Forest Study - Complete

The LKWA was awarded a $10,000 River Protection Grant to conduct a detailed assessment of the floodplain forest communities adjacent to Lake Koshkonong. There are approximately 1000 acres of floodplain forest adjacent to Lake Koshkonong comprising 25% of the total wetland area. These floodplain forests are some of the highest quality of their type in southern Wisconsin.

These communities are important migration corridors for wildlife habitat, neotropical interior bird species, fish spawning habitat during spring flooding, amphibian and reptile habitat, and have a substantial timber value. Many of the floodplain forest areas have been identified by the WDNR and several wetland and forestry experts as being highly susceptible to significant adverse impacts due to increased lake water levels primarily during the latter part of the summer growing season.

The primary objectives of this study are to:

• Evaluate and describe correlations between historic and present lake water levels with the long-term growth rates of the floodplain forest trees.
• Address potential impacts of the proposed water level increase on these communities.

Current status (Updated August 2005)

This study has been completed and the final report (pdf) was issued in February 2005. For your convenience, the summary is repeated here:

We predict the following changes in the floodplain forest communities of Lake Koshkonong if average late-season water levels are permanently increased by 0.6 ft:

1. Mortality of silver maple and green ash growing at lower elevations in the floodplains. Many trees at low elevations and at the lake edge can be expected to be uprooted as their root systems are flooded.
2. Low relative elevations in the forests may be colonized by other less valuable tree species (e.g. willow species and cottonwoods), or they may no longer be suitable for growth of trees and convert to wet meadow/shallow marsh communities.
3. A general reduction in the growth rate of all three of the dominant Lake Koshkonong floodplain forest trees. We expect this decline to be especially pronounced in green ash, given the evidence that its growth rate has already declined with higher late-season water levels in the lake.
4. A shift in community composition so that the relative dominance of silver maple increases in the floodplain forests at higher elevations, and swamp white oak is nearly, or completely, eliminated over time.

Eastern Prairie Fringed Orchid Study - In Progress

The LKWA was awarded a $10,000 Lake Planning Grant to conduct a thorough investigation of several Eastern Prairie Fringed Orchid populations to ensure protection of these rare plants by improving their habitat and gaining a better understanding of the important hydrologic factors that influence their continued survival.

The Eastern Prairie Fringed Orchid is rare wetland plant that has declined more than 70 percent from original county records in the United States. Now only 59 populations exist in 6 Midwestern states, including Wisconsin.

Several small populations of this unique species were discovered in wetlands adjacent to Lake Koshkonong in recent years. Due to this orchid's rarity, very little information is known about this species such as best management practices and hydrologic influences.

The primary objectives of this study include:

• Development of a short and long term management strategy.
• Enhancement of the populations by understanding the hydrologic influences.
• Protection of the populations by identifying the correlations between water levels in Lake Koshkonong and water levels at the orchid sites to determine if adverse impacts will result from increased lake water levels.

Current status (Updated September 2005)

After surveys of exact elevations were performed, electronic well monitors were installed at 6 sites in wetlands that contain orchid populations. These monitors will measure and record ground water levels at least hourly and store the data on a computer. Correlations between the hydrologic conditions and the success of the orchid populations will be tested.

Lake Koshkonong Wetland Association

11305 Vogel Road

Milton, WI 53563