Wetlands
What is a Wetland?
According to the United States Environmental Protection Agency, Non-tidal marshes are North America’s most prevalent and widely distributed wetlands. They are primarily freshwater marshes, although some are brackish or alkaline. They frequently occur along streams in poorly drained depressions and shallow water along the boundaries of lakes, ponds, and rivers. Water levels in these wetlands generally vary from a few inches to two or three feet, and some marshes, like prairie potholes, may periodically dry out completely.
Highly organic, mineral-rich sand, silt, and clay soils underlie these wetlands. At the same time, lily pads, cattails, reeds, and bulrushes provide excellent habitats for waterfowl and other small mammals, such as Red-winged Blackbirds, Great Blue Herons, otters, and muskrats. https://www.epa.gov/wetlands/what-wetland
Where are some recognized wetlands in the Wawasee Area Watershed?
The Wawasee Watershed has four recognizable wetlands. Conklin Bay and Johnson Bay are two of our most recognized wetlands on Lake Wawasee. Syracuse Lake Wetlands is located on the east side of Syracuse Lake and Turkey Creek Wetland along the Turkey Creek Tributary east of Lake Wawasee at the outflow of Lake Wawasee.
What plants would I see in a Wetland?
Most of the wetland plants we see are called cattails and phragmites. But are these the best plants that make up a diverse wetland? They are two species of plants that will grow where the land is primarily wet but can dry out. Their roots are a tangled mass intertwining to help hold themselves upright. The cattails were once native (narrow-leafed cattails whose leaf measures about ½ inch in width). Still, other varieties have been introduced into the population and are considered hybridized.
The purpose of the native cattail is to slow down the water coming into the lake/river/etc., collect the sediment, and hold the ground to prevent erosion. The wetlands absorb the excess nutrients before they get to the open water to cause excess weed growth. They are known to be great nurseries for nature’s young animals, including fish, geese, invertebrates, frogs, and many more. And they sequester carbon. According to naturalshore.com, the hybridized cattail is “aggressively invasive; can tolerate a greater range of water depths and salinity, allowing it to invade many types of habitats.” “This aggressive behavior of forming large mats is quite effective in choking out native emergent and wetland plant species like bulrush and various sedges.” The native cattails reproduce typically from seeds, but the hybridized ones are fast growers. The phragmites are not native. They are very aggressive growers, have dense roots that small animals find hard to maneuver around, and outcompete the cattails (native or hybridized) for growing space. They also produce millions of seeds on their grass-like seed heads that stand about 6-9 feet above the surface. These are not desirable wetland plants but have invaded nonetheless because they found outstanding living conditions.
Are the Wetlands still filtering?
There should be various plant life in a diverse wetland population, not just a monoculture of cattail plants. But our question at WACF is whether the hybridized cattails are still filtering the water before it enters the lakes in our area.
We are researching that question and do not have a good answer yet. We know that once cattails and other wetland plants die, their nutrients return to the substrate (sediment). So when it rains, or there’s a greater flow through the wetland, these extra nutrients are not absorbed but may be given off to the lake. In this case, the wetland may act like a sink – holding the phosphorus and nitrogen but draining it when the waters are high or the flow is fast.
So what can be done?
There are various options to try to regenerate a biodiverse wetland. WACF is trying one of those options in a tiny area near the Conklin Bay Trail. We are partnering with the DNR, Department of Fish and Wildlife, and Syracuse-Wawasee Trails to see if a diverse wetland can be established, how long it will take, and how long it will last. The University of Michigan (phys.org) has successfully tried this in Michigan along the Lake Michigan shoreline since 2011. They harvest the cattail plants (they are finding many uses for harvested cattail plants) and allow the sun to shine on the bare ground, which helps the native seeds that have been dormant for years to germinate.