Springtime Increases the Risk of Shoreline Erosion
As spring sets in and the ice melts off our lakes, water levels typically rise and the potential for shoreline erosion increases. Soils become saturated higher along the shoreline banks, and this condition makes those areas more susceptible to wave action. Bigger lakes experience more wave energy from wind, and in addition, they often play host to wave generating ski and wakeboard boats. In general, native plant communities are able to better cope with high water levels, compared to turf grasses and ornamental plant species. Many of our restoration projects have to do with transforming degraded shorelines back to ones that support a diversity of Minnesota native plants.
High Water
Minnesota native wetland and shoreline species are well adapted to tolerate a wide variety of soil moisture conditions and even flooding. In contrast, turf grass will last maybe a week underwater before it starts to die. For a majority of our projects, we introduce a suite of native species that flower at different times during the growing season. These natives look great and provide essential shoreline habitat. A few examples of these shoreline plants are blue lobelia (Lobelia siphilitica), cardinal flower (Lobelia cardinalis), sneezeweed (Helenium autumnale), and blue flag iris (Iris versicolor). These native wildflowers also provide critical food and habitat for our pollinator species.
Wave Energy
Wind and boat traffic can produce some pretty substantial waves in our metro area lakes. This wave energy can wash out and remove soil along the shore, especially during high water. In conducting site assessments for our clients, part of our job is to figure out how to best stabilize eroded shorelines. In most situations that we run into, we can use native plant communities to stabilize shores. To protect shores early on in the restoration process, we may use biodegradable erosion fabric, and biologs (biodegradable logs filled with coconut fiber and wrapped in a coir twine material). Native plants are introduced into these materials. As the native plant community becomes established, these erosion control products will slowly decompose over time. In some situations, planting a strip of native emergent vegetation (plants that grow in the water) in front of shorelines makes good sense. This vegetation will break up and absorb wave energy, and also provides excellent fish and wildlife habitat. Research the possibility of using arrowhead (Sagittaria latifolia), bur-reed (Sparganium eurycarpum), hardstem bulrush (Scirpus acutus), and softstem bulrush (Scirupus validus) on your shoreline to create a lush, dense stand of these native plants.
Traditional Turf Grass
Our European heritage taught us that turf around our property looks good and conveys proper care of the landscape. Unfortunately, turf along lakeshores can create some pretty big problems. Turf grasses have extremely shallow roots and create a very thin thatch layer, which makes them quite poor at stabilizing soil at the water's edge. In addition, turf along the shore can be considered a biological wasteland with extremely low diversity. With our clients, we often talk about striking a balance among turf, recreational areas, and natural shoreline buffers. A good design will allow for turf and high quality, beautiful, stable, natural shorelines. Native plants have robust and deep root systems that naturally armor shorelines. Maybe you have the opportunity to reduce your turf areas and use native plants to combat wave energy and create some exceptional habitat?
Spring is in the Air
Spring is officially here! If you have any questions about erosion problems or other early season issues facing your shoreline, feel free to contact us today! Give us a call or visit us online at www.naturalshore.com. We also want to stress that shoreline restoration can be very technical and complicated. Before taking on a do-it-yourself project, we would like to encourage you to have a trained restoration professional review your plans.