As a lifelong native of Illinois, I knew I wouldn’t grow up with mountains to explore in my backyard, so instead I spent my time adventuring in the next greatest frontier: local streams. Rivers and streams have always been fascinating in how different the plants and animals are when compared to terrestrial environments like woodlands and prairies, and even other bodies of water like lakes and ponds. I spent many a summer as a kid knee-deep in a stream, flipping rocks to see what cool critters were clinging to the bottom. Now as an adult working in the field of natural areas restoration, I haven't lost that sense of wonder but have had it grow even greater with an appreciation for the importance and benefits of healthy streams. However, as they are so different from the surrounding habitat, they present unique challenges when performing critical restoration actions. So, how do you restore a stream, and why is it so important to restore them?
Healthy streams play a critical role in the environment, and perform a variety of what are termed ‘ecosystem services,’ which can be defined as tangible benefits to humans from the presence of healthy ecosystems. These services include regulating services, where a healthy ecosystem provides some regulation of water quality, air quality, decomposition, pollination, carbon storage, and other varied services that helps moderate the natural world (and therefore, benefit human life as well). Looking more specifically at streams, when they’re healthy they can control otherwise harmful flood waters, provide a stable source of fresh water for drinking and other uses, trap excess sediment, and otherwise act as a natural source of water filtering and processing.
The plants and animals that utilize healthy streams are also varied, and often unique to those environments. Regarding insects, there are whole ‘orders,’ or groups of insects, that are considered aquatic as they spend most of their lives in water. These include dragonflies, damselflies, mayflies, stoneflies, and many others. Within these groups, many species are unique to stream environments, particularly healthy streams. Clubtail dragonflies, such as the russet tipped clubtail, are often found in streams and rivers with sandy bottoms, and as adults can be found clinging to the riparian vegetation nearby. Stoneflies are a particularly sensitive group of insects whose larvae are dependent on high-quality stream water, and because of this their presence can be used as indicators of water quality. While adult stoneflies are usually non-descript, there are some species termed ‘winter stoneflies’ that stand out as they are one of the few insects that emerge out of the water and are active in the heart of winter. If you’ve ever been on a bridge or near the banks of a high-quality stream in February and see small dark insects on the bridge or snow, there’s a chance you’ve seen the elusive winter stoneflies. We should also remember the unique plants along the stream banks, or ‘riparian zone’. These plants, which in the Midwest can frequently include Leersia oryzoides (Rice Cut Grass), Acorus americanus (Sweet Flag), and Justicia americana (American Water-Willow), serve an important role in the stream ecosystem. They provide shade to the stream, cooling the waters, help filter land-based nutrients, and stabilize the bank which reduces erosion.
However, all the valuable ecosystem services, flora, and fauna of streams require that the stream be healthy and of high water and vegetation quality, which too often is not the case. In fact, streams are one of the natural features most impacted by human interaction from unnaturally high flood levels, chemical runoff, pollution, introduction of invasive species, and channelization, all of which can lead to continual site disturbance. There is a need for landowners and managers to protect, preserve, and restore their streams, just as they are working to restore the nearby terrestrial habitat. So, how do you restore a stream?
There are many facets of stream restoration such as geomorphology, in stream habitat features, civil engineering, and the list goes on, but we will narrow our focus here to vegetation. Just like terrestrial environments, stream restoration requires knowing what you already have at the site, determining what you need, putting it into action, and evaluating the results, all of which can be summarized as flywheel ecology. The first spoke of this flywheel is investigation, planning, and prevention, to determine the unique nature and needs of your restoration site. Once that information is gathered, we can select the plants and seeds that would benefit your site the most, which is the second spoke. It is this step in the flywheel that we most recommend the use of ‘river and stream warrior plants.’ These are plants that provide significant benefits to stream restoration as they are hardy, tough competitors that can be quick to establish and thrive in a variety of stream habitat types. From low slope and mid slope to straight stream sections, there are warrior plants best suited for that battleground. These sturdy warrior plants help with the third spoke of the flywheel, establishment and management, where the focus is to make sure the plants you selected are established in and around the stream, and to manage these plantings to ensure that they out-compete undesirable species. The final, but critical spoke of the flywheel is evaluation. Are the warrior plants established? Are invasive species moving in? Are local plants and animals responding positively to the restoration? After evaluation, you’ve gained momentum to move back to the first spoke of the wheel and keep it turning to ensure your restoration site is a success.
That is truly the greatest aspect of flywheel ecology, that it builds its own momentum year after year. As you keep moving along the flywheel, each step builds momentum for the next, making your goals easier to achieve and making it much more difficult for invasive species to stop the momentum and move in. If you’d like to hear more about flywheel ecology and warrior plants, you can find a great presentation given by Chief Ecological Officer Nick Fuller here. Want to know more? You can schedule a free phone consultation here, and start discussing the unique challenges and solutions of your restoration site. Stream restoration is truly the next frontier of land management, so let us help you get the wheel spinning today!