Springtime brings back warmer temperatures, green plants, beautiful blooms – and unfortunately heavy, damaging rain events.
Springtime brings back warmer temperatures, green plants, beautiful blooms – and unfortunately heavy, damaging rain events. Sometimes an after effect of these heavy rains is streambank erosion. This occurs when heavy rains make their way to streams, dramatically increasing the speed and force of the water. These flow velocities can be too much for the streambank and sections of the soil can be eroded away. In some instances, erosion is significant enough to remove a portion of the property and establish a new streambank edge. Another detrimental effect of this erosion is that soil is washed into the stream and suspended in the water column, which is a type of pollution (See MS4 Update: Why Soil Matters More Than You Think).
There are actions that can be taken to protect stream banks. Mechanical methods can be installed, this would include placing materials such as large rip-rap stone, timber pilings, stream rock veins, rock gabion baskets or retaining walls made of treated timber or metal sheet piling to hold the bank in place. These methods would offer immediate relief, but they can be extremely expensive and if not professionally designed and installed, they could fail in short order.
Another action that should be considered would be planting live trees and shrubs. This method requires a little forward thinking and is not an immediate fix, but it is much more affordable and if established properly, could offer a very long-term solution. Trees and shrubs along stream corridors offer their live root systems to hold soil in place and are called Riparian Buffers. The root systems of vegetation resists the force of storm surges in the river and keep the streambanks and the soil in its place.
There are many types of trees and shrubs that would be suitable for this purpose, but I would like to highlight one tree in particular for landowners to consider – the American Sycamore tree. The American Sycamore is a native tree and can be recognized by its mottled brown, gray and white bark that can look like a camouflage pattern. It is typically found growing wild along stream and river corridors and has the largest circumference and leaves of any hardwood tree in North America. It is a large tree with a potential diameter of greater than 10 feet, and a height range between 80 and 140 feet! They are a long-lived tree as well. A living tree was cut down in southeastern Indiana in 1970, it’s diameter was more than 7 feet, and it was found to be 430 years old!
As far as stream benefits, here’s what the Sycamore can offer. Their massive root systems not only hold and secure stream banks, but they also filter out sediments and other surface pollutants from the stream. These root systems also create flow eddies in the stream which can reduce erosive flow and offer resting areas for fish from strong flow currents. Their large size can offer shade to the stream channel too. This cools the water which increases dissolved oxygen and inhibits nuisance algae. The tree itself offers multiple wildlife benefits, it can provide cavities for shelter along with roosting and nesting sites for birds. The Sycamore is the preferred tree by Bald Eagles and the canopy of a mature tree can support a 2,000-pound Bald Eagle nest!
So, the next time you have a chance to drive or hike next to a stream, take a look and see if you can spot this amazing tree. Notice how the roots are securing the streambank and take a peek into the canopy and see if you can spot an eagle’s nest. I hope this will give you a new appreciation for the Sycamore and consider it an option as a streambank stabilization technique.
