By Maria Young, Forestry Intern
The water quality of the beautiful St. Croix and Namekagon Rivers has a surprisingly strong connection to how we manage our woodland property.
This connection starts with a cloud. During rainfall, a forest helps prevent sediment from running into the rivers and decreasing water quality. The forest floor slows rainfall runoff and filters nutrients while allowing the water to infiltrate the soil and water table. Tree roots create a strong soil structure, which decreases the probability of soil becoming dislodged and eroding. Additionally, the canopy in a forest prevents rain from directly impacting the ground—another factor that can cause erosion.
Erosion can be devastating to property and wildlife habitats along the river. Your woodland management can help decrease runoff, water pollution, and streambank erosion, all while benefiting your enjoyment of the river and all it has to offer.
Chemical applications such as pesticides, herbicides, and fertilizers can also impact water quality. Excessive use of harmful chemicals in land management is detrimental because they can make their way into waterways and harm the environment. Chemicals like phosphorus can limit the amount of plants and animals that can survive in an ecosystem.
When high amounts of fertilizer enter our rivers, plants and algae take up these nutrients and grow in larger quantities. When the plants die, detritivores such as phytoplankton come in to break down the algae, which in turn decreases the oxygen content in the water for other animals like fish and mussels. This process, known as eutrophication, is what created the dead zone in the Gulf of Mexico. By avoiding the overuse of harmful chemicals in our forests and yards, we can prevent eutrophication in our waterways. Planting native grasses and shrubs along the river can also help capture these nutrients before they enter the water.
Finally, trees along the riparian zone of a river help regulate water temperature. More trees means more shade, which means less of the river is exposed to direct sunlight. More direct sunlight increases the temperature of the water. Cold water holds more dissolved oxygen than warm water, which benefits the animals living in the water. Additionally, tree branches that fall into the river provide habitat for fish and invertebrates, such as crayfish. So by preserving and maintaining your forest, you protect water quality and all the creatures that call the river home.
To learn more about water quality and forested lands, check out these resources: