written by: Sheryl Myers, Founding Board Member and Guest Contributor
Topsoil is the upper layer of soil that supports plant life.
Plants, especially grass and other ground cover, form an extensive mat of underground roots that hold soil in place. Every time plant cover is removed from the soil surface, the probability of erosion increases. Soil that nature took a hundred years to create can be lost in a single severe storm event. As our climate warms, severe storms are becoming more frequent, along with the increased likelihood that precious topsoil will be lost unless we protect it.
The leading cause of soil erosion in some east-central Indiana counties is running water. Jeff Dukes, director of the Purdue Climate Change Research Center, says that Indiana is getting 5 to 6 inches more rainfall per year than the hundred-year average. When precipitation cannot be absorbed by the ground, runoff will deposit soil particles (sediment) into local waterways. Sedimentation is the No. 1 cause of water pollution in the White River and most other rivers in Indiana. It’s why the river turns brown after heavy rains.
When visitors to our local parks complain that they can’t see the river or the lake because too much vegetation in the way, they may not realize that banks collapse without vegetation or barriers to hold them in place. At Grandview Golf Course in Anderson, IN, trees and shrubs were removed from the river bank beside the fairway of the 10th hole so that golfers could see the river. The result was disastrous; every high-water event collapsed more of the bank and the river was taking short cuts across the fairways. Fortunately, the White River Fund established after the 1999 Fish Kill awarded the city $200,000 to help repair the bank. Today, the Red-tail Land Conservancy holds a conservation easement on the restored habitat along the river at Grandview.
Shadyside Lake and Mounds State Park are both experiencing more foot traffic than usual during Gov. Holcomb’s stay-at-home order. Mounds Park is especially vulnerable to erosion near the limestone bluffs overlooking the river. Trail users who climb up and down the hills, going off trail and carving short cuts in sensitive areas, have no idea how much damage they are doing. By trampling plants that are holding the soil in place, they accelerate the process of soil erosion and degrade the ability of the park to support its unique plant life. Small erosion channels can turn into gullies of bare soil devoid of plant life, forming giant wounds on the earth’s “skin” that are very difficult to heal.
Well-known conservation writer Rachel Carson said, “Conservation is a cause that has no end. There is no point at which we will say our work is finished.” Conserving and protecting soil should be a priority every time we humans plow a field, build a subdivision, construct a road or disturb natural vegetation. Life depends on it.
Sheryl Myers taught biology and environmental science for 34 years and has worked as a naturalist for area parks. She is a founding board member of Red-tail Land Conservancy.