How to reduce erosion, improve habitat along a waterway

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Vayda squatting in front of tree roots, holding soil together along a creek bed
Vayda squats down to check out how tree roots prevent soil erosion along the creek bank at her grandparents' house. (Sara Welch photo)

The creek in my parents’ backyard is probably one of my favorite features of their property. Even before they purchased the small plot of land they eventually built their house on, I loved the creek. My brother and I would ride our bikes from the old farmhouse we grew up in down to the bridge to flip rocks and catch crayfish, salamanders, frogs and sometimes small garter snakes.

Now, my daughter, Vayda, enjoys the creek, finding deposits of blue clay, fox holes, clams and catching tadpoles. Every spring we’re peeling shoes and socks off as soon as the temperature rises into the 50s, and we’re exploring. Last summer, she even established a little fishing hole for herself near a site we jokingly call her beach because so much sand has washed up in a spot where the creek bends.

In the last couple of years, Vayda has taken an interest in gardening and planting trees, and of course, she wants to plant them near the creek where she likes to spend her time. Two years ago, she transplanted a sugar maple that she grew from seed along the edge of the creek in the spring. Last spring we had to move the struggling sapling in four of five feet as the buffer between it and the water had eroded away from an unusually rainy spring and early summer.

Vayda’s tree got me thinking about the health of the creek bank, the types of trees and plants that grow along it and what could be done to improve it.

Benefits of a vegetative bank or riparian buffer

A vegetative bank or riparian buffer is an area between a waterway and a field, yard or other land use that houses native trees, shrubs and grasses that are tolerant to flooding and saturated soils. These areas create habitat for terrestrial wildlife, enhance aquatic habitat, filter out potential pollutants, provide flood control and reduce soil erosion and undercutting of banks.

Helping wildlife. Areas along stream banks provide habitat for many species of endangered and threatened plants and animals as more than 70 percent of terrestrial animals use these areas at some point during their lives, making them extremely bio-diverse. Planting native trees, shrubs and grasses provide food, shelter and cover for terrestrial animals visiting the waterway.

Aquatic life is also improved by riparian buffers through the filtering of pollutants and benefits provided by native plants. Clean and sediment-free water is important for fish and aquatic insects to be able to breathe and establish spawning sites. The shade provided by deciduous trees keeps the water cooler in the summer and limits algae growth. Additionally, fallen leaves, woody debris and other organic material provide food and habitat for a number of aquatic species.

Filtering pollutants. Riparian zones can absorb a lot of runoff and protect surface water. Native plants help filter pollutants before they can reach waterways, which keeps the water cleaner and reduces algal growth. They act as a buffer to slow runoff from fields, roads, yards and urban areas. Additionally, they can remove nutrients, sediments and even block pesticides from reaching waterways.

Providing flood control. The soils here act as a sponge and can absorb a lot of water. The soils combined with the vegetation can take the excess water on floodplains by increasing water storage capacity and reducing the risk of erosion. When the water level retreats the groundwater in the soil will follow opening more storage for the next flood.

Reducing soil erosion and undercutting of banks. In addition to the soil’s increased storage capacity reducing the risk for erosion, trees growing on the river and stream banks will help stabilize the banks to reduce streambank erosion. 

Planning your riparian buffer

The first step is to determine the size of the buffer you need based on your local soil and water conservation district’s recommendations and the amount of water that runs off the adjacent land.

Measuring and defining your riparian buffer:

  1. Measure the depth of your riparian buffer, starting at the edge of where the bank drops off and measure at least 25 feet back from that point. Your buffer should be deeper if your local soil and water conservation recommends it or if there’s a lot of runoff from that land next to it that needs to be filtered before it reaches the waterway.
  2. Measure the length of the stream along the edge of your property to determine the total space you’re planning on converting so you can get an estimate for the number of native plants you’ll need to cover the space.

Choosing plants for a riparian buffer

You’ll want to choose a variety of trees, shrubs and native grasses to plant in your riparian buffer to ensure biodiversity and better protect your riparian buffer from being wiped out by a specific pest or disease. It’s also good to choose trees of varying sizes that provide food and shelter to a variety of wildlife. The long-term goal for your riparian buffer is to have trees and shrubs of various generations, so plan to continue to add to it year after year. 

Other tips:

  • Don’t forget to cover the ground with multistemmed shrubs and native grasses.
  • Don’t plant exotic plant species as they don’t add to the ecosystem. Native trees and shrubs are more likely to survive and will provide more ecological benefits.
  • Don’t plant invasive species as they can crowd out other plants or climb and smother trees. Additionally, it’s a good idea to remove invasive species before planting native species.
  • Don’t plant turf grass. It’s not good at absorbing stormwater and requires a lot of maintenance.
  • Don’t use fertilizers or pesticides in your riparian buffer. It kind of defeats the purpose and introduces more pollutants to the nearby stream.
  • Trees and shrubs planted closest to the stream should be species that are suited to wet soils.

Trees and shrubs for wet soils

Large Trees

Red Maple
Silver Maple
River Birch
Sycamore
Cottonwood
Swamp White Oak
Pin Oak
Bur Oak
Sweetgum

Medium Trees

Box Elder
Black Gum
Black Willow
Weeping Willow
Beech
Chokecherry

Shrubs

American Hornbeam
Silky Dogwood
Sumac
Buttonbush

Trees and shrubs for well-drained soils

Large Trees

Black Maple
Yellow Birch
Shagbark Hickory
Common Hackberry
Kentucky Coffeetree
Butternut
Black Walnut
Tulip Poplar
Cucumber Magnolia
Wild Black Cherry
Red Oak
Hardy Catalpa

Medium Trees

Ohio Buckeye
Black Gum
Quaking Aspen
Eastern Redbud

Shrubs/Small Trees

Allegheny Serviceberry
Common Pawpaw
Flowering Dogwood
Blueberry

Grasses and herbaceous plants

Some common Ohio riparian grasses and herbaceous plants include palm sedge, switchgrass, big bluestem, soft rush, viola, monarda, blue flag, trillium, turtlehead, swamp milkweed and Jack-in-the-pulpit.

Related Content

How to determine if your creek is healthy

Resources

Woods for Waters: A guide to planting riparian buffers for healthy streams

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