By Catherine Plaisant (plaisant@umd.edu) All photos by Catherine unless indicated otherwise.

With the planting of an interpretive sign at the end of December, the Greenbelt Community Conservation Landscape and Demonstration Project is reaching completion.

The interpretative sign

A team of neighbors living near 65 Ct. Ridge Road worked together – and with Greenbelt Homes Inc. (GHI) – to obtain a Chesapeake Bay Trust Community Engagement and Restoration Mini Grant.  This allowed us to install a garden of native plants and crescent-shaped berms to catch stormwater running downhill.
You can see the results at 65 Ct. Ridge Road, across the street from Greenbelt Elementary School.

Our goal was to mitigate stormwater issues at the source, support pollinators, and provide a demonstration site showing examples of things you can do yourself.  Installation was completed entirely by volunteers. Volunteers also maintain the project, which is installed on a small common area in GHI.

The (partial) team of volunteers, in front of the sign.
Top row: Lin Orrin, Jonathan and Anton Rytting, Julius Green, Kathy Merritt.
Bottom row: Megan Rytting, Catherine Plaisant and John Klinovsky.  Photo credit: Julie Magness
Other lead volunteers were Zach Conron and Cary Coppock. The GHI project manager was Peter May.

Why do this?

We first had quite ambitious plans to seek a large grant and improve a much larger area on a very steep hill where heavy runoff flushes toward a creek, but we decided to start small, and literally “get our feet wet,” by applying for a mini-grant to address an area at the top of the hill. Before the project started the area looked awful, with bare spots and active erosion taking dirt down the sidewalk in the rain. The reduction of stormwater runoff may be limited, but rainfall now infiltrates onsite during an average storm. It is a good location for a demonstration project and introduces these concepts to middle school students (waiting for their bus) and elementary school students and their parents arriving at school.

 BEFORE:  Several trees had been recently lost, bare soil was everywhere, and erosion significant.

AFTER:  By summer, the trees, shrubs and wildflowers were planted, watered and started to thrive.
A small fence marks the area, protecting the planting from dogs and humans.

What is a conservation landscape?

A conservation landscape is a garden that improves water quality, promotes and preserves biodiversity, supports native species, and provides wildlife habitat.

The old way of dealing with stormwater was to make the water go away as quickly as possible, using drains, culverts, and even concrete channels.  The speed and amount of runoff led to damage in our streams and waterways.  Now we know that it is best to slow down the water and to let it infiltrate in the soil as much as possible before it reaches the streams.  The swales which are found in GHI collect water during a storm (and infiltrate it within a day or two) are useful features to have (very ahead of their time), but we will need many more similar features to help our streams recover and deal with stronger storms.

What techniques were used?

We used two techniques to accomplish our goal on this little hill with about six feet of elevation drop:

1. We built crescent-shaped berms that retain water onsite, so it has time to infiltrate.  Berms could also be seen as small dikes, bioswales, or ways to terrace the slope. You can see the effect most clearly near the interpretative sign, or from the bottom of the slope.
2. We replaced a large portion of the remaining grass and planted trees, shrubs, and wildflowers. They slow down the water, their roots guide the water down into the soil, and evapotranspiration also helps move water back to the air.

The berms under construction, covered by stapled burlap to protect them.

Diagram of the berm design

Now, rainwater remains on site, and infiltrates quickly behind the berms, thanks to plants and amended soil.  Plants above the berms have been selected to tolerate wet soil.

Video

This video shows our volunteers at work installing the berms and plants.

Why use only native plants?

The grant mandated the use of native plants from the Chesapeake Bay region in this demonstration project, and there are good reasons for that.

It is not that introduced non-native plants are bad plants (they are not, unless they are invasive) but today insects and pollinator numbers are dropping rapidly, and restoring the native plants that have co-evolved with them will allow these important species to survive in the future.

Native plants are those plants that occur naturally in a region in which they evolved. They are the ecological basis upon which life depends, including humans. Without them and the insects which co-evolved with them, the birds, animals (including humans) cannot survive.

For example, it is true that we help pollinators by planting non-native flowers which provide pollen and/or nectar to feed the adult pollinators, but most pollinators will not be able to reproduce without native plants, because their larvae or caterpillars only eat the leaves of plants they evolved with over millions of years.
Without pollinators: no trees, no food, no life on earth.

Similarly, we do help adult birds by giving them seeds, which is great, but chicks do not eat seeds… They are fed soft juicy caterpillars.  So, without enough native plants around and the insects that eat them, the birds have a hard time reproducing at all, or they have fewer chicks, and slowly disappear.  Research has shown that yards that include more than 70% of introduced non-native plants were not able to sustain families of chickadees.  Every native plant in a yard helps, and the simplest way to get started is to replace a small portion of the lawn with native plants.

For more nuanced explanations, and information on how you can have a powerful impact by planting natives in your yard, watch this VIDEO from Doug Tallamy “What’s the rush?”, and check the Homegrown National Park.

FAQs 

The project webpage provides the plant list and maps of our design, and answers frequently asked questions such as:

• How did you build the berms?
• Could digging berms hurt nearby trees?
• How did you choose the plants?
• Where did you get them?
• Where did you get the plant labels?
• Why did you use wood chips instead of shredded mulch?
• Why plant a white oak there? Why is it caged?
• Who was involved?

What’s next? 

We dream of being able to apply what we learned to a larger area in the future, but in the meantime, we are happy to give tours of the project and explain what we did.

Of course, we hope that you will use some of the ideas in your own yard.

Contact me at plaisant@umd.edu if you have any questions.

Zach Corron (who coordinated all the volunteer activities) and Catherine Plaisant describe the project to Stephanie O’Brien (on the right).  Photo credit: John Klinovsky

Thank you to all sponsors and volunteers!

This project is made possible by a Chesapeake Bay Trust Community Engagement and Restoration Mini Grant, as part of the Prince George’s County Stormwater Stewardship Grant Program.

The team learned so much while preparing the proposal, from so many people.

We thank the staff from the Anacostia Watershed Society and Nature Forward (formerly the Audubon Naturalist Society), the GHI Woodlands Committee and the GHI Stormwater Management Subcommittee, Mary-Pat Rowan, and many others who provided feedback and suggestions on the design. Finally, we thank GHI’s Stormwater Management Program Administrator, Peter May, for providing feedback on the design and for serving as GHI project manager. We thank Jill Connor and the PTA of the Greenbelt Elementary School for organizing a Saturday workday so that children could help us plant.

Nearby neighbors from Ridge, Laurel Hill and Research Roads have been involved in the project in many ways. Zach Conron coordinated our team of neighbor-volunteers. Lin Orrin helped write the proposal and coordinate with the elementary school. Cary Coppock brought the idea of crescent berms. Kathy Merritt is serving as our official GHI Volunteer Caretaker for the area and leads the maintenance effort. John Klinovsky, Julius Green, and the Rytting family were hardworking regular volunteers. Catherine Plaisant worked on the overall design, plant selection and acquisition, overall coordination of the installation, project website and video. Countless other adults and children living nearby made themselves available to help, but also to learn from the project.