Our mission is to conserve all species of native plants and animals that are found on the field station, especially those whose populations are in decline.

The field station covers a mosaic of different habitat types (upland forest, meadow, shrub field, wetland, vernal pool, stream, and pond), each of which is home to a different community of plants and animals. There is so much biodiversity here! 189 species of birds have been observed and over 1,200 species have been documented on the field station.

Succession refers to a sequence of changes of an ecological community over time. Usually, a field is succeeded by shrub fields, which are succeeded by young forests, which are succeeded by mature forests. Early successional habitats are disappearing as a result of development and the invasion of nonnative plants. Unfortunately, many species of birds, including Yellow-breasted Chat, American Woodcock, Field Sparrow, Prairie Warbler, Grasshopper Sparrow, Blue Grosbeak, and Eastern Meadowlark, rely on these habitats. 26% of the birds listed as Tier 1 (Species of Greatest Conservation Need) by the VA State Wildlife Plan are early successional species. Across North America, grassland birds are declining faster than birds that live in any other habitat.

Our grasslands on the left and our shrublands on the right.

In 2019 we started a major project to restore 110 acres of what has been used as a cattle pasture to a native grassland. The first step in establishing a native grassland is getting rid of the nonnative plant species; we will do this by using herbicides and repeated discing (an organic alternative similar to plowing). Historically, grasslands and shrublands in eastern North America were maintained by fires, but humans have dramatically reduced fire frequency. Now, humans have to intervene to maintain this vital ecological system. Once native plants are established, we will maintain the grassland by mowing or prescribed burning. We will test eight combinations of establishment and management methods in order to figure out how best to help declining native species. Virginia Working Landscapes and the Oak Spring Garden Foundation will replicate this experiment on their respective properties. Having three properties involved in the experiment will dramatically improve the statistical significance and general applicability of our results.

We will measure the effectiveness of each treatment with biodiversity and soil surveys. To get a baseline understanding of the state of the pasture, volunteers from the Piedmont Chapter of the Virginia Native Plant Society quantified the relative abundance of all plant species in our pastures over the course of the summer of 2018 (you can find the full list here). Starting in the summer of 2018, volunteers and staff members have conducted regular bird, butterfly, and plant surveys, all of which will continue in the years to come. Our findings will be used to guide our future restoration projects and educate local landowners.

Prescribed burn in our shrublands in early 2019

We also use prescribed fire and mowing to maintain 100 acres of shrublands on our field station.

Many of our habitats are threatened by invasion by exotic species of plants. Some of the biggest culprits are Autumn Olive, Oriental Bittersweet, Japanese Honeysuckle, and Tree-of-Heaven.

Exotic species serve as host plants (food for insect larvae) for very few native insects because insects have adapted to the leaf chemistry of specific native plant species for hosts. Exotic plants, such as Autumn Olive, also provide inferior food sources for birds, compared to native plants.  Exotic plant invasions are therefore having a dramatic negative effect on populations of native animals.

To counteract this problem, we are removing exotic plants from our fields and forests in an effort to create higher quality native habitat. If you’re interested in helping out, you can find upcoming volunteer days on our calendar. Thank you!

Executive Director Bert Harris and a group of volunteers work on removing Autumn Olive.

Thanks to the generous support of the Warrenton Garden Club, we were able to install a native plant garden at the farm house in the fall of 2018.  The garden serves as habitat for native animals and it allows us to teach visitors about the value of native plants right off of our front porch. Most programs at Clifton start at the farm house so the garden engages visitors as soon as they arrive. After giving the garden a year to grow, in 2020 we will begin a research project to study which species of insects use the garden for host plants, nectar, and pollen.

Summer campers learn about the plants in our native plant garden