Editor’s note: hello readers, Brett Peto here. Guest author Pati Vitt, Manager of Restoration Ecology at the Lake County Forest Preserves in northern Illinois, is back with the second of her three-part series about our research project to restore 180 acres of former farmland within Grant Woods Forest Preserve using a climate-adapted, regionally sourced native seed mix.
This winter, we planted 800 pounds of native grass seed from southern Illinois and Kentucky in Grant Woods. We hope this will help us understand whether we should source native seeds from further south to make our future restoration projects more resilient to climate change.
Native seeds from Kentucky, for example, may possess adaptations in their genes that help them better survive heat and drought than seeds from Illinois. In the years ahead, researchers will gather and assess data to determine whether one group of seeds fared better than the other.
At the same time we’re spreading seeds, grounds crews are also removing invasive trees and shrubs from hedgerows and woodlots within the project area this winter.
All of these steps require an understanding of ecosystem restoration—how we get a natural area back on the path to recovery from human activity. Pati will take the reins from here.
Guest post by Pati Vitt
Just as the COVID-19 pandemic was starting to grip the world, another global milestone was occurring: The United Nations declared 2021-2030 the “Decade of Ecosystem Restoration.” The official launch date coincides with World Environment Day on June 5, 2021. In an effort to ensure that both people and nature enjoy a sustainable future, it represents a worldwide strategy to stop and reverse habitat degradation across the planet.
According to the Society for Ecological Restoration, the gold standard result for an ecological restoration project is an ecosystem that’s on a self-organizing trajectory to full recovery from human activity. What does that mean? It means little to no human intervention or management is necessary to ensure the health and resilience of that ecosystem. However, there’s a lot of work to be done to set a degraded, or highly altered, ecosystem back on that path. When you visit a preserve and see large pieces of equipment at work, they’re usually in use with an eye toward doing just that.
The intensity and frequency of restoration work required depends where along a spectrum a particular natural area starts. An area with low impact might be something like a remnant prairie, which will require little management except for the restoration of controlled burns or the reintroduction of native grazers such as bison (Bison bison). On the other end are those lands most in need of intensive restoration, like former agricultural fields. Generally, the more altered the landscape and the more human activity present there, the more intervention is needed.
In the Midwest, many farm fields have been engineered to increase crop yield. This is often done by changing the original hydrology of the habitat with drain tiles, so what was once a wetland becomes cropland. Drain tiles are perforated pipes laid below the soil surface, effectively lowering the water table to encourage root growth of planted crops.
As you might guess, drain tiles are a significant alteration of the original environment. This alteration means that restoration of former agricultural lands can be quite complex. Several steps are often needed, and each step requires decision-making.
One factor to consider is how recently the area was farmed. A field that lies fallow for a long time is referred to as an “old field.” The natural process of ecological succession might push the habitat toward one dominated by native plant species that are generalists. Generalist plants can grow in many settings and aren’t very particular about habitat quality. When a farm field goes fallow, these native plants may disperse themselves into it from adjacent areas.
But invasive shrubs and trees can dominate an old field, as well. Invasive plant control can be the first step in a restoration. It may be accomplished with controlled burns, physical removal of woody invasive plants, herbicide application, or all of the above. If only herbaceous (i.e., plants with non-woody stems), invasive species are involved, you might plow the field to allow new native seed to establish rapidly. If invasive species are relatively sparse, as they might be in a newly fallow field, one strategy could be over-seeding the field with fast-growing, native grass species. Following seeding, crews would then selectively apply herbicide to reduce invasive species abundance and boost the success of the newly planted grasses.
Once those grasses are well-established, perhaps within a year or two from seed, the next step is to add herbaceous species such as goldenrods, asters and legumes to diversify the plant community. In the very early stages of a restoration—the establishment phase—continuing to control invasive species is critically important. Frequent control measures will occur for about five years as native plants become well-established. The intensity and frequency of control, though, will decrease over time.
Many farm fields have hedgerows that grow between them. Hedgerows may contain trees, shrubs and fences. They’re variably used to mark property ownership boundaries, control where livestock wander, or act as a windbreak. Removing hedgerows increases connections between fields and reduces habitat fragmentation. Depending upon the size of the trees, heavy equipment may be employed. One common piece of equipment called upon for this task is a skid steer with a Fecon mower attached.
The Fecon mower attachment is ideal for shredding and mulching woody material very quickly. Large areas of invasive buckthorn (Rhamnus cathartica) can be removed efficiently by this tool. The skid steer may be equipped with large wheels for versatile movement, or it could have tracks that reduce damage to the soil by distributing the weight of the machine over a bigger area. An additional way to avoid damage is to limit the use of a skid steer to times of year when the soil is very dry or when the ground is completely frozen.
At Grant Woods this winter, we’re removing invasive trees and shrubs, including buckthorn, box elder (Acer negundo) and white poplar (Populus alba), often confused for birch trees. Our end goals are to open up the tree canopy to encourage oak regeneration, and to support a diverse community of native shrubs and herbaceous species beneath the oaks that remain. We’ll plant additional trees and shrubs, which will provide habitat for birds and other animals. Once the restoration is complete, the project area will be continuous habitat.
As you can see, restoration projects are long-term endeavors, requiring detailed planning and execution to successfully set a natural area back on the path to recovery. Site history, current flora and fauna populations, hydrology, and more must be considered. This project at Grant Woods is no different. But it also has the added component of climate change research that’s important for the future health of Lake County’s natural areas.
Results will not reveal themselves overnight—plants take time to grow from seed, of course—but we’ll be here to document and share them as they happen. Until then, there are some simple ways to fight climate change in your daily life.
Editor’s note, part two: hi there, Brett again. There’s more to this story. Keep watch for the third and final post later this year. And learn more about this research project on our website.