Invading Nature: Exploring the Impact of Invasive Species

The story of Lenape indigenous peoples in Hamilton County and their displacement from their land by white settlers is familiar to visitors of Conner Prairie. But did you know that many of our treasured native plants and animals have been displaced in a very similar way?

The rich heritage of the Lenape people was part of a balance that indigenous cultures maintained with their environment. Fishing, farming, and hunting were all part of a respectful equilibrium between indigenous communities and nature. This balance allowed native plant and animal species to thrive without any species dominating their environment—human or flora and fauna.

This balance, in terms of culture, land control, and the environment, shifted drastically as European settlers displaced the Indigenous inhabitants of Central Indiana and Hamilton County in the early 1800’s. The spread of invasive species into our landscape follows the same story—in fact, some of those very settlers were the first to bring species that would eventually spread and disrupt the once well-balanced ecosystem.

What is an invasive species?

Invasive species are species that are non-native and cause harm to the environment, human health, and the economy. When these non-native species are brought to a new area, they don’t have the limitations that kept their spread in check in their native environment. This allows them to spread rapidly, displacing native species that have been existing in a balanced ecosystem. Additionally, some invasive species have characteristics that actively suppress the growth of nearby species. 

Some invasives brought to the United States by early settlers

When settlers came to the United States and expanded westward, they brought plants, animals, and insects from their homelands along with them. Some of these were for agricultural or forage purposes (onions, wheat, barley), others ornamental (tulips, daffodils), medicinal (lavender, dandelion, chamomile) and some others for food or work purposes (pig and other livestock, horses, even cats and dogs). Many of those species have become ‘naturalized’ meaning that they are outside their native range, but have established self-sustaining populations and, most importantly, have little to no negative impact on local ecosystems. Unlike naturalized species, invasive species do cause damage to local ecosystems by rapid and prolific spreading which replaces native plants.

1745 Mimosa tree, Albizia julibrissin, which is native to Asia, arrived with early colonists to the States as a medicinal and forage plant. The admittedly beautiful pink flowers made it popular in the landscape however, its prolific seed production allows it to spread rapidly and shade out natives.

1868 Garlic mustard, Alliaria petiolata, was introduced by early settlers for medicinal and food uses. It quickly escaped cultivation and is now dominating forest understories across the States. Garlic mustard flowers in the early spring and can be managed by pulling and bagging the plants. You can even make a pesto with the garlic mustard plants.

1890- Starlings, Sturnus vulgaris, were brought over by a group called the American Acclimatization Society in New York who sought to introduce every bird species mentioned in Shakespeare’s works to the USA. Only 100 birds were introduced in 1890, but Starlings are now one of the most common bird species in North America. Indigenous populations and early settlers of this area would never have seen the twisting and swooping flocks of starlings we commonly see today. Unfortunately, starlings are aggressive and take over the nests of native birds, such as bluebirds, flickers, and woodpeckers.

As time has gone on and transportation, shipping, and movement around the world has gotten easier and faster, so has the movement of plants, animals, insects, fungus, and diseases. This means the exchange of potentially threatening species occurs daily. In Indiana, the horticulture trade is the biggest source of invasive species. That means our landscaping choices directly affect the ecological balance and beauty of places like Conner Prairie.

What’s the problem?

When invasive species take over, they displace the native plants that have been growing for hundreds and thousands of years. This is bad because many of our native animals and pollinators have unique relationships with specific plants. If those native plants are eradicated, we lose the associated insects and pollinators that are the foundation of our food webs and ecosystems. Some invasive plants can even cause direct harm to human health (ex. giant hogweed skin burns, barberry and increased tick populations, etc.)

The loss of native species is also damaging to our cultural heritage. The native plants that have grown in an area are important parts of the history and cultural landscape of an area and its people. Invasive species alter the way we interact with our landscape and threaten the integrity of historical sites like Conner Prairie.

What can we do?

Parks departments, schools, churches, neighborhoods, individual property owners, and cultural institutions like Conner Prairie are working hard to remove invasive species and restore ecosystems to their natural balance. There are many ways we can act to support these efforts and there is no better time than now because April is Invasive Species Action Month in Hamilton County!

• Shop Native. Several invasive species are still for sale at big box stores and landscape retailers. Shop smart by seeking out native plants to purchase and know which invasive species in your area to avoid. The Indiana Native Plant Society has a great Plant Finder tool to help you find plants for your yard and a Buy Indiana Natives retailer directory that list retailers who sell natives and no invasives.
• Remove Invasives. Whether you have a woodlot or a small residential yard, you probably have an invasive or non-native plant growing. Check out some of the resources on the Hamilton County Invasives Partnership website to learn how to identify and remove invasives. You can also contact your local Soil and Water Conservation District to get connected with local resources. Here in Hamilton County, we offer invasive species site assessments, management plans, tools you can loan, and even small grants! 
• Volunteer. Local organizations and parks departments need your help removing invasives! Find a Weed Wrangle volunteer event to help remove invasive plants from a beloved property. There are many ways to get involved.
• Learn. Prefer to learn in person? Join us for an in-person workshop on Saturday, April 27, at 11 a.m. at the Carmel Clay Public Library. We’ll be learning about the Dirty Dozen—the top 12 invasive species you are likely to find in your yard. This event is free and open to all.
• Talk to Friends and Neighbors. Spreading awareness is critical to stopping the spread of invasive species. Share this blog, follow @hcinvasives on social media, and share a post, or explain to your neighbors why you are removing that invasive from your yard.

What is Conner Prairie doing?

Conner Prairie covers over 1,000 acres of property along the beautiful White River. Invasive species are a persistent threat. Conner Prairie is working with the Hamilton County Invasives Partnership to map invasive species throughout the property and is dedicated to invasive species management on its land. Learn more about how you can help in removing invasive species at Conner Prairie through volunteer efforts.