Ask the Indiana NRCS Expert: Invasive Species

What is an invasive species and are there common ones in Indiana?

Species that are not native to a local ecosystem and whose introduction is likely to cause economic or environmental harm or harm to human health are considered invasive species. In Indiana, we have invasive plants, animals, insects and diseases. For USDA’s Natural Resources Conservation Service, most of our efforts are focused on invasive plant species. Some common invasive plants in Indiana include multiflora rose, Asian bush honeysuckle, autumn olive, burning bush, tree of heaven and Japanese stiltgrass. 

How do invasive plants impact the environment?

Invasive species have a tactical advantage within the environment. Native species have co-evolved with local predators, diseases and the space they occupy within the environment. Invasive species are not impacted by local predators or diseases and tend to capitalize on open areas or disturbance within the environment. With this tactical advantage, invasive species out compete native species, disrupt pollinators, provide poor food resources for wildlife and even change soil chemistry. 

Why not just let them grow if they will never go away?

The cost to native diversity is too high to let invasive plants spread unchecked. Losing the diversity and integrity of our native ecosystem has future ramifications we don’t understand. The best defense against invasive species is to not introduce any new ones. But once they have been introduced and taken hold, we can give native plants, animals and pollinators a better chance to survive if we remove invasive species. By removing and keeping invasive species out, we allow native species to take over and reoccupy the space the invasive plants have occupied, soil chemistry reverts to what it was, local wildlife thrives and native pollinators benefit from the native pollen sources.

How do you treat or control them?

The best way to treat invasive plants is by using an integrated pest management system. This sounds fancy, but it just means that you use the most effective cultural, mechanical, chemical or biological method to exploit a weakness in the invasive plants to kill or control them. A cultural practice would be cleaning boots and equipment before going into or leaving a natural area to prevent invasive seeds from spreading from one place to another. Mechanical control would be hand pulling small infestations of invasive plants before they go to seed. Chemical control would be using the right herbicide at the right time in the right amount to kill an invasive plant. Biological control is typically not something a landowner can do, but with some invasive pests we can introduce an insect or disease that will kill the invasive species. The key is having a plan to control invasive plants, be persistent in treatment and be patient knowing it will take some time to get them controlled.

What programs does the NRCS have to help?

Indiana NRCS collaborates with SICIM (Southern Indiana Cooperative Invasive Management) to help establish Cooperative Invasive Management Areas (CISMAs) at the county level. By working with SICIM Regional Specialists and your County CISMAs to develop a plan that includes controlling invasive plants many landowners are eligible for Farm Bill programs that assist with the control of invasive plants. Invasive plants don’t care if they grow on your property or your neighbor’s property so it is critical to have local engagement and as many landowners as possible controlling invasive plants to reduce their ability to spread, protect soil resources and limit damage to native ecosystems.

Who should I contact if I have questions about dealing with invasive species?

The effort to control invasive plants has grown tremendously in Indiana and so have the resources to deal with invasive plants. You can check out the resources page for SICIM (Southern Indiana Cooperative Invasive Management) at www.sicim.info. They have statewide resources to help you find someone to visit with you on your property, to walk and talk about invasive species, and develop a control plan. This will help you grow in your understanding and identification of invasive plant and help you be successful and efficient in controlling invasive plants on your land.