Invasive Species in Indiana

Invasive species such as emerald ash borer, garlic mustard, and zebra mussels, have wreaked havoc and have left a lasting mark on the landscape. Species are considered invasive if they are non-native to a particular area, and their introduction causes or is likely to cause economic or environmental harm or harm to human health. For example, invasive weeds can clog waterways, kill native trees and shade out crops and native plants.

Invasive species are a big problem in Indiana, but you can help minimize their impacts. This slideshow will help you familiarize yourself with a few of the invasive species which are trying to take over natural areas in Indiana. These bad plants have the potential to negatively impact water quality, recreational opportunities and drastically alter ecosystem function of the spaces they invade.

If you see any of these invasive species, please report it. It's easy!  Go the EDDMaps website to learn how you can turn your smartphone into a powerful weapon against invasive species.

Leafy spurge

Leafy spurge has already disrupted landscapes out west, and it's now headed east. Once a stand of leafy spurge becomes established, it reduces pasture or grassland productivity. For example, if leafy spurge is present in a hayfield, the hay cannot be cut and moved, resulting in economic loss. Infestations can displace native plants and reduce wildlife habitat.

If you see leafy spurge, report it!

Sericea Lespedeza

Sericea lespedeza is definitely a plague on the prairie. It is arguably one of the most problematic invasive species of prairie landscapes, but sadly this bad plant thrives in a variety of conditions. Sericea produces an abundance of seed: one sericea plant is able to produce more than 1000 seeds, and seeds are thought to be viable for up to 20 years in the seedbank. Let's keep this plant out of our Hoosier natural areas!

Yellow Iris

Yellow iris has the potential to invade our Indiana wetlands and wetland habitats. It does well at the edges of streams and ponds, in open and forested flood plains, and along shorelines. Yellow iris expands quickly via rhizomes, and can form dense stands that can replace and crowd out valuable aquatic plants, such as native irises. Learn how to tell native and non-native irises apart, and help us keep the bad ones out of our wetlands!

Mile-a-Minute Weed

The name says it all. Mile-a-minute weed is a vigorous vine that literally smothers other herbaceous plants, shrubs and even trees by growing over them. Growing up to 6 inches per day, mile-a-minute weed forms dense mats that cover other plants and then stresses and weakens them through smothering and physically damaging them. Sunlight is blocked, thus decreasing the covered plant’s ability to photosynthesize; and the weight and pressure of the mile-a-minute weed can cause poor growth of branches and foliage. Keep this overbearing plant out of Indiana!

Japanese Knotweed

We're seeing more and more Japanese knotweed  in Indiana, and that's not a good thing. The plant, which can grow from three to 15 feet tall, has bamboo-like stems and is sometimes called Japanese bamboo. Japanese knotweed thrives in disturbed areas and, once established, can spread rapidly, creating monoculture stands that threaten native plant communities. Japanese knotweed can tolerate deep shade, high temperatures, high soil salinity and drought. It is one tough customer, and we need your help to keep it from spreading further.

Flowering Rush

What a poser! Flowering rush is an invasive plant that is very difficult to identify when not in flower, because it closely resembles many native shoreland plants. Flowering-rush grows along lake shores and slow-moving rivers. It can be found from the shoreline and in water up to 9 feet deep. Once established, it is very challenging to remove. Flowering-rush competes with native wetland and shoreline vegetation and can crowd out more desirable species. Help us keep this imitator out of our lakes!

Giant Hogweed

Look but don't touch! The giant hogweed plant is one of Mother Nature's nastier creations. The sap on its leaves, roots, flower heads, seeds and stem hairs can cause blistering and scars if they touch bare skin. So let's keep this bad boy out of Indiana!

If you see it, report it!

Glossy Buckthorn

Glossy buckthorn was once commonly planted in this country as a hedge and for wildlife food and cover. It was widely recommended for conservation plantings in the Midwest until folks learned of its darker side. This invasive interloper creates dense thickets and out-competes native vegetation. Its fruit is widely dispersed by birds and small mammals. Glossy buckthorn can be a host for alfalfa mosaic virus and crown fungus, which causes oat rust disease. It has also been implicated as a possible host for the soybean aphid. If we catch infestations early, we can eradicate it.

Amur Cork Tree

In the early 1900s, the Amur cork tree was being planted in the United States in boulevards, parks and residential yards. It wasn't satisfied with its urban environment, and started moving into natural areas. Forests that once were dominated by oaks, hickories and native shrubs are now being overrun by the cork tree. That's not good for our forests, and it's not good for our wildlife: the cork tree berries are less nutritious than the nuts produced by the oaks and hickories. Help keep the Amur cork tree and its substandard berries out of Indiana!

Black Swallow-wort

Now it's personal. A plant that kills monarch butterflies? Black swallow-wort is toxic to certain insect larvae, including those of the monarch butterfly. Should a female monarch lay eggs on swallow-wort, the emerging caterpillars will die. Our butterflies are in enough trouble without this invasive plant, so help us keep it out!

One final reminder: If you see it, report it!  Thank you for your help to keep our natural lands invasives-free!


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