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TEDx VernonAreaLibrary

An invasive species, Buckthorn, is wiping entire ecosystems, destroying necessities for humans and wildlife, damaging infrastructures, and changing our iconic landscapes. Allison Frederick describes how to stop this invader in our own backyards. As the assistant public affairs manager for the Lake County Forest Preserves, Allison Frederick's forestry and natural resources background and passion for land stewardship make her an asset to the conservation agency. She believes that we can join forces to take major action against environmental challenges, starting in our own backyards. This talk was given at a TEDx event using the TED conference format but independently organized by a local community. Learn more at


The spread of invasive species is recognized as one of the major factors contributing to ecosystem change and instability throughout the region. Invasive species have the ability to displace or wipe out native species, alter fire regimes, damage infrastructure, and threaten human livelihoods.

In Lake County, the invasive species European buckthorn (Rhamnus cathartica) now accounts for 42% of the tree canopy. We aim to eliminate buckthorn from all forest preserves and reduce buckthorn by 50% countywide within 20 years by:

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    Step One

    The first step in buckthorn removal is proper identification. Buckthorn is an invasive species of shrub or small tree, reaching up to 30 feet high.

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    Step Two

    In the understory of many woodlands, yards, and neighborhoods, buckthorn often grows in dense hedges or thickets, staying green until late fall.

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    Step Three

    Buckthorn’s oval, shiny leaves have prominent veins and a slight curving tip. They grow one to four inches long. Pale green-yellow flowers appear July through September.

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    Step Four

    Buckthorn produces quarter-inch, glossy black fruit by September. Birds and other wildlife eat this fruit and disperse the seeds, spreading buckthorn into new areas.

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    Step Five

    Buckthorn bark is gray-brown with small, horizontal white-gray lines called lenticels. Common buckthorn bark can peel and look shaggy with age.

Allison Frederick, Assistant Public Affairs Manager, introduces the major steps of buckthorn removal in your backyard.