Invasive Plants
What is an Invasive Plant?
An invasive plant is a plant that is not native to the ecosystem and will likely cause harm to the environment or to human health.
So, What’s the Big Deal?
Maine is home to roughly 2,100 plant species and about 2/3 of them are nonnative or invasive. When invasive plants take over, they crowd out the native species that wildlife depend on for food, nesting, and shelter. This loss of habitat disrupts the ecosystems that define Maine’s natural character. Protecting our landscapes means preventing invasives plants from replacing the native communities that make Maine, Maine.
What are the Worst of These Invasive Plants in Freeport?
for more information click on the V-symbol to learn more about each invasive plant
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A woody vine that wraps around other trees to climb into the canopy with red berries in the fall and winter and white, green leaves in the spring and summer.
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A tall shrub that can grow to about 10 feet by 10 feet. It produces fragrant white flowers in the spring and small red berries in the summer. It often grows in thick and can be difficult to cut through. There are lots of different types of honeysuckle in Maine, some are invasive and some aren’t, a good way to know the difference is to cut open a stem and look inside. The native spices have solid pith, the invasives are hollow.
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Knotweed is extremely durable and strong when it comes to regrowth. Knotweed has adapted over the years to be able to grow through things like gravel, tar, and cement. It originated in Asia, mostly growing on volcanoes. You can recognize it by its hollow, bamboo-like stalks.
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Common and Glossy Buckthorn is a small tree that can grow to 25 feet. They grow in densely and can be easy to mistake for a native sapling. Common Buckthorn has dark green egg-shaped leaves with jagged edges, small spines at the end of most twigs, and a matte appearance. Glossy Buckthorn has smooth leaves with no spine.
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These shrubs can grow up to 6 feet tall and wide. They grow yellow flowers in May and red berries in late summer that last through winter. The plant often spreads when birds eat its barriers and scatter the seeds.
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It is highly invasive and grows in thick mats overtaking the natives around it. It thrives in moist areas like forests and stream banks. They are long and bamboo-like with light green leaves and stems. They have a strong silver stripe down the mid-rib.
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Can grow up to 20 feet tall with many arching branches. It grows small white flowers in May and June and sharp thorns year-round. They thrive in full sun but are shade tolerant. They are often found on forest edges and fields. They can be very hard to move/destroy due to their thick brambles and thorns.
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A flowering plant native to europe, asia, northern afirca, and estern astralia. It is often mistaken for Fireweed, a native wildflower which also typically has long slender shape with purple flowers.
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Burning bush can be highly invasive. Fall is a great time to identify it as the leaves change to a bright red! Historically, it has been planted as an ornamental because of its beautiful autumnal colored leaves. It can take multiple years of re-mowing to get rid of it.
Learn More:
Watch Amanda Devine, Director of Stewardship at MCHT and an FCT volunteer who manages Invasive Plant Management, talk about recreational invasive species management in an FCT virtual workshop.
How You Can Help Care for the Native Landscape:
Maine’s forests, fields, and backyards thrive with native plants. Whether you are tending to your garden or exploring local trails, there are simple and meaningful ways to support a healthier landscape.
Remove Invasives Responsibly
Invasive plants grow quickly and outcompete the species that wildlife depend on. Tackling them doesn’t have to be overwhelming, small and steady efforts make a real difference.
For effective removal:
-Pull younger plants when the soil is damp and roots come up easily
-Cut larger shrubs or vines at the base and return throughout the season to prevent regrowth
-Wear gloves and protective clothing; many invasives have thorns or sap that can irritate skin
-Clean tools and boots after working to avoid spreading seeds.
Proper disposal prevents invasives from re-rooting or spreading seeds. Never put invasive plant material in compost as they will continue to grow. Instead you can hang the plant material on branches nearby the location site until they dry out to minimize spread of berries or seeds. Then, bag the plants for proper removal at a permitted site or burning when safe and permitted.
The Freeport Recycling Center cannot accept invasive plant matter, but the Riverside Recycling Facility in Portland does accept it for a fee.
Report Invasives
If you spot an invasive plant, you can report it on the iMapInvasives Database. These reports help natural resource managers track where invasive species are spreading in Maine.
Plant Native Plants
Looking for alternatives to help regrow Maine’s native plant population? The Wild Seed Project offers an excellent resource library and list of nurseries that sell native plants suited to Maine’s ecosystems.
Spread the word about invasives and native plants with your neighbors and friends to help decrease the popularity of invasive ornamentals like Burning bush.
About the author
Calla Wiederkehr is an 8th grader at the Maine Coast Waldorf School as well as a pig farmer and cheese maker. Their family lives on 65 acres of conserved farmland under an FCT easement. They started volunteering at Freeport Conservation Trust for a school project in the fall of 2025.