Invasive plants endanger Maryland’s native wildlife. A 2024 study ranked Maryland 19th among states for invasive species, and seventh for invasive plants.
Invasive plants are plants that have come from a different ecosystem and have no predators in the new ecosystem, which leads to them taking over places where native plants once grew.
The Nature Conservancy has said, “In the U.S. alone, invasive species cost over $120 billion annually in damage and control, and the cost they inflict on our natural heritage is immeasurable.”
There are different ways to remove invasives, each with different price points and environmental impacts.
“Three broad categories cover most invasive plant control: mechanical, chemical and biological,” said District Ranger Christopher Mattrick in his booklet “Managing Invasive Plants: Methods of Control.”
When it comes to invasives, control isn’t always easy. For some species, like English ivy, leaving even part of the stem can allow the whole plant to regrow.
Master gardener Betsy Kingery gave advice on who to contact if you see invasive plants in any state parks, explaining how, “The parks have their own team, but there is a wonderful group called the weed warriors, who are trained on what to pull and what not to pull, and they go into the parks, with the parks’ permission, with volunteers.”
If you are unsure of what to keep an eye out for, the University of Maryland has a list of all the invasives in Maryland, along with pictures to help identify them
“Look out for porcelain berry, which are the vines that are sort of draping all of the trees, Japanese knotweed, and burning bush, which is also called winged euonymus, and honeysuckle, Japanese honeysuckle,” said Kingery.
Just because invasives can spread quickly, that doesn’t mean that you can’t out-compete them. One of the best ways you can prevent invasives from growing in gardens is by planting a native garden. Some native ground covers include Jacob’s ladder, green and gold, and sedges.
Kingery explained, “The best way to prevent invasives in your garden is to plant a lot of ground covers and then plant other taller plants on top of that.”
