Some weeds are so persistent, destructive, and difficult to eradicate that they have been designated as noxious. Maryland has a noxious weed law that requires landowners to control Canada thistle, johnsongrass, and shattercane on private property. For effective control, both the seed and the root system of these weeds must be managed by mowing, cultivating, or treating with approved herbicide.
Plants that are widely known to out-compete native plants and quickly take over natural areas, but have not been designated as noxious weeds, are called invasive plants.
Many common invasive plants are used in landscapes. Eradicate invasive plants on your property and before you purchase a new plant, be sure it is not a listed invasive plant.
Here are a few examples of common invasive and noxious plants:
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| Japanese Stiltgrass Microstegium vimineum |
English Ivy Hedera helix |
Oriental Bittersweet Celastrus orbiculatus Thunb |
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| Phragmites/Common Reed Phragmites australis |
Chinese Silvergrass Miscanthus sinensis Anderss. |
Multiflora Rose Rosa multiflora Thunb. ex Murr. |
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| Tree of Heaven Ailanthus altissima |
- Identify the invasive plants in your yard and take action to rid your yard of them. Many invasives can be controlled by hand pulling. See Plant Invaders resource book for more information on identification and eradication techniques.
- Replace areas full of invasives with native plants. Native flora provide crucial habitat to native fauna and require much less maintenance.
- Plant a diverse selection of native plants to support a larger number of Maryland species.
- Volunteer with a local environmental or watershed organization to remove invasive species in parks and communities in the area.
- Never travel with firewood from home; buy wood when you reach your destination. Invasive species such as the Emerald Ash Borer have been spread this way throughout Maryland causing wide destruction of native ash trees.
