5. Common Privet

As its name suggests, a privet hedge is a familiar sight. The familiarity of this plant, scientifically known as Ligustrum vulgare, makes it difficult to consider it a problem, but it’s on official lists of invasive plants in much of the Northeast and Midwest, from Maine to Pennsylvania.

Privet is widely known, and lots of people grow it because it responds well to pruning and withstands the pollution that typically kills plants in urban settings. However, you’ll be surprised at how fast privet shrubs can grow; they can easily get out of control and become naturalized in the wild.