Beware of invasive shrubs sold at garden centers

Most varieties of Japanese barberry planted in gardens are burgundy but they can also be green (or a combination of both). Small spoon-shaped leaves and thorns are other identifiers. This plant has flowers budding. (Courtesy photo)

Most varieties of Japanese barberry planted in gardens are burgundy but they can also be green (or a combination of both). Small spoon-shaped leaves and thorns are other identifiers. This plant has flowers budding. (Courtesy photo)

Some shrubs that are commonly found at garden centers are actually invasive species. They may appear harmless but have the potential to cause widespread environmental harm when they escape cultivation.

Invasive shrubs are popular because they tend to grow fast, leaf out before other plants, and produce a lot of berries. Unfortunately, these characteristics also allow them to take over natural areas.

Invasive shrubs like honeysuckle can form dense thickets are that are incredibly difficult to remove. They also crowd out native plants and degrade wildlife habitats. Invasive honeysuckle can be mistaken for native species of honeysuckle, but non-native varieties can be distinguished by their hollow stems.

Other shrubs may even threaten human health, such as Japanese barberry, which harbors deer ticks that can carry Lyme disease.

"If you have an invasive shrub growing in your yard, you can help improve habitat for native wildlife by removing it," according to a news release. "The best time to remove invasive shrubs is from late summer until the first hard frost or on days when the sap is flowing. This occurs on days when the temperature reaches between 40-45°F during the day and drops to below freezing at night."

Cutting down the shrub and applying a concentrated glyphosate or triclopyr to the freshly cut stump is an effective means of control. There will likely be resprouts, so follow up treatment may be necessary.

For assistance identifying invasive species or guidance on buying herbicide, contact NCCISMA at 231-429-5072 or email vicki.sawicki@macd.org. You can also visit www.NorthCountryInvasives.org. To learn more about native alternatives to invasive shrubs, visit the Midwest Invasive Plant Network at www.mipn.org. Brochures on native plants can be found at your local conservation district.