Japanese Barberry

Japanese barberry is one of the invasive species that the State of Maryland currently considers the most troublesome. Learn more below.

Japanese Barberry
James H. Miller, USDA “Japanese Barberry,”
October 1, 2010 via Forestry Images, Creative
Commons Attribution.

Description

According to the Plant Conservation Alliance's Japanese Barberry page, the plant was introduced as an ornamental in 1875, and continues to be sold in the US today. However, because of its invasive tendencies, the Alliance requests consumers to stop planting it.

Japanese barberry is a shrub that can grow up to eight feet tall. It has sharp spines, blue-green leaves, pale yellow flowers in the spring, and bright red berries from late summer through the winter.

The Threat

The Plant Conservation Alliance says that Japanese barberry has acquired an ecological advantage because white-tailed deer avoid eating it. Escaped Japanese barberry spreads rapidly, forming dense thickets that crowd out native plants. Japanese barberry also adversely affects the balance of acid and nitrogen in the soil.

Control and Removal

Japanese barberry produces numerous berries that are spread by birds. The Alliance recommends pulling out new plants early in the spring, before the berries have had a chance to form. The spines are sharp, so volunteers are advised to wear heavy gloves for this work. Large infestations can be treated with herbicides such as Roundup®.