Pennsylvania phasing in ban of invasive Japanese Barberry

HARRISBURG, Pa. — The Pennsylvania Department of Agriculture added Japanese Barberry, or Berberis thunbergii, to a list of noxious weeds — plants that cannot be legally sold or cultivated in the state. The popular, non-native, ornamental shrub forms dense, prickly thickets that crowd out plants and disrupt native ecosystems.

It is also thought to harbor black-legged ticks that spread lyme disease. The ban on sale and cultivation took effect Oct. 8. Enforcement of the ban will be phased in over two years to allow time for nurseries to eliminate it from their stock, find non-harmful alternatives and develop seedless, sterile varieties that pose less threat to the environment and agriculture.

Landscape and nursery businesses will receive notices of the timeline, procedures and exemption process for sterile varieties. Property owners should consider eliminating the shrubs on their land.

Japanese barberry was originally brought to the U.S. from Japan and eastern Asia in the 1800s to be planted as an ornamental. It is widely used as a landscape shrub because of its fall coloring and resistance to deer. It has garnered attention in the past several years as a prolific invader that can easily spread into woodlands, pastures, fields and natural areas.

The timeline for the two-year rollout of the ban is as follows:

November 2021 — Nursery and landscape businesses will receive notice from the department, advising them to immediately begin adjusting propagation, ordering and planting of Japanese barberry to decrease inventory.

Fall 2022 — The department will issue letters of warning to any plant merchant still selling Japanese barberry, providing a date in Fall 2023 after which remaining inventory will be subject to a destruction order.

Fall 2023 — The department will issue stop sale and destruction orders to plant merchants selling or distributing Japanese barberry.

Merchants with questions should contact ra-plant@pa.gov.

Effective Oct. 8, the department added two other plants to the noxious weed list: garlic mustard, Alliaria petiolata, and Japanese stiltgrass, Microstegium vimineum. These plants are generally not sold in nurseries but are invasive and common in Pennsylvania. Landowners with these plants on their property are encouraged to remove them.

Find more information about noxious, controlled and poisonous plants in Pennsylvania at agriculture.pa.gov. For comprehensive information about controlling invasive species in Pennsylvania, visit the Governor’s Invasive Species Council.