Japanese barberry, or Berberis thunbergii, an invasive but popular landscaping shrub due to its red color and deer resistance, will be illegal to sell or cultivate in Pennsylvania by Fall 2023. The PA Department of Agriculture added Japanese barberry to a list of noxious weeds — plants that cannot be legally sold or cultivated in the state—last month. The non-native, ornamental shrub forms dense, prickly thickets and has increasingly garnered attention in the past several years as a prolific invader that can easily spread into woodlands, pastures, fields and natural areas, crowding out plants and disrupting native ecosystems. It is also thought to harbor black-legged ticks that spread lyme disease. The ban on sale and cultivation took effect October 8, 2021. Pennsylvania now joins other northeastern states, such as New York, Maryland, and others, that ban or restrict the sale of Japanese barberry. In Maryland, for instance, the Department of Agriculture (MDA) has named it a Tier 2 invasive plant. This classification means retail stores must display a sign indicating it’s an invasive plant and landscapers may not supply it unless they provide their client with a list of Tier 2 invasive plants. Enforcement of the ban in PA 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 ...