Japanese barberry, a tick-harboring shrub, could be banned in Pennsylvania at the first meeting of the new Controlled Plant and Noxious Weeds Committee in the Pennsylvania Department of Agriculture later this month.
The plant is widely popular in the state's nursery and landscape industry. It's cheap, attractive, hardy and disease resistant. It can be grown as a dense, tall hedge or specimen planting.
It's also a fast-spreading, highly invasive species that crowds out native plants. According to the Center for Invasive Species and Ecosystems Health, Japanese barberry "invades a variety of habitats from shaded woodlands to open fields and wetlands. Berberis thunbergii is rapidly spread by birds that eat the berries thus dispersing the seeds."
And, it's a frighteningly great home for Lyme disease-carrying ticks. Researchers at the University of Connecticut discovered that tick numbers are much higher in areas with Japanese barberry.
"When we measure the presence of ticks carrying the Lyme spirochete (Borrelia burgdorferi) we find 120 infected ticks where Barberry is not contained, 40 ticks per acre where Barberry is contained, and only 10 infected ticks where there is no Barberry" said adjunct professor Scott Williams.
The plant already appears on the Pennsylvania Department of Conservation and Natural Resources list of invasive species, which the agency defines as "those species that are not native to the state, grow aggressively, and spread and displace native vegetation."
Pennsylvania's noxious weed list represents a step beyond invasive to "a plant part or plant in any stage of development that is determined to be injurious to crops, livestock, agricultural land or other property, including forest land and bodies of water."
While the Department of Agriculture has maintained a noxious weeds list for decades, the Controlled Plant and Noxious Weeds Committee was created in October 2017, part of the Controlled Plants and Noxious Weeds Act.
The meeting later this month will be the first for the committee established specifically to designate noxious weeds and controlled plants.
The committee is comprised of the secretaries of the departments of Agriculture, Conservation and Natural Resources, Environmental Protection and Transportation; the executive directors of the Pennsylvania Fish and Boat Commission and the Pennsylvania Game Commission; the chairmen and minority chairmen of the Agriculture and Rural Affairs Committee in the state Senate and House of Representatives; and 3 persons appointed by the agriculture secretary: one a member of a statewide general farm organization; one representing the ornamental, turf and horticultural industry; and one from an institution of higher education.
Japanese barberry's invasive qualities and status as a home for ticks aside, the committee must consider how injurious it is to crops, livestock, agricultural land or other property, as well as the economic impact of adding it to the noxious weeds list, according to Shannon Powers, deputy communications director with the Department of Agriculture.
She noted that it's "a top seller for nurseries. It's very attractive, and resistant to disease. It's been a big seller."
Japanese barberry is native to Asia. It was introduced as an ornamental plant into the U.S. in 1864 and continues to be planted widely.
More about ticks and invasive species in Pennsylvania:
- With 25 species of ticks lurking in Pennsylvania, which ones are the most dangerous?
- Ticks and Lyme disease: The problem 'no one's really doing anything about'
- Tick 411: How to prevent bites, remove ticks and know if you have Lyme disease
- Invasive plants are swallowing Pennsylvania