Pa. bans sales of Ravenna grass and 2 species of buckthorn trees

While spring gardening might not be foremost on residents’ minds during a snowstorm, the state announced Friday it will ban plant sales of certain pampas grasses and two varieties of buckthorn.

The state Department of Agriculture added three species to the state list of noxious weeds, which are non-native invasive plants that cannot be sold or cultivated.

The new plants added to the list are Ravenna grass (Tripidium ravennae) also known as hardy pampas grass, glossy buckthorn (Frangula alnus), and common buckthorn (Rhamnus cathartica).

In the southwestern part of the state, all three banned species are present in the natural landscape but are not prevalent in natural areas, said Amy Jewitt, invasive species coordinator for the Western Pennsylvania Conservancy.

“This ban is a major win,” she said. “These invasive plants will no longer be entering the environment and won’t be spread in natural areas.”

However, because the plants, except the common buckthorn, are commercially sold, they are found in residents’ yards.

Ravenna grass is a 6-foot-tall, perennial, ornamental grass commonly sold in nurseries. Its seedy plumes choke out native plants and spread easily.

Not all types of pampas grass are banned, said Shannon Powers, an agriculture department spokeswoman.

Penn State Extension Master Gardener Louisa Fordyce has some distant relatives of the plant in her yard.

“I have zebra grass, which enlarges, but it’s not spreading anywhere,” she said. “I also have Karl Foerster perennial grass; that just stays in a clump. But the true pampas grass does have very fertile seeds, and it can be spread easily by wind and by birds, which is where the problem can come from.”

Related:

• Vomit-fumed 'Bradford' pear tree lands on Pa. noxious weeds list, with sales to be banned
• Pennsylvania will fully ban sale of Japanese barberry by fall 2023

• Editorial: Invasive species are environmental threat everyone can fight
• Goats help rid Frick Park of invasive plants
• From 2018: Invasive plants: Southwestern Pennsylvania's most wanted list

Glossy buckthorn is a small tree or shrub that produces berries eaten by birds, which spread the seeds. This plant “aggressively spreads in wetlands,” according to the Department of Agriculture.

The glossy buckthorn has a commercially available cultivar named “rhamnus fine line.” The department has an exemption procedure for breeders who own the rights to varieties that have proved sterile. Enforcement of the ban on sales begins in 2023.

Common buckthorn is a non-native invasive tree that is not sold commercially. This tree forms dense thickets, choking out native ecosystems, according to the department.

Local gardeners should consider removing these plants if they haven’t already, given their aggressive growth, Powers said.

Fordyce said drivers on the Route 66 Bypass will be able to see part of the rationale behind the banning of species, such as a particular variety of Callery pear (Pyrus calleryana), later this year.

“If you travel the 66 bypass from Delmont to Greensburg in the spring, look at the white, blooming trees on the hillsides. Those are Callery or Bradford pears, and it is doubtful that they were planted in those areas,” she said.

Mary Ann Thomas is a Tribune-Review staff writer. You can contact Mary Ann at 724-226-4691, mthomas@triblive.com or via Twitter @MaThomas_Trib. Patrick Varine is a Tribune-Review staff writer. You can contact Patrick at 724-850-2862, pvarine@triblive.com or via Twitter @MurrysvilleStar.