Like Closing the Barn Door After the Horse Gets Out . . .

Yellow Flag Iris

Maryland bans sale of 3 ornamental invasive plants, more to come

Maryland is stepping up the fight against ecosystem-altering nonnative plants by banning the sale of three aggressively spreading ornamentals and requiring that warnings be posted next to retail displays of five others sold in garden stores and nurseries.

The sales bans for shining cranesbill, yellow flag iris and fig buttercup don’t take effect until next year, but warnings for the other species will be required starting July 12. The Maryland Department of Agriculture mandates are the agency’s first restrictions on the sale of ornamental plants.

Shining Cranesbill

While I haven't seen any of these for sale, the Yellow Flag Iris, for at least one, are well established around here already. I know of several small patches of them in various places, and they don't seem to be a particularly vicious invader. They seem to like sunnier habitats than the native Blue Flag Iris, and (based on the specimens in my pond) slightly larger and more robust to lousy treatment.

The MDA action, long sought by people battling nonnative invasive terrestrial plants, was hailed by some as a dramatic first step amid a wave of vegetative change is overtaking many urban, suburban and even rural areas. Hundreds of volunteers and state and local government staff have been trying to stop the spread of invasive plants by pulling them out of the ground and replacing them with native plants, only to see the invasives roar back.

“This is unprecedented in Maryland, and a very uncommon step for any state to take,” said Carol Bergmann, a forest biologist with the Maryland-National Capital Parks and Planning Commission (M-NCPPC), the parks agency shared by Montgomery and Prince George’s counties. She predicted that other invasive plants will be subject to sales restrictions over time.

Fig Buttercup

One reason that invasives do so well, is that that they are pre-adapted to the changed conditions that civilization and agriculture have imposed on the environment. In short, they're simply more fit than the natives.

The MDA action was recommended by the Maryland Invasive Plant Advisory Committee, a panel established by state law in 2011, when lawmakers directed the MDA to regulate invasive plants harming non-agricultural areas.

But the MDA rule is too little, too late, said Laurie Taylor-Mitchell, the lead “weed warrior” in Baltimore County’s Cromwell Valley Park.

Taylor-Mitchell said one of the plants to be banned, fig buttercup, also known as lesser celandine, already blankets 12 acres of the park. Like many other invasives there, she said, it has overwhelmed and replaced native plants and comes back even if pulled out. Making matters worse, she added, deer will eat any native plants that appear, but not lesser celandine.

“This a terrible problem,” Taylor-Mitchell said. “The house has been on fire for years—and now they’re deciding to ban sales of the plant?”