ACADIA NATIONAL PARK – The purple, blue and pink lupine that brighten the state each June are as much a part of the coastal Maine landscape as lighthouses, rocky cliffs and shore dinners.

Lupine that take root within the boundaries of Acadia National Park, however, might not be welcome much longer.

“We’re dealing with a showy, beautiful plant that’s an icon of the state of Maine, but it doesn’t really belong here,” David Manski, chief of resource management at the park, said Friday. “It has its place and that’s not Acadia.”

Lupine, though as familiar here as pine trees and pounding surf, is a non-native species. It was introduced years ago as a landscaping plant and has never left. There was a strain of lupine that was native to the state of Maine, but that has become extinct, Manski said.

Lupine are one of more than 200 non-native plants that live on the Mount Desert Island, almost a quarter of the total number of plant species.

Some non-native plants, like apple trees, do not compete with native plant species. Others, like purple loosestrife, the aggressive wetland plant, do.

As for the lupine, the verdict is still out.

Park botanists began work two weeks ago to cut the plants at a spot where Ledgelawn Avenue meets the Park Loop Road.

Workers used “weed-whippers” to contain the plants at that location, Manski said. Surprised reactions from park visitors and island residents led the park to curtail its containment program for the time being.

“There were very strong feelings,” Manski said. “We certainly were caught off guard. … Obviously, people love lupines, and with good reason, but in a national park, lupines are not part of the natural landscape.”

On Friday afternoon, a lone hiker walked in the rain beside the patch of remaining lupine. The purple blossoms glistened with droplets of water, their regal heads hanging heavy with the weight of rain. Brown, limp lupine stalks rotted on the ground, a visual reminder of the park’s first containment efforts.

Park staff have put down their weed-whippers and whackers and picked up scientific journals in order to research whether or not the lupine will threaten the native ecosystem.

“We want to find out what kind of ecological effects they might have,” Manski said. “I know they spread and they spread particularly along road shoulders and areas where there’s open sun.”

Ann Judd, a member of the Garden Club of Mount Desert, said Friday that more research on the flower would be welcomed.

“I would like to hear all the information on the case to eradicate lupine,” she said. “We all love the beautiful blue color and the stands we see along the road and the hillside.”

Judd said that she grows lupine in her own garden, in part because butterflies flock to the blossoms.

In a state that even has a festival dedicated to the popular flowers, it is hard for many to imagine that the familiar lupine is now controversial.

“I think they’re beautiful,” Anne Beerits, an organizer of this weekend’s Deer Isle-Stonington Lupine Festival, said Friday. “And they have a kind of a Maine mystique. … They’re sort of an harbinger of early summer, and I think for people that live in seasonal communities like this, everyone really welcomes any harbinger of warm weather and spring.”