PORTLAND (AP) – A fast-spreading shrub has taken over more than a third of Monhegan Island’s forest underbrush, but residents are starting to fight back.

For a couple of hours each Wednesday, volunteers work to remove Japanese barberry by hand. It’s an uphill task, given the plant’s advantages.

First brought to North America in the late 19th century, Japanese barberry spreads quickly, and if it gets out of control it can crowd out native species and change the character of a forest.

The shrub’s leaves turn red and orange in the fall, making it popular among gardeners and homeowners. Birds love to eat its red berries, and deer also contribute to the plant’s spread.

“Deer don’t like to eat it,” said Don Cameron, of the Maine Department of Conservation. “Therefore they eat everything else and they leave the barberry behind. So that gives the barberry another advantage, as if it needed one.”

Residents of Monhegan, which lies about nine miles off Maine’s midcoast, have known about barberry’s presence for some time.

But it wasn’t until recently that they learned how fast and how far the thorny plant had spread. Now they are considering various plans to get it under control.

More than 50 people came to the island schoolhouse last week to hear Bill Livingston, a professor at the University of Maine, talk about the impenetrable thickets of barberry he found during a survey of the island’s forests.

Livingston said he could not get into parts of the forest because the barberry was so thick. In some places, the shrub grew six feet high.

“The thorns are so effective that we couldn’t get in and do our sampling there,” Livingston said. “It was just inaccessible.”

The shrub has been found in 10 Maine counties and 28 towns, but the state has not begun phasing out its horticultural use, as some states have, Cameron said.

The Wells National Estuarine Research Reserve has had a barberry problem for years. It has become the dominant undergrowth in many parts of the reserve, and officials are now taking an aggressive approach with regular mowing and occasional burning.

“To use a botanical metaphor, if you discover Japanese barberry, nip the problem in the bud and get rid of it,” said Paul Dest, the reserve’s manager.

On Monhegan, where barberry was found on 150 of the 360 forested acres, volunteers have so far concentrated on removing the plant by hand.

Since the island is isolated from the mainland, Livingston said, it would make a good area to study how to get rid of barberry.

“We’re going to see if we can’t get some funding together to use this (island) as a model project for how to deal with an invasive like this,” he said. “Are we really able to reclaim the forest back from this invasive where it’s taken over?”

AP-ES-08-19-03 0216EDT

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