Called insidious, aggressive, and opportunistic, phragmites is the Rasputin of plants with a root system akin to the Boston mob, and in Marion and Mattapoisett the plant is legion.

The invasive reed is taking over many marshes and wetland areas on the South Coast and it isn’t easily conquered. But conservationists say it can be defeated with a good plan and plenty of perseverance.

And if you’re looking to get rid of them, restoration ecologist Sara Quintal says “’tis the season.”

The tall, hearty plants with the feathery tips have almost no predators in the U.S., said Mattapoisett Land Trust President Gary Johnson, and their root systems are hard to beat.

“It creates a massive root structure that becomes impenetrable to native species,” Johnson said.

In addition to killing beach views, the matted roots push out cattails and other native plant life and can eventually change the elevation of marshes.

They can also impact wildlife.

“It’s not that nothing will use phragmites. . .but there are definitely a lot less native animals that will use it compared to a native marsh,” explained Quintal, who works for the Buzzards Bay Coalition.

Quintal said the reeds come from Asia, South America, and Australia, but how they arrived on local shores is uncertain.

“One phragmites expert said it started with the major hurricanes in the 1950s. Some may have come in with nursery plants or a plant someone might have brought from visiting another country,” said Quintal.

Getting to the root of the problem

Most experts recommend an aggressive three-year plan to knock back the reeds, using the herbicide Rodeo.

“It’s not something where you can just whack down a bunch of phragmites,” said Mattapoisett Conservation Agent Elizabeth Leidhold. “It would be part of a whole maintenance plan, pulled together with the help of an engineer.”

The first year involves applying the herbicide to each stalk during late summer or early fall, followed a few weeks later by mowing down the stalks. Quintal said the second and third years involve smaller follow-up treatments as well as “hand wicking” – pulling the stalks out by hand.

The treatment, when done with a qualified expert, can result in a 99 percent eradication of the plants.

But Marion and Mattapoisett do require a notice of intent and a detailed plan before granting permission to remove the reeds.

The purpose of phragmites removal isn’t to add acreage to your lawn, emphasized Leidhold. “It’s a wetland and needs to stay a wetland,” she said. “Removing them without a permit is an enforcement situation.”

The Mattapoisett Conservation Commission recently granted a property owner permission to begin a phragmites removal plan.

In Marion, Conservation Commission Vice Chair Norm Hills said the town is working on removing phragmites at Sprague’s Cove, built in 1995.

“It was never really maintained and, as a result, it got overrun,” said Hill. “We’re trying to get it back to where it was so we can maintain it.”

So far, contractors have performed two treatments on the cove, and the commission encouraged adjacent property owners to remove their phragmites as well.

Maintaining the madness

Although there are proven methods for keeping phragmites at bay, it’s not as simple as a good plan. Reed removal is expensive.

Johnson said the trust has tried to remove the plants on some of its smaller properties but others require more manpower and money than the small nonprofit can afford.

“We’ve got massive infestations on some of the parcels,” he said. “We don’t know what we would ever do with it.”

Secondly, if there is no treatment on nearby properties, the problem can return.

“You’ve got to be committed to doing it, and it takes multiple years. If your neighbor doesn’t do it, the stuff will creep back in,” said Hill.

Lucky for the Buzzards Bay Coalition’s Mattapoisett River Reserve property on Acushnet Road, there are only a few phragmites so far.

“We’re attacking them by hand, mostly with volunteers, trying to knock them back a few times during the growing season,” said Quintal. With much of the land retired bogs, she said, “They could take over that whole property if we didn’t do anything.”

But the villainous reeds are not completely without value.

“It may not be the end of the world,” said Leidhold. “[Phragmites] does remarkably well in containing hazardous materials. It can actually pick up heavy metals and pollutants.”