Maine Lakefront Property Owners Appreciate Songo River Success Story

posted Jan 11, 2016, 4:56 AM by Joseph Bickard
The year was 2004 and the Songo River was so infested with the aquatic

invasive variable-leaf milfoil (Myriophyllum heterophyllum) that people

thought it was crazy for Lakes Environmental Association to take on the task

of eradicating it. If you know LEA’s Executive Director Peter Lowell,

however, you know he welcomes a challenge.

Milfoil covered sixty percent of the river. In some coves and straight-aways

there were enormous infestations. Lowell describes it as looking like guts in

the water.

Variable-leaf milfoil has a thick, reddish stem with whorls of finely-divided

leaves. The roots are thin and fragile—think angel hair pasta.

This milfoil prefers to grow in relatively calm and shallow (less than 20 feet)

waters. Typically, it grows straight up, but in shallower water the stem turns

and the plant begins to grow horizontally, thus creating a thick mat.

Its main form of reproduction is by fragmentation. Broken shoots are carried

downstream by water currents, boats and waterfowl. It only takes a small

piece of the plant to begin a new population.

Milfoil can negatively impact native species, recreation and even property

values around infected waterbodies.

Traveling along the river this past summer with an LEA employee, I learned

that there’s hardly a plant visible.

Our tour included visiting sites where the infestation had been heaviest, such

as behind the sandbar at Sebago Lake State Park, by the rope swing along the

river’s edge and at the Songo Lock basin.

The milfoil crew consists of six to eight strapping young men. This is a skill-
based job—learning to identify the plant, lay the barriers, scuba dive, etc. The

learning curve is huge, so he appreciates that the team members return year

after year.

Crew leader Christian Oren has been with the team for nine years, his

brother Tyler for eight. Derrek Douglass and Thomas Chagrasulis are four-

year members. Sullivan Tidd and Lucien Sulloway joined the crew two years


Their work base is the SS Libra, a pontoon boat purchased with grant money

from the Libra Foundation. The boat houses a Diver Assisted Suction


The DASH provides an efficient method to remove milfoil from the water. It

has a suction hose that divers carry into large infestations. While underwater,

they harvest milfoil by the roots and feed the material into the hose.

Aboard the Libra, roots, stems and leaves are then processed in its sluiceway,

which bags the plant material. This harvesting technique allows divers to

remove large quantities while maintaining underwater visibility.

For smaller infestations, they remove plants by hand, placing the plant

material in dive bags. Once harvested, the milfoil gets composted away from

the water.

In some infested areas, the crew also uses benthic barriers to manage the

invasive plant. To do this, they need permits from Maine’s Department of

Environmental Protection.

Over the years, they tried a variety of materials including large tarps, shrink

wrap and biodegradable burlap, which they laid on the sediment and secured

with stakes.

The benthic mats restrict sunlight from reaching the bottom; the absence of

light on the substrate halts the growth of the plants—both native and

invasive. This is a chemical-free form of treating the plants and is reusable.

The rotting vegetation produces gases and causes the mats to bubble up.

Periodically, the crew deflates the bubbles to keep the barriers from

becoming a problem for swimmers and boat props.

The barriers are removed after they’ve done their job of smothering milfoil,

thus allowing native plants to regrow from the seedbank in the sediment.

On our journey, we stop to chat with the crew. Douglass of Bridgton, recalls

his first day on the job, “It was like a sea of milfoil. There were giant patches.

It was really thick and you couldn’t swim.”

One of the worst sections was at the shallow point by the rope swing. Boaters

using the swing ignored the milfoil warning signs, thus driving right into the

patch and breaking the plants into fragments.

At the state boat launch by Sebago Lake State Park there was another solid

band of milfoil four years ago. Now there is little to no evidence of it.

In 2014, they worked on the channel that leads from the boat launch to

Sebago Lake. This summer, they discovered some sparse re-growth, all easily

removed by hand. While the crew continues to patrol, they’ve found no new


Throughout the 2015 season, they surveyed areas where they had previously

removed plants. The program has been highly successful and they often find

either no invasive plants or only a few growing where they were once

incredibly dense.

Oren says, “We see a lot more native plants where there was milfoil. It’s now

the correct habitat for them and huge schools of fish swim through.”

It used to be that they harvested thirty to fifty bags worth of milfoil each day.

And every two days, they made a trip to the compost pile. This year, their

combined finds didn’t fill one bag a day and they waited two weeks before

dumping the weeds on the pile.

Lowell is extremely impressed with the work that has been completed and

recognizes that all the money invested into this program has paid off. He

never thought it would be as clean as it is today. “We know now that we can

control it,” he says.

John McPhedran, Maine DEP’s Invasive unit leader, is equally impressed.

He encouraged Lowell to remove the milfoil signs along the river. “Given

LEA’s phenomenal success of controlling the milfoil in this river corridor –

there are no longer dense patches of variable milfoil along the river – Peter

agrees with removal of the milfoil-related signs.” He also suggested that the

yellow milfoil buoys be removed.

The hope is that for 2016, the river won’t need the crew as much. They’ll still

continue to check it, but in a diminished capacity.

Kudos to LEA and the crew for the success story on the Songo River and

Brandy Pond. But, we all need to remember that fragments can stow away in

boats, trailers and fishing tackle where they could potentially spread to

unaffected bodies of water. Yes, it can be controlled, but the cost is high. It’s

quite easy, however, to check your boat before and after you float to make

sure you aren’t helping spread this and other aquatic invasive plants from

one waterbody to another.

by Leigh Macmillen Hayes