A team of researchers has received a grant to begin a multiyear project to first identify and then begin eradicating invasive plants in the upper Saco River and its floodplain.

“Most of the work has been done in lakes with aquatic invasives,” the Nature Conservancy’s Stefan Jackson said Monday. He’s the organization’s Saco River project director. “They are more damaging, and are a greater threat immediately, but a lot of the resources have not been focused on river systems.”

And although rivers move more swiftly, decreasing but not eliminating the possibility of a rapid takeover by a foreign plant, the bogs, ponds, wetlands, tributary brooks and land around the river are vulnerable to being overcome by an aggressive species.

The $25,193 grant, which is funded by instant lottery sales tickets in Maine, is administered by the Maine Outdoor Heritage Fund. For the past 10 years, the fund, which means to conserve wildlife and open space in the state, has given out between $700,000 and $1 million annually, depending on the number of $1 lottery tickets sold. The total awarded during the last decade has been $12 million to more than 500 projects, according to Dick Anderson, chairman of the board.

Anderson said grants are given out twice a year to between 30 and 50 organizations. The criteria for funding recipients generally includes whether it’s a good research project, a good public policy issue, or if it benefits a wide geographic range, Anderson said.

Other projects funded this year include the stabilization of eroded areas along the Appalachian Trail, the purchase of 3,688 forest acres in Grafton Township, and supporting a University of Maine research project that will study the taxonomic status of the Clayton’s Copper butterfly, which is on the state’s endangered species list.

Mapping invasive plant species along a 35-mile stretch of the Saco River is projected to take three years, Jackson said. The roughly $25,000 grant will be matched in-kind by another $28,000, he said.

The Nature Conservancy is working with the Oxford County Soil and Water Conservation District, the Saco River Recreational Council and the Saco River Corridor Commission.

The entire area to be mapped – from the New Hampshire border to Hiram – consists of 20,000 acres of floodplains, 35 miles of river, and an old river route, all in all about 50 square miles, Jackson said.

The surveyors will be looking for the top 10 most pernicious terrestrial plants that can quickly spread and alter the ecosystem. But the mappers might find other unknown species, too.

“This is only meant to be the first phase. The first step is to know what we’re dealing with, the second is eradication and management, and the third is the follow up of monitoring and reacting in a long-term stewardship plan,” Jackson said.

According to the grant application submitted for the project, invasive plant control and reduced agricultural production caused by the invasive plants costs $20 billion a year nationwide. “Maine has so far been spared the full brunt of this invasion. However, anecdotal evidence is mounting that invasive plants have gained a foothold and are spreading in the upper Saco River watershed. It is essential at this time to gather baseline data from which future incursions of invasive plants and the effectiveness of control efforts can be measured,” the application states.