Boats heading through the Songo River lock will be inspected for plant fragments as part of the effort to stop the spread of milfoil, three state agencies announced today.

Officials from the Maine Department of Environmental Protection, the Maine Department of Conservation and the Maine Department of Inland Fisheries and Wildlife said they hope the inspections will halt the upstream migration of milfoil, an invasive plant that can grow into dense mats at the surface of the water, cutting off oxygen from deeper water.

The inspections will start this week, using both volunteers and paid inspectors. Boats traveling upstream from the Lower Songo River will be inspected as they go through the lock, possibly causing some delays for boaters on the river, which connects Sebago Lake to Brandy Pond and Long Lake.

Any plant fragments that are found will be removed and disposed of, officials said.

Officials said they hope the inspections will stop the spread of milfoil without having to close the lock.