DCR is aiming for a fall start of a pilot program to test various methods for restoring the banks of the Charles River Basin and reducing the amount of invasive trees and other plants along the banks that it says crowd out native species and reduce the vistas of the scenic waterway.
In eight relatively small plots - the largest 20 by 50 feet - the department plans to test methods of bank restoration and plant control to determine the best way to repair banks that have been heavily eroded, sometime by the wakes of all those motorboats that ply the basin control such invasive species as ailanthus trees and purple loosestrife.
Sometimes, the two goals will go together - a test plot on the west side of the Esplanade dock will involve "revegetation with low-lying native shrubs and herbaceous perennials recommended to prevent degradation of the bank."
The Boston Conservation Commission discusses the proposal at a meeting that begins at 6 p.m. on Wednesday.
In a filing with the Commission, DCR discusses the bank problem along the basin:
The Lower Charles River shoreline along Boston, Cambridge, Newton, and Watertown offer mature shade trees that make a significant contribution to the urban forest. Volunteer plants have established themselves along most of the shoreline and include shrubby growth along the river banks; however, erosive flows and wave action from the river's active boating community have severely undercut parts of the shore. Some trees and shrubs lean toward the water; others have lost the battle with gravity and have toppled in. At the same time, invasive plants have knit themselves into the plant community. Purple loosestrife, Japanese knotweed, multiflora rose, and others expand their range from season to season, squeezing out native plants. Additionally, several non-invasive, but visually obstructive, species such as pokeweed and false indigo bush overgrow and fill vistas where maintenance staff struggle to keep views open for both daily passive use as well as highly anticipated annual events such as the Head of the Charles Regatta.
Complete DCR filing (69M PDF, includes copy of 2018 report on Charles River Basin vegetation).