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Report to CPC_2022-08-25_Contract_FINAL.pdfFINAL REPORT TO THE COMMUNITY PRESERVATION COMMITTEE FROM THE BROAD BROOK COALITION AUGUST 2022 Goals: Broad Brook Coalition continued its efforts to control or eradicate several species of invasive plants in the Fitzgerald Lake Conservation Area (FLCA) frrom 2019-2021 with funding awarded by the Community Preservation Committee. The long-range goal of this work is to preserve the native habitat of the FLCA by controlling the proliferation of a variety of invasive plants as well as to discourage their resurgence in the future through periodic monitoring. As in the past, the primary target species were glossy buckthorn (Rhamnus frangula) in Cooke's Pasture and its periphery, black swallow-wort (Cynanchum louiseae) in Cooke's Pasture, and spotted and brown knapweeds (Centaurea maculosa and Centaurea jacea) in Cooke's Pasture and on the Fitzgerald Lake dam. Small amounts of several other invasive plant species were also targeted. General Approach: Cooke's Pasture consists of approximatey seven acres and is maintained as open shrubland by periodic mowing. Owing to work performed over the past several years, we no longer have the dense concentrations of invasive plants in the pasture and adjoining areas that we faced fifteen years ago and estimate that the populations of the targeted plants has been reduced by over 95% compared to their prevalence in 2008--2009 when control efforts were initiated. Rather, they are now dispersed, requiring the selective targeting of individual invasive plants in a background of native plants. Land Stewardship, Inc. (LSI)), which has carried out this work, has proven to be very adept at limiting herbicide treatment to target plants without causing collateral damage to surrounding grasses, flowers and native shrubs. Access to Cooke's Pasture was improved in 2020 by the removal of several large rocks on the entrance pathway by RCW Landscape Construction Black Swallowwort in Cooke's Pasture. Black Swallowwort is an invasive vine that can compete with native vegetation, replacing grasses, goldenrod and milkweed by monotypic mats that negatively impact insects and animals such as turtles and birds that depend upon a healthy grassland or shrubland habitat. A small patch of black swallowwort was discovered in the central lobe of Cooke's Pasture in 2012. Sporadic herbicide treatment failed to prevent this plant from going to seed and the infestation expanded to roughly one-quarter of an acre. A systematic effort to eradicate black swallowwort, initiated in 2016, has reduced the size of the infestation to less than one-tenth of an acre by treatment of individual plants with herbicide. The small number of plants found in 2019 were spot-sprayed with Vastlan (a triclopyr derivative) and Escort XP (metsulfuron methyl). In 2020, there was no swallowwort in the pasture, though a dozen plants were discovered in the adjacent woods and spot-sprayed with the Vastlan-Escort mixture. In 2021, the few remaining plants were treated with herbicide. We will continue to monitor this area in the future to make sure that no swallowwort persists. Knapweed in Cooke's Pasture and on the Fitzgerald Lake Dam. LSI crews targeted spotted and brown knapweeds in Cooke's Pasture and on the dam each summer of the contract. At the same time, they also treated smaller amounts of other invasive plants, including bittersweet, multiflora rose and exotic honeysuckle. Knapweed plants were treated with a low-volume foliar spray of Vastlan and Streamline (sulfonyl urea). In general, knapweed seems to be under good control: their abundance was low throughout and found mostly along field and trail edges. This is good news as, If left unchecked, knapweeds can overtake grassy fields and maintain their predominance through the release of products that adversely affect the growth of native plants. We will endeavor to keep these plants under satisfactory control in the future through close monitoring and spot herbicide treatment. Buckthorn in Cooke's Pasture and the Forested Perimeter. Roughly eight years ago, it became evident that mature glossy buckthorn trees growing in the ~9-acre forested buffer zone between Cooke's Pasture and the Broad Brook marsh provide an abundant source of seeds that can spread and give rise to new buckthorn growth in the pasture. Some of these trees were treated with herbicide in 2011 and 2013, but coverage was not complete and a number of large buckthorns persisted in the periphery. In March 2016, buckthorns in the buffer zone were systematically cut in preparation for subsequent herbicide treatment. LSI crews treated buckthorns in Cooke's Pasture and its forested buffer zone each summer with either Rodeo, Vastlan, Streamline or Garlon 3A using a targeted, low-volume foliar spray. In 2020, the crew returned twice to complete the suppression of plants on the forest periphery as well as in the pasture. A significant number of small buckthorns were also noted on the adjacent forest floor at that time. In 2021, a crew from LSI came out in December to remove large buckthorns remaining on the forest edge with chain saws and brush saws, and the stumps were treated with Rodeo using the cut-stem approach. At that time, the crew commented that there were still large buckthorns between the southern pasture edge and the Broad Brook marsh. It is evident that buckthorn infestation in this area will persist for some time and will need more effort to eradicate. Other Efforts to Control Invasive Plants in the FLCA. In each of the past three years, volunteer crews removed garlic mustard and multiflora rose by hand at the North Farms Road entrance to the FLCA, cut back multiflora rose, bittersweet, winged euonymous, and other invasive plants along Boggy Meadow Road, and pulled large amounts of water chestnut from Fitzgerald Lake. At the same time, follow-up herbicide treatment of Japanese knotweed on Marian Street and of Phargmites in the Broad Brook marsh were carried out by O'Gara Landcare with funding from the BBC. August 25, 2022 Robert A. Zimmermann President Broad Brook Coalition BUDGET SUMMARY Expenditures in 2019: Budgeted Expended Landscape Stewardship, Inc. Black swallowwort control in $ 250 $ 250 pasture Buckthorn control in pasture 1,600 1,600 and forest perimeter Knapweed control in pasture 600 600 and on dam Subtotal: 2,450 Expenditures in 2020: Landscape Stewardship, Inc. Black swallowwort control in 250 250 pasture Buckthorn and knapweed control in 2,000 2,000 pasture, forest perimeter and dam Subtotal: 2,250 Expenditures in 2021: Landscape Stewardship, Inc. Black swallowwort control in 250 250 pasture Buckthorn and knapweed control in 2,000 2,000 pasture, forest perimeter and dam Subtotal: 2,250 Total: $ 6,950 $ 6,950