Loading...
2016 ReportREPORT TO THE COMMUNITY PRESERVATION COMMITTEE FROM THE BROAD BROOK COALITION (CONTRACT 331-16) DECEMBER 2016 Goals: The primary goals for the first year of this contract were to continue suppression of several invasive plants in the Fitzgerald Lake Conservation Area (FLCA): 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. General Approach: Owing to work performed over the past several years, we no longer have the dense concentrations of invasive plants in Cooke's Pasture and adjoining areas that we noted in 2008-2009. Rather, they are now dispersed, requiring the selective targeting of individual invasive plants in a background of native plants. Land Stewardship, Inc. (LSI, formerly Polatin Ecological Services, LLC), which has carried out most of 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. Glossy Buckthorn in Cooke's Pasture and Its Forested Perimeter. Cooke's Pasture consists of approximatey seven acres and is maintained as open shrubland by periodic mowing. Roughly five 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 numer of small as well as large buckthorn plants persisted in the periphery. In March 2016, buckthorns in the buffer zone were systematically cut in preparation for subsequent herbicide treatment. At the same time, buckthorns within the planted shrub islands in the pasture were subjected to targeted cut-stem herbicide treatment. This work was carried out under CPA contract 250-13. Under the present contract, LSI returned for two days in the second week of August 2016, to treat re-sprouted buckthorn in the Cooke's Pasture buffer zone as well as newly sprouted buckthorn in the open fields. The plants were treated with a targeted, low-volume foliar spray containing the herbicides Garlon 3A, Escort XP and Milestone. In both areas, spotted and brown knapweeds, as well as small amounts of other invasive plants, including autumn olive, bittersweet and exotic honeysuckle were also targeted. A crew from LSI then returned in late August to treat any plants missed in the earlier herbicide application. At the same time, knapweed on the Fitzgerald Lake dam was also targeted. Visual inspection in the fall indicated that most of the buckthorn and knapweed in the pasture and buffer zone and on the dam had been killed. Black Swallow-wort in Cooke's Pasture. Black Swallow-wort is an invasive vine that can compete with native vegetation, replacing grasses, goldenrod and milkweed by monotypic mats and negatively impacting insects and animals such as turtles and birds that depend upon a healthy grassland or shrubland habitat. A small patch of black swallow-wort was discovered in the central lobe of Cooke's Pasture in 2012. Sporadic herbicide treatment has failed to prevent this plant from going to seed and the infestation has expanded to roughly one-quarter of an acre over the past four years. As part of a systematic effort to eradicate black swallow-wort, individual plants were treated with Garlon 3A by LSI in June and again in August. We will not be able to judge the efficiency with which seed production was curtailed until summer 2016. Plans for 2017 1. Foliar herbicide application will be used to control Black Swallow-wort in Cooke's Pasture in June and August. 2. In July, a crew from LSI will use low-volume backpack sprayers to target buckthorn, knapweed and other invasive plants in Cooke's Pasture and on the Fitzgerald lake dam. The crew will return in August for a follow-up treatment. Expenditures in 2016: Landscape Stewardship, Inc. Budgeted Expended Buckthorn control in buffer zone, $ 2,500 $ 2,500 Black Swallow-wort in pasture Buckthorn, knapweed control in pasture 1,500 1,500 Follow-up Treatments 2,100 600 Total $ 6,100 $ 4,600 2016-2018 Budget Summary: Initial Award $12,800 Expended, 2016 4,600 Balance, 12/31/16 $ 8,200 Robert A. Zimmermann President Broad Brook Coalition January 6, 2017