Acadia National Park vegetation program invasive plant management, forest pest monitoring, and native plant stewardship 2024 annual report

Lanning, Emma; Wheeler, Jesse; Jobe, Devon

From the executive summary: "In 2024, the Invasive Plant Management Team (IPMT) surveyed 736 acres for invasive plants in Acadia National Park (ANP), covering forest and wetland areas on Mount Desert Island, the Schoodic Peninsula, Isle au Haut, and two other islands managed by the National Park Service (NPS). The IPMT treated .25 infested acres (over 1000 square meters) in total, visiting 83 field sites during the 2024 season. IPMT crew members contributed a total of 1383 work hours to these treatments and surveys. Of the 23 targeted species, glossy buckthorn (Frangula alnus) accounted for about 60% of the total time spent actively managing invasive plants. These efforts continue to support major restoration projects, including the big three under the Wild Acadia Initiative: Great Meadow Wetland, Bass Harbor Marsh, and Summits. This is the second year we have worked with Schoodic Institute scientists to study the effects of native plantings to suppress glossy buckthorn growth in Great Meadow and Bass Harbor Marsh. After establishing 15 study plots to test whether planted native shrubs or graminoids compete well with invasives last year, restoration crews added 3 plots in Great Meadow and 3 plots in Bass Harbor Marsh in 2024. We also continued our restoration work on the mountain summits of Sargent, Penobscot, and Cadillac. With exceptional assistance from community volunteers and youth groups, we transported over 4000 pounds of soil to these summits and established 41 new restoration plots covering 64 m2. We are continuing to test whether sowing native plant seeds improves revegetation rates. Over the 2023 and 2024 seasons, the IPMT surveyed and treated glossy buckthorn across the entire Bass Harbor Marsh field site, a heavily infested area approximately 20 acres in size. In 2024, the crew spent 225 hours over 6 visits working in 95 acres of Bass Harbor Marsh and the surrounding Marshall Brook watershed. We spent an equal amount of time (219 hours) in Great Meadow, where we took advantage of the drier conditions this year to treat mature, fruiting glossy buckthorn along the main channel of Cromwell Brook. We continued to collect seeds from native grass and shrub species in Great Meadow that will be grown for active restoration efforts in this wetland complex. The vegetation program assisted state and federal agencies in monitoring forest pests & pathogens such as the emerald ash borer, southern pine beetle, beech leaf disease, and hemlock woolly adelgid (HWA). We continued to monitor hemlock trees for HWA and collaborate with neighbors on biological control releases of Laricobius predator beetles at Jordan Stream. We removed browntail moth winter webs (and their toxic-hair-covered caterpillar residents) from visitor use areas on Mount Desert Island and the Schoodic Peninsula. We recorded far fewer webs overall than in recent years, hopefully translating to a reduction in emerging caterpillars in spring 2025." Locations Example: /STUDY LOCATIONS:/ /MOUNT DESERT ISLAND/Bass Harbor Marsh/Cadillac Mountain/Canon Brook/Cromwell Brook/Duck Brook Road Wetland/Great Meadow/Kent Field/Marshall Brook/Marshall Marsh/Penobscot Mountain/Sargent Mountain/ /ISLE AU HAUT/ /SCHOODIC/