Title: Vegetation, Landcover, and Fuel Mapping of the Ossipee Pine Barrens, Carroll County, NH (2005)
Author: Jeff Lougee, The Nature Conservancy
Abstract: Vegetation, landcover, and fuels were mapped within an 8,166-acre area of the Ossipee Pine Barrens in Carroll County, New Hampshire. The Nature Conservancy divides the Ossipee Pine Barrens landscape into three sections: White Lake State Park, Pine Barrens East, and the West Branch Pine Barrens. The mapping area covers the entire West Branch Pine Barrens, and a small portion of Pine Barrens East (see Map 1). The mapping area includes extensive amounts of pitch pine/scrub oak vegetation, hardwood forests, and wetlands. There are approximately 2,300 acres of pine-barrens vegetation, 1,000 acres of wetlands, and 2,650 acres of other forest types, including white pine dominated softwood stands, mixed hardwood-conifer forests, and pure hardwoods. Nearly 1,500 acres of the mapping area is developed, with much of this occurring in former pine-barrens areas.
The Ossipee Pine Barrens is a ca. 3,000-acre occurrence of globally rare northern pitch pine/scrub oak barrens. It is New Hampshire’s last viable occurrence of a pine-barrens, and is home to a number of rare and endangered species, including the only known occurrences in the state of several globally rare moth species. The site is also one of the few places in New Hampshire with robust populations of declining shrubland and early successional birds.
Northern pitch pine/scrub oak barrens are believed to be maintained by periodic fires that occur every 25 – 50 years (Sperduto et. al. 2000). These fires have played a critical role in the maintenance of these natural communities by releasing nutrients, recruiting fire adapted species, removing fire intolerant vegetation, promoting seed dispersal, creating diverse “seral” or “structural” stages, and preparing a seedbed for species, like pitch pine, that require mineral soil for seedling establishment. It has been nearly 50 years since the Ossipee Pine Barrens has been subject to ecologically beneficial fire. In the absence of fire, fuel loads have accumulated to hazardous levels in many areas, placing both the human settlements in Ossipee and the ecosystem at risk. Additionally, the lack of fire has led to ecosystem degradation in the form of encroachment by fire intolerant species like white pine and some hardwoods, and a noted loss of open habitat types.
This mapping is part of a comprehensive ecosystem management program launched by The Nature Conservancy in 2003. This program has simultaneous goals of restoring the integrity of the Ossipee Pine Barrens ecosystem, while reducing the hazardous fuels that have accumulated over the past 50-100 years. An improved understanding of the vegetation, landcover, and fuels at the site will enable the Conservancy, along with its partners, to effectively monitor the Ossipee Pine Barrens ecosystem over time, plan for restoration activities such as prescribed burns and other fuel treatments, and provide critical information to assist local communities with wildfire suppression.
Cover types were mapped using recent aerial photography and high resolution satellite imagery, with data from over 150 points on the landscape used to inform the mapping. Four thematic maps have been developed, including:
· Vegetation and landcover (Map 3)
· Generalized vegetation and landcover (Map 4)
· Fuel types (May 5)
· Crown fire hazards (Map 6)
Forty distinct cover types were mapped to illustrate vegetation and landcover across the landscape. These types follow several existing classifications, including Dacey (2003), Finton (1998), and Sperduto and Nichols (2004). The vegetation and landcover types show the distribution across the landscape of pine-barrens “seral” or “structural” stages, and when possible New Hampshire Natural Heritage Bureau natural communities types. The generalized vegetation and landcover provides a grouping of the detailed types into 8 broad categories for quick reference. Fuels are categorized into 12 types based on the standard fuel models developed by the United States Forest Service (Anderson 1982) and custom fuel models developed for the Ossipee Pine Barrens (Patterson 2001). The crown fire hazards map classifies areas into high, moderate, or low risk for crown fires. This map also shows the location of potential fire breaks and safety zones.
This is the first iteration of this mapping for the Ossipee Pine Barrens, and it is anticipated that future mapping exercises will include the remainder of Pine Barrens East and White Lake State Park. This expanded mapping will enable the Conservancy and its partners to develop a more comprehensive, landscape level approach to management at the site. It is also important to note that this mapping only provide a snapshot in time of the vegetation, landcover, and fuels at the site. This data will need to be updated at regular intervals in order to capture the sometimes rapidly changing landscape at Ossipee.