Bartlett Experimental Forest

The White Mountain National Forest, including the Bartlett, was purchased under the Weeks Act of 1911. In the late 19th century, the area was selectively logged for high-value species, first eastern white pine and red spruce and later sugar maple and yellow birch. Logging railroads were laid and hardwood stands were clearcut for locomotive fuel. The lower third of the Bartlett was logged and some portions were cleared for pasture. Upper portions were progressively less impacted with increasing elevation. Although fires are relatively rare, the 1938 hurricane did widespread damage. High-grading resulted in more American beech, so that when the beech scale-Nectria complex (beech bark disease), arrived in the 1940s, it caused substantial damage and continues to influence stand dynamics. An ice storm in 1998 was the most recent widespread natural disturbance, affecting mostly higher elevation stands. Occasional windstorms are common, but of relatively small scale.

Climate

Summers are warm with high temperatures frequently above 32 °C. Winters are cold with low temperatures often reaching -5 °C. Average annual precipitation is 1,270 mm, well distributed throughout the year. In winter, individual storms can drop more than 600 mm of snow, which most years accumulates to depths of 1.5 to 2 m.

Soils

The soils on the Bartlett are spodosols that developed on glacial till derived from granite and gneiss. The soils are moist but usually well drained. In places, the soil is shallow and boulders and rocks are common throughout the forest.

Vegetation

There are areas of old-growth northern hardwoods with American beech, yellow birch, sugar maple, and eastern hemlock the dominant species. Even-aged stands of red maple, paper birch, and aspen occupy sites that once were cleared. Red spruce stands cover the highest slopes, and eastern white pine is confined to the lowest elevations.

Facilities at the Bartlett include an office and laboratory space, a conference room, and quarters for up to 25 people.

Lat. 44°2′39″ N, long. 71°9′56″ W

Research, Past and Present

For the first 50 years, research on the Bartlett focused on managing northern hardwood stands for timber. An array of silvicultural prescriptions was applied, including single-tree selection, group and patch cutting, clearcutting, and diameter-limit harvesting. Although these are among the longest running studies in this forest type, many management questions about thinning regimes, tree-quality development, etc. remain and silvicultural research continues. Silvicultural treatments create a range of stand compositions and structures that are ideal for wildlife habitat studies. For the past 20 years, relationships between vegetation management and needs of wildlife throughout their life cycles have been investigated intensely. Such research focuses on amphibians, small mammals, and birds. Since 1995, the Bartlett has become a primary site for tests of emerging airborne and spaceborne remote-sensing technologies, including imaging spectrometry, imaging laser, and radar systems. These technologies are evaluated for their ability to estimate forest composition, structure and growth, and ecosystem processes such as nutrient cycling and carbon storage. This research, though primarily at the landscape or broader scales, critically depends on the long-term detailed records from the Bartlett.

Major Research Accomplishments and Effects on Management

Northern hardwood forest management in New England is based largely on research done at the Bartlett. Regeneration methods and early stand management have been influenced by studies there, as have recommendations for managing habitat for wildlife. Research on the Bartlett has been instrumental by understanding forest response following disturbance and in providing reference data for field and remote sensing studies aimed at understanding nutrient cycling, growth, and carbon storage. Technology transfer is a major function, with numerous workshops and tours annually.

Research Opportunities

Opportunities for studying all aspects of ecology and management of northern hardwood forests in New England are nearly unlimited on the Bartlett, and manipulative experiments are possible in collaboration with New England scientists. Project staff will facilitate nonmanipulative studies that do not conflict with the long-term mission of the forest.