Hubbard Brook Experimental Forest is an area of land in the towns of Woodstock, Ellsworth and Thornton in the White Mountains of New Hampshire that functions as an outdoor laboratory for ecological studies. It was initially established in 1955 by the United States Forest Service for the study of the relationship between forest cover and water quality and supply. Forest land management In 1955 the first tract was dedicated in the Hubbard Brook watershed, just west of the village of West Thornton, New Hampshire. The first stream in the forest was fitted with monitoring devices in 1956. Subsequently, seven additional headwater streams and their associated watersheds were delimited for study. Each such zone functions essentially as a closed environmental system. Since efflux of water, minerals, and water-bound organisms leaving each watershed (and leaving the entire forest as well) can be monitored, the effects of changes experimentally introduced into the system can be measured. Hubbard Brook Ecosystem Study For the first five or six years after its establishment the HBEF was used for research in forestry but soon its value for study of the forest ecosystem was recognized and it attracted the interest of researchers from major universities. The work at Hubbard Brook has led researchers there and elsewhere to try to model or better understand the complex forest ecosystem, including its interaction with humans. HBEF research teams have succeeded in elucidating a number of vexing environmental problems, most notably the harmful effects of acid rain. The forest preservation the research promotes helps to protect watershed chemistry, ambient humidity, seasonal temperature fluctuations, and wildlife habitats. History The idea for using the small watershed approach being used at Hubbard Brook for studies of elemental budgets and cycles was born with Professor F. Herbert Bormann of Dartmouth College, who began taking his botany classes for field trips to this area of the White Mountain National Forest in the early 1950s, and Forest Service scientist Robert Pierce. Bormann proposed to Pierce that the area set aside by the Forest Service for watershed studies be used for closed-system ecological studies. In 1960, soon after the establishment of HBEF, ecologist Gene Likens and geologist Noye Johnson, both from Dartmouth, joined the research team. In 1963, the group received a $60,000 grant from the National Science Foundation to study "Hydrological-Mineral Cycle Interaction in a Small Watershed". This study evolved into the series of longitudinal studies now referred