Watershed 5 is the fourth in a series of forest manipulations at the watershed scale at the Hubbard Brook Experimental Forest to test the ecosystem effects of various forestry practices.  In the late 1960s and 1970s there was considerable controversy about the ecological ramifications of the growing practice of clear cutting forests throughout the U.S. The opportunity arose at the HBEF to do a whole-tree harvest experiment on one of the watersheds (W5) which had been hydrologically and geochemically monitored for a number of years previous to the planned harvest. The area of Watershed 5 is 22.5 ha. 

A 25 x 25 m square grid system was surveyed onto Watershed 5 in 1981 and 1982. Permanent marker stakes were set at all the corners. In 1982 a complete inventory of all the trees > 10-cm dbh was made. The 2 - <10-cm dbh trees were measured on a stratified random selection of the 25 x 25 m grid units. A total of 360 25 x 25 m grid units comprise the watershed and 42 of these were sampled for the trees 2 - <10-cm dbh.  A set of 60 quantitative soil pits were excavated and sampled in the forest in 1983. The forest was whole-tree harvested during the fall of 1983 through the winter of 1984. Most trees were felled with a feller buncher, but trees larger than about 50-cm in basal diameter were cut with chain saws.  Whole trees were forwarded to the bottom of the watershed and chipped. Logs of merchantable size and condition were set aside as saw timber.  The logging was finished by the spring of 1984. 

   There were a few "loose" ends in the manipulation.  The logger defaulted on the job in late winter of 1984.  The top of the watershed (several hectares) was not finished and an agreement was made to cut all the trees there, even though they were not removed immediately.  These trees were finally skidded off to the north of the watershed in the summer of 1985. They were piled outside the watershed boundaries, but not removed from the area.  In addition, the trees on about one hectare of steep "inaccessible" area of the watershed were cut, but not removed.

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