General layout for forest sample plots on Watershed 6:

The watershed is gridded into 208 contiguous 25 x 25 m units.  In 1965, a 10 x 10 m plot within each grid unit was used to census live trees >1.5 cm dbh.  Smaller 1 x 1 and 2.5 x 2.5 m plots were used for counting seedlings and saplings.  In 1977 and all following samplings, the diameters (dbh) were measured for all trees >10 cm (live and dead) on each of the 208 25 x 25 m grid units (i.e. the entire watershed).  In 1982 and 1987, the >2 to <10 cm diameter trees (live and dead) were measured on 32 and 35 of the 25 x 25 m grid units, respectively. In 1992 and 1997, the >2 to <10 cm diameter trees were measured on a 3 meter wide strip in each of the 208 25 x 25 m grid units.