Soil samples were collected from two pits at the DIRT site on April 24, 1990. Oe+Oa horizon samples (Pit 2, designated as Oea) and L+F samples (Pit 1) were collected using a 15 x 15 cm template. Mineral soil samples were taken with plastic tubes measuring 5 cm diameter by 15 cm long.

Soils were collected from plots 3, 4, 5, 7, 18, and 21 on October 10-14, 1990. Samples were collected by both by horizon and depth. The O and A horizons were still intact at this time in the –OA treatment plots (5, 7, and 21).

Mineral soil samples were seived through a 2 mm sieve. Rocks and roots larger than 2mm were removed. Sieved material was subsampled for moisture and organic matter determination. Oea material was thoroughly mixed by hand, and then subsamples of each sample were taken for determination of air dry – 50C – 105 C - Ash free dry weight conversions. pH, %C, and %N were also determined.