In a community of widely spaced perennials, mostly shrubs, in the cold desert of western Utah, total accumulated organic mass (excluding the small amount of humus) is about 1,770g./m.2. Of this total, 240 g. are above the ground and 1,530 g. below. Of the latter, 295 g. is underground litter. About half of the 1,235 g. of roots are in the surface 30 cm. of the soil, about 0.3 of them in the second 30 cm., 0.15 in the third, 0.03 in the fourth, and 0.01 of them occur below 120 cm. to about 135 cm. Coarce roots (> 2 mm. in diameter) are found only in the immediate vicinity of plants and are unimportant below the 15-cm. depth. Fine (