As part of a study designed to test the hypothesis that single large quantity rainfall events would result in higher rates of root decomposition than small frequent rainfall events or no supplemental water, we sampled the microarthropods associated with the decomposing roots. We hypothesized that supplemental water would not only affect the rates of decomposition but would also affect the species composition and biomass of the micrfauna feeding on the microflora on the roots. We further hypothesized that the successional trends in microarthropod populations observed on buried litter by Santos and Whitford (1981) would be similar on decomposing roots.