Moorhead and Sinsabaugh developed a model of decomposition that integrates the dynamics of changing litter chemistry with microbial community interactions. Unfortunately, few studies provide data of sufficient resolution to test this guild-based decomposition model (GDM). However, Berg and Johansson defined empirical limit values to litter decay based on a review of 128 decomposition studies of 21 litter types at 38 sites. A limit value is the level of decomposition (mass loss) at which decay either stops or continues at a greatly reduced rate. The limit value is approximately the asymptote of mass loss, i.e., a higher limit value represents greater decay. In general, limit values are negatively related to initial nitrogen and lignin concentrations and positively related to initial manganese and calcium concentrations. These findings are consistent with the model results of GDM, which provides a mechanistic explanation for these empirical observations and projected patterns of microbial community dynamics. Osono recently evaluated decay of 14 litter types in Japan, with reference to the limit value concept, but including detailed litter chemistry. GDM predictions of final holocellulose, lignin and LCI values were highly correlated to observations at the proposed limit values, providing an independent validation of the model.