A re-examination of surface litter decomposition studies in the northern Chihuahuan desert (New Mexico, U.S.A.) suggests mass loss patterns may be more closely regulated by abiotic precesses than originally thought. Although biological mechanisms have been proposed to explain the high rate of surface litter disappearance in this ecosystem, non-biological processes, such as the leaching of solubles and photochemical degradation of lignins, may account for much of the total loss. Results of some recent studies may be better explained when the probable contributions of abiotic factors are considered.