The Soil Biotron at the University of Michigan is an underground laboratory that is designed to facilitate the study of life processes in the soil. From the beginning, the Biotron was intended to be a special-purpose research facility that would provide the opportunity for a broad range of interdisciplinary investigations and manipulative studies in the soil. The Biotron was also an attempt to improve the ability to use statistically appropriate replication in soil studies. Traditional methods of studying soil processes have often had associated large measurement errors.