A plaster cast method for determining soil bulk density

The plaster cast method for determining bulk density is an excavation method that uses dental plaster to form a cast of the excavation volume. Bulk density measurements using the plaster cast method were compared against measurements using the clod and core methods. Results from the plaster cast method were not significantly different (P< 0.05) from the clod and core methods for coarse-textured soils with loose consistence and minimal macropores. The plaster cast method is especially useful under soil conditions that limit the use of the clod or core method, such as soils with loose consistence, abundant rock or gravel content, thin horizons, or sloping topography, but may not be suitable for use in soils with abundant macropores.