Populations of Spore-forming Bacteria in an Acid Forest Soil, with Special Reference to Bacillus subtilis

Abstract

The distribution of Bacillus subtilis in a pine-forest soil has been investigated by using the fluorescent-antibody technique and dilution plating. In the acid, mineral horizon of the soil, the organism occurred mainly in the vegetative condition, while in the alkaline, mineral horizon it was mostly present as spores. Within these soil horizons, the bulk of the vegetative bacteria was found on organic matter particles, but of those found on mineral particle surfaces, almost all were on cryptocrystalline quartz particles with iron oxide inclusions.