Bacillus stearothermophilus in soils of Iceland.

Bacillus stearothermophilus was found in Icelandic soils. Of the 33 strains studied, only four grew at 25 C. Temperatures as high as 27 C in bare soil at a depth of 1 to 1.5 cm were measured at the collection site. However, to demonstrate growth the cultures had to be incubated for 3 weeks, and soil temperatures remained at 27 C only for shorter periods of time.