474 SOILS: PEOPUMTIJES AND MANAGEMENT 



ticed in greenhouses for a long time, principally for the 

 purpose of combating plant diseases. Its value in in- 

 creasing productiveness has been a consideration since 

 this phase of the subject has been emphasized by investi- 

 gations, and the treatment of " sewage-sick '' soils has 

 been shown by Russell and Golding ^ to be a practical 

 matter. It is as a means of studying the principles of 

 soil fertility, however, that the investigation of the sub- 

 ject of partial sterilization of the soil is of greatest im- 

 portance. 



1 Russell, B. J., and Golding, J. Investigations on "sick- 

 ness" in soil. Part 1. "Sewage sickness." Jour. Agr. Sei., 

 Vol. 5, pp. 27-47. 1912. 



Russell, E. J., and Golding, J. Investigations on "sickness" 

 in soil. Part 2. "Sickness" in glasshouse soils. Jour. Agr. 

 Sci., Vol. 5, pp. 86-111. 1912. 



