1 68 BACTERIA AND SOIL FERTILITY 



for large seeds, such as soybeans, is very satisfactory. The seeds 

 are thoroughly moistened by a lO per cent solution of glue and 

 sufficient dry pulverized infected soil sifted on to absorb all of the 

 moisture. The seed is shovelled over a few times. Such infected 

 seed should be planted very soon or else spread out to dry to 

 prevent mold action. Neither infected seed nor soil should be 

 long exposed to bright sunshine, as this is very destructive to the 

 bacteria. 



Where the old plants are to be inoculated, a few hundred 

 pounds of soil may be obtained from an old infected field spread 

 on the new field and harrowed. 



Dr. C. B. Lipman gives the following method of inoculating 

 beans, and in a modified form it can be used for other legumes: 



"Method Involving the Use of One Commercial Culture : 

 — Prepare one-half barrel full of good loam soil (150 pounds) 

 with sufficient water to make about optimum moisture conditions. 

 This soil can be kept in a shallow vat about a foot in depth or in 

 some other convenient receptacle where it can be well aerated. 

 Purchase one commercial culture from any of the commercial 

 firms selling legume bacterial cultures, choosing a culture for 

 beans of the variety desired. The amount usually sold in a 

 culture for one acre is sufificient. Shake this up with a few quarts 

 of boiled water. The shaking should be continued for about ten 

 minutes to get all of the bacteria in suspension. Pour this sus- 

 pension all over the surface of the soil in the vat and add to the 

 solution about one-quarter of a pound of ordinary sugar per one 

 hundred pounds of soil used in the vat. This should be distributed 

 as evenly as possible through the soil and the latter thoroughly 

 mixed with a spade or hoe, thus distributing both the sugar solu- 

 tion and the culture. After that the inoculated soil is to be kept in 

 a warm place like a kitchen or a warm stable and the moisture 

 content maintained at optimum until you are ready to use it for 

 the inoculaiton of beans when they are planted. It is well to 

 allow a period of two or three months for such incubation. 



"At the end of the incubation period, or when getting ready to 

 plant, shake up some of the inoculated soil with clean water for a 



