Soils 71 



crease very rapidly when conditions are favorable. Many 

 of the diseases of plants and animals are caused by bac- 

 teria. This does not mean that all are harmful ; many 

 are decidedly beneficial. 



These germs cause the decay of the coarse organic 

 matter of the soil and assist in the formation of the more 

 useful hiunus. They are exceedingly important in con- 

 nection with the nitrification, that is, with the transfor- 

 mation of nitrogen from the unavailable form to the 

 nitrates, which are taken up by crops. Certain forms of 

 bacteria also assist in fixing the nitrogen of the air and 

 in making it into a food for plants. This is done mainly 

 in connection with the legume crops, although some forms 

 fix nitrogen without the aid of legumes. 



SELECTING A SUGAR-BEET SOIL 



As previously stated, sugar-beets do not absolutely re- 

 quire any given kind of soil ; they are successfully raised 

 on almost every type of soil when other conditions are 

 favorable. This does not mean that all soils are equally 

 well suited to raising the crop. Usually it does not pay 

 to raise beets on any but well-adapted soils. 



A number of conditions must be strictly avoided. One 

 of these is a hardpan near the surface that would inter- 

 fere with the deep rooting of the beets. Another condi- 

 tion to be avoided is a water-logged soil. Of course 

 this can usually be overcome by drainage, but as a rule 

 beets should not be planted until after the drain is in 

 operation. 



So far as texture is concerned, a loam is best adapted 



