PHYSICAL, PROPERTIES OF SOILS 



103 



differences in rooting habits. Further, the character of root 

 growth is also related to the kind of tillage which should be given. 

 Crops whose roots extend near the surface of the soil should 

 not have these roots cut by deep cultivation. 



Fig. 29. Distribution of roots of corn, Kansas. 



Exhibition specimens of roots are secured in the following 

 manner. 1 A block of soil is cut out, with the plant in the center, 

 and a wooden frame covered with one-half inch mesh wire netting 

 is slipped over it. Plaster of Paris paste is then poured on the 

 top to hold the plant and large numbers of sharpened wires are 

 pushed through the soil and fastened to the netting, to hold the 

 1 Kansas Bulletins 75, 127; North Dakota Bulletin 43, 64. 



