SOIL FORMATION 



29 



LABORATORY EXERCISES 



Exercise I. — Classification of soils. 



A study of the various kinds of soils must nec-v, 

 essarily be made in the field. No one locality 

 affords examples of all the different kinds of soil 

 listed in Chapter III. In some places only one or 

 two classes may be available. In any case make 

 all possible use of the materials, studying each 

 soil as to origin, parent rock, color, depth, sub- 

 soil, organic matter, drainage, general fertility 

 and crop adaptability. 



Exercise II. — Use of the soil auger in taking 

 soil samples. 



Material. — Soil auger and jars or bags for 

 samples. 



Procedure. — Explain the construction of a soil 

 auger and then proceed with the taking of a sam- 

 ple of the first eight inches of soil, removing the 

 soil in two portions. Then clean out a hole 

 larger than the auger worm to prevent contami- 

 nation of later samples and take the second eight 

 inches in the way already described. Place sam- 

 ples in bags or jars for future reference or exhibi- 

 tion. Be sure that the samples are representative ger for taking soil 

 of the soils to be studied. samples. (A) 



These samples may be used later in the tests handle, (B) joint, 

 for organic matter, acidity, water retention, and modified^utTing 

 other demonstrations according to directions in the edge, 

 laboratory exercises to be found elsewhere in the 

 book. 



Au- 



