36 SUCCESSFUL FARMING 



soil to which large amounts of water were applied by irrigation were found 

 to have penetrated to a depth of only about three inches in the course of 

 as many months. This suggests that such fertilizers should be distributed 

 in that zone of the soil where root activity is most marked, in order that 

 the plants may utilize the fertilizer as fully as possible. All of this has a 

 bearing upon the fertilizer practices which will be discussed in a sub- 

 sequent chapter. 



Plasticity and Ease of Cultivation. Soils of fine texture are very 

 plastic when wet, and clay soils in this condition tend to adhere to cul- 

 tural implements, wheels of vehicles and the feet of animals. Such soils 

 should not be tilled when they are wet. The movement of the soil par- 

 ticles upon one another when in this condition causes them to be cloddy 

 and hard when they dry out. It furthermore gives rise to what is known 

 as puddling, and prevents the free movement of water and air through 

 the soil. This is well illustrated by a clay road in the spring when wagcns 

 pass over it and form ruts while it is in a wet condition. These ruts will 

 often become filled with water, which escapes only by evaporation, none 

 of it finding its way through the soil below. The fine-textured soils, 

 when not well supplied with organic matter, tend to run together and 

 become very compact and difficult to cultivate. This condition can be 

 alleviated to a certain extent by avoiding tillage operations when too wet, 

 and also by the application of organic matter in the form of manure or 

 green manuring crops. Likewise, this condition is improved by the 

 application of lime, which causes a flocculation of the soil particles; that 

 is, causes them to gather into little groups with larger spaces between 

 these groups. 



The sandy soils and those containing a liberal amount of sand are 

 less affected by rains, are more easy of cultivation and do not call for as 

 great precautions in their tillage. Such soils when wet do not adhere to 

 cultural implements and the feet of animals as do the heavy soils, and the 

 roads made of such soil are often as good or better immediately after rains 

 than they are when in a dry condition. 



Texture Affects Crop Adaptation. Heavy clay soils and those con- 

 taining large amounts of silt are generally best adapted to the grasses such 

 as timothy, blue grass, orchard grass and redtop, and to wheat, rye and 

 what is commonly known as the heavy truck crops, such as cabbage, 

 tomatoes and asparagus. The soils known as loam, which are of medium 

 texture, are better adapted to such crops as corn, oats, barley, buckwheat, 

 peas, beans, clover and potatoes. The soils of light texture, known as 

 fine sand and sandy loams, are also well adapted to potatoes, beets and 

 all tuber and root crops, and are also extensively used for the early truck 

 crops, such as spinach, lettuce, early potatoes, early peas, etc. Some of 

 the very lightest sands, such as are found in certain parts of Florida, are 

 especially adapted to the growing of pineapples. In general, the poma- 

 ceous fruits, such as apples and pears, will do well on fairly heavy soils, 



