50 PRINCIPLES OF FARM PRACTICE 



Space will not permit a description of the entire list of 

 soils included in the classification made by the United States 

 Bureau of Soils. It will be sufficient in this brief discussion 

 of soil management to include only those already mentioned; 

 sandy, sandy loam, clay, and clay loam. 



Sandy soils. We have seen that these soils are composed 

 of coarse particles. Such soils are easily worked and are 

 therefore valuable for special kinds of farming, such as truck 

 farming, where much work with hand tools is required. 

 They are also easily warmed, a property that is very desirable 

 when a long growing season or an early crop is needed. This 

 property is due to the fact that water readily drains from 

 sandy soils, so that most of the heat received from the sun 

 is used in increasing their warmth instead of in evaporating 

 the water. Crops may often be started in sandy soils two 

 weeks earlier than in heavier soils. 



But sandy soils have two serious defects; a small water- 

 holding capacity, and an insufficient store of plant-food 

 materials. To correct these defects is the greatest problem 

 in the management of sandy soils. 



The water-holding capacity may be increased by the 

 application of organic matter, such as manure. Such material 

 is capable of holding a large amount of capillary water. 

 Besides, when it fills the spaces between the larger particles 

 of sand, the water-holding power of the sand itself is increased. 

 To a certain extent, water may be controlled by handling the 

 soil in such way as to keep the particles close together, es- 

 pecially by plowing and rolling. If a plow with a sloping 

 moldboard is used in plowing sandy soils, the furrow slice 

 will be turned without breaking much, thus tending to make 

 the soil more or less compact. The use of the roller after 

 leveling the ground with a harrow will also aid in compacting 



