AMONG SCHOOL GARDENS 



to be improved. There is still another division of 

 soils based upon the ease with which they may 

 be worked. Sandy soils are usually called '' light " 

 because they are easier to work, though in equal 

 quantities they really weigh more; for a cubic 

 foot of dry sand weighs i lo pounds and the same 

 amount of clay about 80 pounds. 



Soil, as thus far discussed, is that part of the 

 earth's surface sometimes called the ''top-soil" 

 in distinction from the ''subsoil". As the top- 

 soil practically holds all the humus, the subsoil 

 is virtually non-nutritious, disintegrated rock. 

 Accordingly, when we speak of soil, we usually 

 mean the top layer, whether a few inches or a 

 few feet in depth. This depth is all important to 

 the gardener, for under no circumstances must the 

 top-soil be destroyed or the subsoil be turned over 

 upon it. That will be the result if ploughing is 

 too deep or if, in grading, the top-soil be leveled 

 off or subsoil be dumped upon it. Between these 

 two soils there is usually a difference in color and 

 texture. 



A gardener or householder should see that in 

 the garden or about the home grounds every 

 particle of the top-soil shall be preserved. So 

 important is this, that a wise husbandman will 

 not harrow his land on a windy day lest the wind 

 carry oif in clouds of fme dust the food particles 

 so desirable for his crops. In grading, it is some- 

 times necessary to skim off the top-soil, level, and 

 replace it. Where the top layer is thin, and the 



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