24 THE FIRST BOOK OF FARMING 



can we control them in their action for the benefit 

 or injury of plants? 



We will begin this soil study with an excursion 

 and a few experiments. 



Go to the field. Examine the soil in the holes 

 dug for the root lessons, noticing the difference 

 between the upper or surface soil and the under or 

 subsoil. Examine as many kinds of surface soils 

 and subsoils as possible, also decayed leaf mould, 

 the black soil of the woods, etc. If there are in the 

 neighborhood any exposed embankments where a 

 road has been cut through a hill, or where a river 

 or the sea water has cut into a bank of soil, visit 

 them and examine the exposed soils. 



Experiment. Place in separate pans, dishes, 

 plates, boxes, or on boards, one or two pints each 

 of sand, clay, decayed vegetable matter or leaf 

 mould or woods soil, and garden soil. The soil 

 should be fresh from the field. Examine the sand, 

 clay and leaf mould, comparing them as to color ; 

 are they light or dark, are they moist or not? Test 

 the soils for comparative size of particles by rub- 

 bing between the fingers (Fig. 19), noticing if 

 they are coarse or fine, and for stickiness by squeez- 

 ing in the hand and noting whether or not they 

 easily crumble afterwards. 



Experiment. Take samples, about a teaspoon- 

 ful, of sand, clay and leaf mould. Dry them and 

 then place each in an iron spoon or on a small coal 

 shovel and heat in stove to redness. It will be found 

 that the leaf mould will smoke and burn, and will 



