PUOTEGTIVE MEASURES. 



A few simple observations will serve to illustrate the principles 

 npon which the methods of combatting unfavorable conditions of cli- 

 mate in respect of crops are based. What can we do to reduce the 

 effects of drouth? Our first observation is that only a part of the 

 water falling on the land leaves it bj' the way of streams and rivers. 

 The rest is evaporated from the surface of the soil or from plants. 

 Can we do anj^thing to reduce the loss from evaporation at the surface 

 of the soil? Let us try a simple c-xperiment. We will need a pair of 

 scales, two tin buckets holding about four quarts each, a peck of loam 

 and some water. The loam should be well mixed, free from stones 

 and large lumps. Place the loam in a box which is not water-tight, 

 cover it with water and allow the surplus water to drain ofE. Fill the 

 buckets with this wet earth, placing an equal weight in each. The 

 buckets of earth must be allowed to stand where they will be protected 

 from rain and freely exposed to the air. The earth in one should be 

 left imclisturbed. So soon as the surface of the earth in the other 

 is dry enougli it should be stirred to a depth of about one inch, and 

 this stirring should be repeated every few days in order to keep a 

 layer of loose earth on the surface. Weigh the buckets of earth every 

 few days and note the results. Why does one lose weight faster than 

 the other? Let us see if this can be made clear to yoii by using a 

 familiar fact as an illustration: How does the oil pass from the lamp 

 reservoir to the flame? What would be the result if all except a few 

 of the fibers of the wick were cut or if the top end of the wick should 

 be made of material that did not readily permit the movement of the 

 oil through it? AYhen you liave thought out the answers to these 

 questions, you liavc the principle involved in the use of the mulch 

 blanket of fine earth which is so valuable in conserving soil moisture 

 and in carrying crops through prolonged periods of drouth. Frequent 

 shallow cultivation is of great value in reducing the loss of water 

 tlirough evaporation from the surface of the soil. 



Can we do anything to increase the water kept stored in 

 the soil and to decrease the amount that is lost in streams? 

 Do you ]iot know of hill sides where heavy rains make gul- 

 lies and the water carries the soil away? or of fiat lands 

 on which water stands until it "dries up?" Why is this? 

 Because the water cannot enter the earth as fast as it falls. Often the 

 washing does not l>egin as soon as the rain begins to fall; in this we 

 may find the key to a solution of the matter. If the ground has been 

 plowed five inches deep it may take up the water until this five-inch 



