88 CHEMICAL MANURES. 



a calm day for spreading broadcast ; in case of wind, some may be 

 lost. 



I will not go again over what I have said of the advantages the 

 chemical fertilizer has over the manure, by the power it gives of 

 varying the composition of the fertilizer, but I must insist on the re- 

 sources drawn from their use to overcome the effects of an unfavor- 

 able season. When the winter has been severe and prolonged beyond 

 the ordinary limits, grain and seeds of all sorts are often very much 

 injured. With 177 pounds of sulphate of ammonia,. or 311 pounds 

 of nitrate of soda, mixed with 177 pounds of plaster, spread as a 

 covering in the beginning of March, in a few days we can change the 

 condition of the crop and be certain of a harvest. The effect of a 

 top-dressing of this manure is truly magical. 



But here there are also precautions necessary ; you must not wait 

 later than the middle of March. Given in April and May, it throws 

 such extraordinary activity to the plant that the maturing of the grain 

 is retarded, and consequent on the exaggerated development of the 

 straw the grain is malformed there is but little grain, and that is 

 stunted. 



Top-dressing with manures, by the certainty and rapidity of action, 

 offers a resource of inestimable value to the agriculturist/ 



When the autumn is rainy and the sowing late for want of time, 

 the fertilizers can be used as a top-dressing after the grain is well up. 

 It is certainly the best method to spread the fertilizer before sowing, 

 but when that has been impossible, you should not hesitate a top- 

 dressing will assure a good harvest. Now with manure this is use- 

 less. 



In the spring use only sulphate of ammonia or nitrate of soda as 

 a top-dressing. These two products may suffice in extreme cold. I, 

 however, prefer to associate them with 177 pounds of acid phosphate 

 of lime the acre, mixed with 177 pounds of plaster. 



EQUALIZATION OF CULTURE. 



I have already told you that a judicious agriculturist must take 

 account of what the soil receives and what it loses. He ought every 

 year to make a balance of his cultures, and regulate the quantities 

 of fertilizers to satisfy these two laws : 



1. Give the soil more acid phosphate of lime, more potash and 

 more lime than the harvest has taken from it. 



2. Give it 50 per cent, of the azote of the harvests. 



Finally, to put each one so he can make this balance himself, 

 which is done exactly when done with discrimination, the following 

 table is given, showing the composition of those plants which form 

 the chief rotations. I must remark that all these analyses are from 

 plants harvested from the farm of Vincennes, and all grown under 

 the same conditions that is to say, with the complete fertilizer, 

 where azote enters at 71 pounds the acre. 



