284 Bulletin 38. 



In greenhouse work, or for the fertilization of citrus and 



other valuable trees, commercial fertilizers containing nitrogen 



may be used, such as Chile saltpeter, tankage, etc. But it would 



be wise to make use of the waste from the farm before purchasing 



expensive fertilizers for these purposes. 



R. H. Forbes, 



Department of Chewistrx 



HOME-MADE FERTILIZERS. 

 No. 31, April 15. 



It has been well said that " a thrifty farmer may be judged 

 by the size of his manure pile." This should be modified, how- 

 ever, for quality as well as quantity should be taken into consid- 

 eration. How often do we hear the statement made by farmers 

 that " I applied a certain number of loads of barnyard manure per 

 acre to my field," which means very little indeed unless the qual- 

 ity of the manure applied is taken into consideration. I have seen 

 barnyard stuff put upon land when it w r as not worth the labor of 

 hauling, owing to the fact that nearly all of the plant food which 

 it originally contained had been allowed, by improper care, to es- 

 cape. This, naturally, leads to the question of the losses to which 

 manure is subject. Barnyard manure is a very complex sub- 

 stance and undergoes very rapid changes, by which much of its 

 value may be lost if it is not properly cared for. Eoss is due to 

 two chief causes. First, fermentation, of which there are two 

 kinds, one of which, for its growth, requires an abundant supply 

 of air, while the other grows without air and will die when ex- 

 posed to it. The first of these ferments is the most active and 

 destructive. 



The second source of loss is by leaching or weathering. The 

 leaching, of course, is not the serious problem in Arizona that it 

 is in the more humid regions; yet serious loss of soluble plant food 

 may occasionally occur in this way. It is necessary, however, 

 that the manure be kept in a fairly moist condition ; the destruc- 

 tive fermentation spoken of above is thereby held in check, while 

 the coarse stuff, as straw, etc., is decomposed, and the plant food 

 which it contains made more available. 



