414 MISCELLANEOUS FARM SUBJECTS 



fluence in producing a better physical or mechanical condition in 

 the soil to which they are applied. In fact, this value of improving 

 the texture is often far greater than that derived from the plant 

 food supplied. 



In another connection it has been pointed out that many farm 

 soils, even those that are unproductive and apparently worn out, 

 contain large amounts of plant food; and that this can be largely 

 corrected by improving the mechanical condition or texture. 



When manure is incorporated with a soil it greatly improves 

 the texture, loosening a heavy, compact soil, and binding together 

 a light, leachy one, making the soil more friable, warmer, more re- 

 tentive of moisture, and more congenial to plants in every way. 

 Some experiments conducted by King, at Wisconsin Station, showed 

 that manured land contained 18 tons more water per acre in the 

 upper foot of soil than similar land unmanured, and 34 tons more 

 in the soil to a depth of three feet. Manure exerts a quicker bene- 

 ficial influence on the texture of soils than green manures. Ma- 

 nures will also aid in equalizing the supply and distribution of water 

 in the soils; will make soils to which they are applied darker in 

 color, and exert a material influence in making soils warmer. Ma- 

 nured land is less subject to the denuding effects of wind and rain. 



Chemical Effects of Manures. Manures act chemically on soils, 

 as already stated, by adding new stores of plant food, and by their 

 decomposition in the soil they give off carbonic acid gas, which unites 

 with the soil waters and increases its dissolving action on mineral 

 plant foods. It also provides the formation of humates in the soil, 

 and thus renders inert mineral plant food more available. The 

 temperature of soils will be materially raised as a result of the 

 chemical actions. 



Bacterial Influences of Manures. In addition to supplying 

 plant food and vegetable matter, with their accompanying bene- 

 fits, farm manures introduce into the soil a variety of bacteria and 

 ferments, which also produce beneficial results. These bacteria, 

 though great in number, have not been studied much in detail, and 

 are little understood. It is very certain, however, that they are 

 helpful in increasing the supply of available plant food. Farm ma- 

 nures have often the advantage over green manures in that the fer- 

 ments introduced by the manure will result in an alkaline condition 

 of the soil, while that from the green manure will be acid. Hence 

 manure favors the nitrogen-gathering bacteria of legumes and nitri- 

 fying organisms. 



Professor Chester of the Delaware Experiment Station, has 

 found in a soil that had been liberally manured, and was producing 

 at the rate of six tons of hay per acre several times as many bacteria 

 as were found in the same soil which had little manure, and was 

 producing about one ton of hay per acre. 



Factors Influencing the Value of Manure. The factors which 

 influence the commercial and agricultural values of stable manures 

 depends upon the following: (a) The kind of animals; (b) the 

 age and condition of the animal; (c) the food of the animal; (d) 



