44 MASSACHUSETTS HORTICULTURAL SOCIETY. 



the atmosphere and soil together the gaseous. The ash comes 

 from the disintegration of the particles of soil, to some extent 

 through weathering as it is called, but mainly, I think, from the 

 decomposing action of the roots of plants. Almost any plant 

 growing in a clear glass vessel will so far decompose the glass 

 itself as to corrode or etch the surface, and if sutHcient time be 

 given will produce the appearance of ground glass. This action 

 takes place very slowly to be sure, but the millions of soil 

 particles give sufficient surface to the roots, so that the plant 

 obtains enough by which to continue its existence, and if all the 

 elements which it requires be in plentiful supply, the resulting 

 product will approach a maximum. Many of these elements do 

 occur in most soils in sufficient quantities for a full growth and 

 development of most plants, but a few do not. These, named in 

 the order of the relative amounts generally necessary, are Potash, 

 Nitrogen, Phosphoric Acid, Lime, and Magnesia. Hence, to grow 

 profitable crops these substances must be added to the soil in some 

 form so that the plant may obtain enough to satisfy its full needs. 

 Barnyard manure has always been looked upon as a complete 

 type of fertility. It consists largely of hay with more or less 

 grain, ground fine by the animal that, through digestion, withdraws 

 a small percentage of nutriment from it, and excretes the 

 remainder. If all the liquid and solid matters thus voided are 

 saved they constitute a very complete fertilizer. The solid 

 portion alone, however, is incomplete, or one-sided in composition, 

 as is also the liquid, which is the other sided. Neither one alone 

 can supply the place of the other, nor compensate for its absence. 

 It is found in practice, in the growing of fruits at least, that its 

 place can be supplied with other substances, both with economy 

 and better results. Barnyard manure like all organic substances 

 is available only after its decomposition, which requires two or 

 more years for its completion, and it is a serious economic question 

 if it be best ^to apply costly materials on which dividends are 

 unnecessarily postponed. Chemistry shows that the more valuable 

 constituents of barnyard manure can be supplied in commercial 

 substances, in better forms, at a cheaper rate and with surer 

 results. The average composition of fruit trees and vines, 

 together with the fruits, as shown by many analyses, led me to 

 believe that for satisfactory results, there should be applied to 

 each acre annually, not less than 100 to 120 pounds of potash, 40 



