1910.] 



PUBLIC DOCUMENT — No. 31. 



41 



face, and the lower layer was sampled at a depth of 3 feet. A 

 fourth sample was procured from the same locality, but was 

 taken from a pile of air-dried peat which had been excavated 

 several months previous and had been allowed to lie exposed to 

 the oxidizing agencies incidental to the weathering process. 



The table of analyses has been prepared on the basis of 100 

 parts of dry matter, the method used for the determination of 

 the availability of the nitrogen being the alkaline permanganate 

 method. 



Peat. 



Total 

 Nitrogen. 



Per Cent, of 

 Nitrogen Available. 



AVeathered peat, 



Top layer (first 18 inches), 

 Intermediate layer (18 inches to 3 foet), 

 Lower layer (below 3 feet) , 



In case of the samples examined it will be seen that the lower 

 layers contained less nitrogen, which was probably rather less 

 available than that in the upper layers. It may be seen, further, 

 that the weathered peat, although showing a smaller nitrogen 

 content than even the intermediate layer, apparently has a 

 slightl}' higher availability. These results seem to me very sig- 

 nificant. The weathered sample was a mixture of the peat 

 taken from the same locality to a depth of from 4 to 5 feet, and 

 yet v/e find that it leads in the availability of its nitrogen. This 

 indicates the possible beneficial effect of the weathering or 

 oxidizing process. 



It should not be understood that the above figures represent 

 the actual amount of nitrogen in the peat that is immediately 

 available as plant food. There is no certainty that laboratory 

 methods accurately indicate availability. They are as yet arbi- 

 trary, and much work needs to be done along the lines of vegeta- 

 tion experiments before we can definitely say just how much of 

 the nitrogen in any organic substance is available as plant food. 

 The results, however, are comparative. 



Peat is found in such immense quantities and is so widely 

 distributed throughout the country that it may n(tt be <>nt of 

 place to give it a careful study from an econQiuical standpoint. 



