SELECTION OF PEAT LANDS FOR DIFFERENT USES 19 
Very few systematic observations of the influence of different min- 
eral salts, including lime and fertilizers, upon cultivated peat lands 
have been made thus far. It is recognized to be a great drawback 
to the work that the analyses made are not comparable, because of 
the employment of widely different peat areas and methods of work. 
On this account opinions have been at considerable variance as to 
the effect of mineral salts in promoting the decomposition of peat 
materials, in accelerating the activity of beneficial microorganisms, 
or in modh^ung the availability of salts and organic compounds for 
the growth of crops. There is also the problem of alkali salts on 
certain peat lands, a solution of which can be reached, here as in 
other questions, only when a uniform method of analysis is em- 
ployed. 
The outstanding feature of fertilizer analyses, reported by State 
experiment stations and other agencies, 4 is the deficiency of potash 
and phosphates. Accordingly, the continued use of potash salts for 
crops such as potatoes, onions, or sugar beets, which show a response 
to this fertilizer, has become profitable on nearly all types of peat 
lands. Phosphates have the advantage that they stimulate the 
activities of certain microorganisms; thereby they lead to a more 
thorough utilization of the organic material of fibrous-peat areas and 
to the formation of larger quantities of available plant-food constit- 
uents. 
Nitrogen, assimilable by crops, is most often deficient in coarsely 
fibrous peat layers. For this reason, frequent applications of soluble 
nitrate fertilizers are needed, in order to prevent injury to growing 
plants and to hasten the decomposition of the layers. The use of arti- 
ficially prepared bacterial culture does not, however, assure a natural 
and normal inoculation of this type of peat land or of the seeds of 
nonleguminous plants. The best natural method for obtaining avail- 
able nitrogen depends on the type of peat material, its proper prep- 
aration, and on the seasonal conditions. Moderately fibrous layers 
of peat, judiciously provided with lime, fertilizers, and an abundance 
of air and moisture, favor the fixation of free atmospheric nitrogen 
by bacteria. Suitable crop rotations are another means to this end. 
The liberal application of nitrogenous fertilizers is economically remu- 
nerative only with crops of high commercial value, grown under inten- 
sive cultivation. Before satisfactory results are obtained, it is often 
necessary to apply excessive and probably unprofitable quantities of 
potash and phosphate to restore a balance for plant growth. The 
conditions which favor losses of nitrogen are not well known, but 
fine-textured heavy peat soils show greater depletion of nitrogen 
than loose, light layers of peat. On the whole, a practical trial in 
the field from time to time affords the best method of determining 
the fertilizer requirements of individual peat areas or crops. It is 
a well-known fact that the fertilizer needs of peat soil can not be 
determined from their chemical analysis. 
Acidity in peat lands is of varying nature, the reaction being more 
or less influenced by the profile structure of the area and the differ- 
ences in soluble salts. The high content of carbonaceous substances 
but slightly broken down in peat lands of the profile series with digit 
2 in Plate 1 constitutes a reserve of potential acidity which is impos- 
* The following serial numbers refer to publications on fertilizer analyses in "Literature citied," at the 
nd of this bulletin: 1, 2, S, 4, 17, 19, 20, 23, 24. 
