38 



ALFRED DACHNOWSKI 



vegetation and any one factor of the environment, yet it is pos- 

 sible to make such a correlation within the area here investi- 

 gated, where there is a certain uniformity in regard to the chemi- 

 cal character of the soil. An analysis of Ohio peat shows the 

 following range in chemical composition: 



Chemical Analysis of Ohio Peat 



It would be interesting to determine the percentage of ash in 

 the herbs and shrubs, and in the wood of such trees as form the 

 principal covering of a peaty basin. The analyses reported by 

 Sargent in the Ninth census of the forest trees of North America 

 give the percentages for trees common to bogs. The data are 

 interesting in showing that the majority of the trees frequenting 

 bogs have a percentage of ash less than 0.50, and only a few of the 

 deciduous species occurring on peat deposits have a percentage 

 of ash greater than 1.00. The belief is widespread that the fer- 

 tility of a soil may be judged from the study of the chemical 

 character of the soil, and that soils markedly deficient in phos- 

 phates, potash, and other salts should be looked upon as barren 

 and sterile. But comparisons of the vegetation of peat areas 

 differing so widely in mineral constituents from land soils point 

 to the fact that differences in mineral components are trifling as 

 compared with the biological processes in the substratum and 

 the differences in available water. There is little credence to be 

 placed in the theory, as now held, of soil exhaustion, as any study 

 or European conditions alone will show. Fuller knowledge of 

 soil processes, of reduction action, sanitation, and available water 

 will control the danger of soil deterioration more satisfactorily 

 and economically. 



The successions from the aquatic type to forests epitomize 

 an ancient vegetation cycle. Elsewhere (American Journal of 

 Science, 32:33-39, 1911) the writer has pointed out the probable 



