PERIODICAL LITERATURE 



SOIL, WATER, AND CLIMATE 



After taking issue with A. H. Hutchinson 



Influe-nce of ("Limiting Factors in Relation to Specific Ranges. 



Underlying Rock of Tolerance of Forest Trees." Botanical Gazette,. 



on Distribution 66:465-593, December, 1918) for overlooking 



of Jack Pine the factor of the influence of the underlying rock 



and Arborvitac on the distribution of vegetation, the author 



proceeds to show the importance of this factor 



in explaining the "anomalous" distribution of Thuja occidcntalis and 



the "irregularities" and "inconsistencies" in the distribution of Pinus 



banksiana The author explains these peculiarities of distribution in 



two generalizations according to the chemical nature of the soil, whether 



acid or basic. 



1. Pinus banksiana is confined to acid soils. 



2. Thuja occidcntalis is confined mainly to basic soils reaching its 

 maximum development and all of its outlying stations only in positively 

 calcareous areas. 



The greater part of the paper is devoted to a discussion of the 

 detailed ranges of the two species and the citation of a copious list of 

 references on the subject. Although Pinus banksiana, like other pro- 

 nounced oxylophytes, is practically eliminated from the vast limestone 

 region to the south and southwest of Hudson Bay, it is frequently 

 found on ridges of acid gravels and sands and it is also sometimes 

 found in acid bogs. The author states that Thuja occidentalis is al- 

 most as decidedly calcicolous as Pinus banksiana is calciphobous. Of 

 the differences of the soil which give special character to the vegeta- 

 tion the presence or absence of lime is regarded as the most important 

 feature in which petrology affects the distribution of plants. The simple 

 grouping of the calcareous and non-calcareous soil-forming rocks helps 

 to emphasize this feature of phytogeology. 



Those who do not consider calcareous soils important factors in limit- 

 ing forest distribution can profit materially by a perusal of this paper. 



C. F. K. 



Fernald, M. L. IJthologicol Factors Limiting the Ranges of Pinus Banksiann 

 and Thuja occidcntalis. Rhodora, 21 :41-67, March, 1919. 



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