﻿NOTES ON SUCCESSION FROM PINE TO OAK 



Recent developments in the study of vegetative succession have 

 changed ideas about the factors causing pine forests and oak 

 forests. Formerly, even after the advent of the dynamic point of 

 view, pine was supposed to grow only on sandy soils and oak only 

 on soils containing clay. Now there is a strong tendency to con- 

 sider pine as merely an earlier stage in the evolution from simpler 

 associations to the climatic climax of the region, though the effect 

 of the soil in hastening the process of evolution is recognized. The 

 work in the region of the Great Lakes, particularly south of Lake 

 Michigan, 1 has done much to bring this about. The ideas developed 

 by these and other workers are widely disseminated through the 

 literature dealing with vegetation and environment. But Taylor 2 

 has lately found, on the strength of geological facts which geologists 

 admit are incontrovertible, and of phytogeographic evidence which 

 appears at least convincing, that the pine barrens of New Jersey 

 are not a new, but a very ancient, vegetation. 



The attitude toward pine forests, therefore, may have to undergo 

 revision. This does not mean necessarily that the work of Cowles 

 and his associates is in error, but that possibly their conclusions 

 have been too widely applied. It must be remembered that our 

 knowledge of the factors which influence plants, especially of the 



I vicinity; a study in 



, The causes of vegetative cycles. Bot. Gaz. 51:161-183. 191 1. 



Whitford, H. N., Genetic development of the forests of northern Mic 

 a study in physiographic ecology. Bot. Gaz. 31 : 280-325. 1901. 



, Evaporation and soil moisture in relation to the succession of plant a; 



tions. Bot. Gaz. 58:193-233. 1914. 



Livingston, B. E., The relation of soils to natural vegetation in Roscommc 

 Crawford counties, Michigan. Bot. Gaz. 39:22-41. 1905- 



2 Taylor, Norman, Flora of the vicinity of New York. Mem. N.Y. Bot. G 

 5: 19 15, especially pp. 8-25. 



59] (Botanical Gazette, v 



