THE DEVELOPMENT OF CLIMAX FORMATIONS IN 

 NORTHERN. MINNESOTA 



H. F. Bergman and Harvey Stallard 



The climax vegetation of a region is the result of all the forces 

 operative upon it during its development, its general features being 

 determined by the climate. Within a region the same final or climax 

 stage results through a series of developmental or successional 

 stages, whether starting from open water, solid rock, or denuded 

 land. 



It is the purpose of this paper to trace the successions from the 

 initial to the climax stage in northern Minnesota, as well as the 

 forces that have operated together to produce the climax or earlier 

 stages of stabilization. These processes may be expected to con- 

 tinue without change, unless disturbed by a reversal of climatic 

 conditions or by any other change which would seriously afifect the 

 water or light relations of the dominants in the climax. 



The results here presented are based upon field work which has 

 extended over a period of four years and has involved the study of 

 coniferous and deciduous forest, swamp, and other developmental 

 stages in different parts of the state. The work has been of an 

 exact nature, with quadrats and instruments, so that definite infor- 

 mation has been obtained as to the structure of vegetation of the 

 climax stages and of the successional stages leading up to the cli- 

 max, as well as of the factors concerned in the development. 



The work was undertaken at the suggestion and under the di- 

 rection of Dr. Frederic E. Clements, to whom the writers are in- 

 debted for invaluable suggestions and criticisms, and particularly 

 for his kindness in placing freely at their disposal his work on 

 Plant Succession, which has been used in the preparation of this 

 report. The classification of successions and of the causes initiating 



