GRASSHOPPERS IN RELATION TO PLANT ASSOCIATIONS. 143 



and in several places lagoons. Wave action is considerable on 

 exposed parts of the shore-line, but the exposed sand has been 

 very little acted upon by wind. Beach dunes occur sparingly 

 and are of small area. 



General Character of the Vegetation. 



Much of this part of Michigan is covered with two general 

 types of vegetation, which give rise to the common terms "pine 

 lands" and "hardwood lands." The pine forests have been 

 developed on the more sandy areas, the hardwoods on the loamy 

 or clay moraines. "Hardwood lands" are of much greater 

 agricultural value, and the more extensive farming districts are 

 in morainic regions. The pine lands have been largely def crested , 

 and fire has also been very prevalent, so that many of the original 

 pine forests have been replaced by growths of the large-toothed 

 aspen. In the immediate region of the biological station virtually 

 no pine forest remains, though scattering growths of pitch pine 

 are not rare along the beach, and a few pines are to be found 

 scattered among the aspens. The aspen forest occupies more 

 than one half of the entire area studied; the hardwood forest 

 and hardwood clearings somewhat more than a fourth of the 

 area, and other kinds of vegetation considerably less than one 

 fourth. These other kinds of vegetation are grassland areas, 

 cultivated fields, meadows and sedge growths, cedar bogs, and 

 open peat bogs. The plant associations have been studied in 

 detail by Gates ('13), with reference to a much larger area than 

 has been covered in the present study. 



II. THE PLANT ASSOCIATIONS AND THE GRASSHOPPERS WHICH 



OCCUR WITHIN THEM. 



Associations of two vegetation regions or vegetation provinces 

 (Gleason, '10: 42-45) occur within the area. The coniferous 

 forests, the aspen forests, heaths and bogs of the region, typical 

 of the northeastern states and much of Canada, represent the 

 Northeastern Conifer Province. The deciduous forest (hard- 

 woods) and the herbaceous and thicket growths of hardwood 

 clearings represent the Eastern Deciduous Forest Province. 

 While primarily consisting of these two geographic elements, the 

 vegetation also includes local associations, particularly those 



