﻿THE DISTRIBUTION OF THE UPLAND PLANT SOCI- 

 ETIES OF KENT COUNTY, MICHIGAN/ ■ 



CONTRIBUTIONS FROM THE HULL BOTANICAL LABORATORY. 



■ XLIII. 



■ » 



Burton Edward Livingston. 



r 



(with map) 

 introduction. 



I. Climatology of the county. — Kent county is so situ- 

 ated that it is traversed both by the southern boundary of the | 

 pine-forest region and the eastern boundary of the so-called 

 Michigan peach belt. It is also crossed by the Grand River val- 



r 



ley, the line of one of the great main channels by which the^ 

 melting ice of the glacial period reached the Mississippi system 

 and the Gulf, and also the line marking the farthest northern 

 extension within the peninsula of many typically sou thern plants. 

 The county embraces a rectangular tract of land 38.6*'"' by 

 57.9^°^ in extent. Its western boundary is a meridian averag- 

 ing about 37^"" east of Lake Michigan at its widest part. 

 Lacustrian influence upon the climate is probably felt through- 

 out the county. Owing to the comparatively small extent of 

 area, differences in climate between its different parts could 

 hardly be pronounced enough to cause any marked difference in 

 its vegetation. Also on account of the great distance apart of 

 the stations for meteorological observations, if there were less 



differences between the climates of different portions of the 

 county, such would not be brought out by any records which 

 have been made. Therefore, a study of tHese meteorological 

 data can hardly give any clue to the principles underlying plant 

 distribution within the area.^ 



*A less technical account of the survey here presented was published in the 

 Annual Report of the State Board of Geological Surv^ey of Michigan, 1901, pp- 

 81-103, and it is through the courtesy of Dr. A. C. Lane, state geologist, under whose 

 auspices the work was done, that the present account is published. 



* Tables of the average temperature and precipitation by months for this region, 

 compiled from the reports of tiie Michigan section of the U. S. climate and crop 

 service, are to be found in the author's former publication, loc. cit. 



36 [JANUARY 



