The plant population of northern lower Michigan and its environment 
ROLAND M. HARPER 
(WITH THREE TEXT FIGURES) 
Introduction.—The northern third of the Lower Peninsula of 
Michigan, an area of about 11,000 square miles, seems to differ 
from all other parts of the United States sufficiently to be treated 
as a distinct geographical region. Its most striking characteristic 
is probably the prevailing sandiness of the soils. (In this particu- 
lar, as well as in the abundance of lakes, swamps and bogs, it 
reminds one strongly of Florida.) It differs further from the 
Upper Peninsula, the nearest land tothe northward, in being warmer 
and therefore in having less of the boreal conifer element in its 
forests, and from the territory adjoining it on the south in being 
colder and in having a somewhat different seasonal distribution of 
rainfall (as will be pointed out farther on) and more swamps. 
The southern boundary is very indefinite, but may be located 
arbitrarily for statistical purposes at the parallel of latitude 44° 15’, 
which crosses the state from near the mouth of the Manistee River 
to the mouth of Saginaw Bay, and passes through or near Manistee, 
Cadillac, and Tawas City. Only about one sixth of the area is 
under cultivation, so that there is no lack of vegetation to study. 
But as the lumbermen spoiled the looks of the country before 
there were many botanists in Michigan, and nearly all the plants 
happen to belong to widely distributed species, comparatively few 
botanical explorers have investigated this region. Aside from 
incidental references in Cowles’s well-known monograph on the 
dunes of Lake Michigan (1899), Beal’s Michigan Flora (1904), 
and a few local plant lists, the following seem to be about the only 
easily accessible papers on this region that a phytogeographer 
would need to consult. Some of them contain references to earlier 
literature of some importance.. The arrangement is chronological. 
V. M. Spalding. ‘‘The Plains” of Michigan. Am. Nat. 17: 249-259. 1883. 
C.S. Sargent. (Forests of) Michigan. Tenth Census U.S.9:550-554. 1884. 
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