14 STATE HORTICULTURAL SOCIETY. 



them in their natural societies, each of which would have told observ- 

 ing and well-informed \settlers much valuable truth about the soils in 

 which their roots were anchored. For, just as the native plants require 

 certain soil environments for their best development, so do cultivated 

 plants require soils selected to suit their particular luibits in order 

 that they may be groAvn profitably. 



Thousands of years ago a great ice sheet that had accumulated on 

 the northern regions of the earth, moved slovrly soutliward, probably 

 puslied forward by the weight of its own accumulation in the far north. 

 The causes that operated to bring about this gigantic movement are 

 not entirely clear, but that such a movement actuall}- occurred is proven 

 beyond question by the trail left when the ice front gradually melted 

 away and receded again to the polar regions where, today, observers 

 find exactly such eftects being i)roduced by glacial ice as are evident 

 in our locality and extending several hundred miles farther to the south. 



Where we are today this ice sheet was i)ossibly one thousand feet 

 deep. It gouged its way through the rocks to a depth, at this place, 

 of about 225 feet below ])resent lake level, where we now find the bed 

 rock that bears the scratches and grooves made by the slowly moving 

 mass. When the ice melted away, great bodies of crushed or pulverized 

 rock, boulders and gravel Avere rek'ased and deposited in various ways. 

 Much of this was left in the form of ridges and peaks called mora hies 

 by the geologists. Other materials were caught by the floods that con- 

 tinued, probably for centuries, rushing from the front of the melting 

 ice and were thus spread out into more or less extensive plains. 



As everybody knows, a current of water carrying susi)ended matter 

 drops the coarser and heavier ])articles first as the speed slows down. 

 It so hax>pened that the glacial streams dropped a large amount of 

 coarse sand within the present boundaries of Muskegon county while 

 much of tlie finer and better soil-making materials were carried farther 

 and de])Osited elsewhere. This fact has made the problem of the sand 

 soils of Muskegon count}' as it has also in other parts of Micliigan. 



The larger jtortion of this county is covered by a sand sheet that dips 

 practically to the level of Lake Michigan at Little Black Lake near the 

 extreme southwest comer of the county. From this point the surface 

 rises gradually in all directions from eastward to northward, being 50 

 feet above lake at Muskegon, due north, about 100 feet at Moorland 

 and 110 feet at Twin Lake. This gives an average gradient of between 

 6 to 8 feet per mile and suggests an interesting speculation as to the 

 origin of this particular plain, which will be followed out somewhat 

 in detail. 



Along the borders of the county on the north and east most of the 

 surface is undulating and liilly Avhere the ice left great ridges and 

 mounds of clay, loam and gravel. Nearly the entire surface of C'asnovia 

 township is of this character. At Casnovia village is the highest rail- 

 road station in the county, the Pere Marquette track there being 303 

 feet above mean lake level. Some of the surrounding hill summits ex- 

 ceed this height by about 100 feet. 



Returning to the original sand plain and following it inland along 

 Muskegon River from the lake to the county line we would find our- 



