10 RURAL MICHIGAN 



ing temperature, find the colder air flowing away 

 into the valleys and bottom-lands, thus affording a 

 fair margin of safety on the high lands. It has been 

 noted, for example, that the high ground of the 

 Paynesville "Quadrangle," in southern Ontonagon 

 County, Upper Peninsula, with an elevation of some 

 450 feet above Lake Superior, escaped killing frosts, 

 when neighboring farms on low-lying lands suffered 

 materially. When it is recalled that there is very 

 little flat country in Michigan, that much of its 

 land surface is undulating, billowy, of a knob and 

 depression, sag and swell description, it is evident 

 that, from this factor alone, agriculture is conducted 

 in varying conditions. It gives the mint and celery 

 country of the southwestern counties of the Lower 

 Peninsula and, at present in its incipiency, of the 

 eastern counties of the Upper Peninsula; and pro- 

 ductive fruit orchards at many interior points. It 

 affords numerous areas whose valuable crops must 

 continue to be blueberries, cranberries and wild rice, 

 and, if the vision of Sydney Smith Boyce of Saginaw 

 comes true, the swamp milkweed, from which, it is 

 hoped, a very useful textile fiber may be produced.^ 



THE GREAT LAKES SYSTEM 



The four enormous lakes, which, with their con- 

 necting waters, give Michigan her unique position 



'On lopoo-raTiliical features, see Leverett: "The Surface 

 Geology of Michigan"; Leverett and Taylor: "The Pleisto- 

 cene of Indiana and Michigan"; Bull. 461 and 559, U. S. 

 Geol. Survev; "Results of Spirit-Ijeveling in Michigan"; 

 "Dictionary' of Altitudes." 



