Minnesota Geological Survey LIBRARY m~r Uuiurrliity nf .itiuurlintu MINNESOTA GEOLOGICAL SURVEY WILLIAM H. EMMONS, DIRECTOR IN COOP. ATION WITH THE UNITED STATES GEOLOGICAL SURVEY BULLETIN NO. 14 SURFACE FORMATIONS AND AGRICULTURAL CONDITIONS OF THE SOUTH HALF OF MINNESOTA BY FRANK LEVERETT AND FREDERICK W. SARDESON WITH A CHAPTER ON CLIMATiC CONDITIONS IN MINNESOTA BY U. G. PURSSELL Minnesota Geological Sumy LIBRARY MINNEAPOLIS The University of Minnesota CONTENTS Introduction .............................................. 1-4 Chapter 1. Physical features of Minnesota .................... 5-22 Topography of Minnesota ............................. 5-9 General statement ................................. 5 Altitude ......................................... 6 Relief ............................................ 6 Drainage ......... , " ............................ 6 Lakes .................................... -........ 7 Surface geology ...................................... 10-IS Rock areas ....................................... 10 The earthy mantle .............................. 10 General statement .............................. 10 Residuary material ........................... II Wind deposits ................................ II Glacial deposits .............................. II Stream deposits ............................... 14 Lake deposits ................................ 14 The glacial features and their history ................. 14 Glacial lake features .............................. 16 General soil conditions .................................. IS-22 Vegetation ., ..................................... 19 Weathering _...................................... 19 Lime ............................................ 21 Effect of fires ..................................... 21 Chapter II. Climatic conditions ............................. 23-44 Introduction ......................................... 23- 2 4 General climatic conditions .............................. 24-44 Temperature ..................................... 24 Frosts .......................................... 31 Precipitation ...................................... 36 Snowfall .......... , ............................. 40 Winds ........................................... 40 Relative humidity ................................ 41 Number of rainy days ............... '" ...... '" ... 41 Sunshine ........................................ 41 Chapter III. Agricultural conditions and land classification in the south half of Minnesota ........................ '" ........ 45-62 General statement ..................................... 45 Driftless area ........................................ 45-46 Loess-covered pre-Wisconsin drift ....................... 46-47 iv CONTENTS Old gray drift (Kansan) with little or no loess cover ....... 47 Iowan drift over Kansan drift ......................... 47-48 Old red drift (Illinoian) over old gray drift (Kansan) .... 48-49 Young or Wisconsin red drift (Patrician ice sheet) ....... 49-50 Young or Wisconsin red drift (Labradorian ice sheet) ..... 50 Border of young gray drift (Keewatin ice sheet) in central Minnesota .......................................... 50-51 Border of young gray drift in southwestern Minnesota ..... 51-52 Moraines of southwestern Minnesota .................... 52-53 Moraines of southeastern Minnesota ..................... 53 Overlap of red drift by gray drift in Grantsburg lobe ....... 53-54 Gray drift moraines of central Minnesota ................ 54-55 The great plain of the Minnesota lobe .................... 55-56 The great Red River plain .............................. 56-57 The Lake Agassiz area ................................. 57 Outwash sand and gravel plains ........................ 57-58 Alluvial bottoms ...................................... 58 Farming development in Minnesota ..................... 58-60 Rank of different crops in Minnesota .................... 60-62 Relation of crop values to farm investments in southern Min- nesota .............................•........•........ 62 Chapter IV. Descriptions of counties ....................... 63- 142 Pine County ......................................... 63-64 Southern Aitkin County ............................... 64-65 Kanabec County ..................................... 65-66 Mille Lacs County ...................................... 66-67 Southern Crow Wing County .......................... 67-68 Southern Cass County .................................. 68 Morrison County ..................................... 68-70 Todd County ........................................ 70-71 Southern Otter Tail County ............................. 71-72 Douglas County ...................................... 72 -73 Grant County ......................................... 73-74 Wilkin County ....................................... 74-75 Traverse County .......................... '" ......... 75-77 Big Stone County .................................... 77-78 Stevens County ...................................... 78-79 Pope County ......................................... 79-81 Stearns County ...................................... 81-82 Benton County ........................................ 82-83 Sherburne County .................................... 84-85 Isanti County ........................................ 85-86 CONTENTS v Anoka County ........................................ 86-87 Chisago County ...................................... 87-88 Washington County .................................. 88-89 Ramsey County ...................................... 89-90 Hennepin County .................................... 91-92 Wright County ................... , ................... 92 -93 Meeker County ....................................... 93-94 Kandiyohi County .................................... 95-96 Swift County ••........................................ ¢-97 Chippewa County .................................... 97 Lac qui Parle County .•................................. 98 Yellow Medicine County ............................... 99 Renville County ....................................... 100 McLeod County ..................................... lor Sibley County ........................................ 101-2 Carver County ....................................... 102-3 Scott County .......................................... 103-4 Dakota County ...................................... 104-6 Goodhue County ..................................... 106-9 Rice County .......................................... 109-II Le Sueur County ..................................... 1II-12 Nicollet County ....................................... II2-13 Brown County ....................................... 113-14 Redwood County ...................................... II4-1 5 Lyon County ......................................... II 5-16 Lincoln County ....................................... 116-1 7 Pipestone County ..................................... 117-19 Murray County ....................................... II 9-20 Cottonwood County .................................. 120-21 Watonwan County ..................................... 121-22 Blue Earth County .................................... 122-2 4 Waseca County ....................................... 124-2 5 Steele County ........................................ 125-26 Dodge County ........................................ 126-2 7 Olmsted County ..................................... 127-28 Wabasha County .... , ................................. 128-2 9 Winona County ...................................... 129-31 Houston County ...................................... 13 1-32 Fillmore County ...................................... 132 -33 Mower County ........................................ 133-35 Freeborn County ..................................... 135-36 Faribault County ...................................... 136-37 vi CONTENTS Martin County ........... , ............................ 137-38 Jackson County ........................................ 138-39 Nobles County ........................................ 139-41 Rock County ..................... .................... 141-42 LIST OF ILLUSTRATIONS Plate I. Map of the surface formations of Minnesota ..... in pocket II. A. Bed of Lake Agassiz near Wheaton B. Grain field in bed of Lake Agassiz near Wheaton C. Gray drift till plain in Chisago County. 58 III. A. Cultivated red drift till plain near Foley B. Red drift till plain with forest near Foley C. Boulders on red drift till plain near Foley. 62 IV. A. Gray drift moraine north of St. Paul B. Red drift moraine with coating of gray drift north of St. PauL....................... 90 V. A. Wisconsin, or young red drift, moraine near Stillwater B. Old red drift moraine near Hampton. 92 VI. A. Outwash plain east of Anoka B. Outwash plain of gray drift west of White Bear C. Outwash plain with thick clayey covering north of St. PauL............................. 94 VII. A. Slope of the Coteau des Prairies near Canby. Gray drift moraine B. Eroded upland in old gray (Kansan) drift north­ east of Zumbrota C. Broad valley cut in old gray (Kansan) drift west of Kenyon.......................... 108 VIII. A. Loess-covered driftiess area near Caledonia B. Valleys bordered by limestone tablelands near Hampton ............................... 132 IX. A. Zumbro valley near Rochester B. Valley of Rollingstone River near Minnesota City C. Mississippi valley at Minnesota City. 140 viii LIST OF ILLUSTRATIONS TEXT FIGURES Fig. 1. Altitude map of Minnesota.. 8 2. Map of glacial drifts, loess, and glacial