VEGETATION REGIONS xix 



and Minneapolis, and west nearly to the Red River valley. These 

 evergreen forests are continuous with those of Ontario on the north- 

 east, and with those of northern Wisconsin and upper Michigan on 

 the east. The characteristic trees of this region are the three native 

 pines, white spruce and balsam fir in mature upland forests, black 

 spruce, tamarack and white cedar in the swamps. Throughout this 

 region deciduous trees are either minor or temporary factors in the 

 vegetation. Thus although the hard maple, basswood, red oak and 

 white elm occur throughout the regions they do not occupy such great 

 areas as they hold farther south, and the abundant growth of aspen, 

 balsam, poplars and birches which usually follows the destruction of 

 the conifers by cutting or burning, is itself followed by evergreens, 

 if not further disturbed. 



The shrubs as well as the trees of the evergreen forests are, many 

 of them, characteristic. Here are found the white-flowered thimble- 

 berry, the mountain maple, dwarf birches, alders, sweet-fern, several 

 kinds of bush honeysuckle, high-bush cranberry, and, most character- 

 istic of all, numerous heaths, such as trailing arbutus, wintergreen, 

 dwarf Kalmia, the numerous blueberries and huckleberries. 



The deciduous forest occupied a strip extending across the state 

 from southeast to northwest and forming an almost complete barrier 

 between the evergreen forests and the prairies. Throughout this 

 region the number of species of trees diminishes steadily from south- 

 east to northwest. The most characteristic trees on heavy rich subsoil 

 are hard maple, basswood, elm and red oak. The finest strip of hard- 

 wood timber in the state, known to the early settlers as the "Big 

 Woods," consists very largely of these trees. Lying about fifteen 

 miles west of Minneapolis, it originally extended about fifty miles 

 east and west and nearly a hundred north and south. In the south- 

 eastern corner of the state, the dominant trees are black oak, black 

 walnut, and shellbark hickory in addition to those species which occur 

 farther north. Throughout the southern half of the state, somewhat 

 sour clay subsoils are apt to be covered with a nearly pure growth 

 of white oak. On drier and less fertile subsoils are usually open for- 

 ests of bur oak, scarlet oak and northern pin oak, which pass into 

 mere thickets where the soil is very light and porous. 



Throughout this region of deciduous forest, there are almost 

 none of the conifers which are so abundant in the northeastern part 

 of the state. The tamarack alone occurs to any extent. It occupies 

 many bogs and swamps as far south as the Minnesota river. These 

 tamarack swamps are, as it were, little pieces of the northern forest 



