FIG. 8-11 Stages in the strip-mine 

 plant sere in east central Illinois, 

 (a) sweet clover, aster, ragweed, 

 after 7 years, (b) same area 10 years 

 later, trees invading, (c) silver 

 maple-cottonwood-sycamore flood plair 

 forest after about 40 years (Wetiel 

 1958). 



perennial grasses ; mixed herbaceous perennials ; 

 shrubs ; and finally three tree stages, the first reached 

 in 21 to 25 years. Prairie deer mice are at their most 

 abundance during the early stages, meadow voles in 

 the intermediate grassy stages, and the woodland 

 white-footed mouse and short-tailed shrew in the 

 shrub and tree stages. Such game species as ring- 

 necked pheasants, bobwhite, and cottontail rabbits 

 are common on abandoned farmlands but give way to 

 another group of game species, including white-tailed 

 deer, ruffed grouse, and gray squirrels, when the 

 forest stages become established (Beckwith 1954). 



Pastures 



Pastures in northern Ohio contain a sod prin- 

 cipally of blue grass. With light grazing, this sod 

 will resist invasion of other species for a long time, 

 but with heavy grazing, resistance is weakened and 

 unpalatable herbs, briars, and hawthorne come in. 

 The latter two species are armed with prickles or 

 thorns discouraging animal browsing. When they be- 

 come dense enough they kill the grass beneath them. 

 Eastern redcedar may establish itself in horse pas- 

 tures, but not in cattle pastures ; cattle browse it but 



116 Habitats, communities, succession 



