148 ARTHUR G. VESTAL. 



plants bordering lakes, streams, and certain open bogs are usually 

 composed of only one or a few plant species. These growths, 

 depending upon local conditions of moisture, are frequently 

 small in area, and different stations are not always alike. Condi- 

 tions of shade and of soil are variable. No grasshoppers were 

 found upon the marsh plants which grew standing in open water, 

 although in dense growths individuals sometimes stray beyond 

 the shore. The numbers of grasshoppers vary considerably 

 in different stations. They are most numerous in tall, rather 

 close, sedge or grass growths. Stenobothrus curtipennis is the 

 characteristic grasshopper of littoral situations. Melanoplus 

 atlanis, M. bivittatus, and M. differentialis are less frequently 

 found. M. femur-rubrum, though not taken by the writer, is 

 often found in such places. The Melanopli are more numerous 

 in the higher and more open parts, while Stenobothrus occurs 

 farthest out towards the water. 



Ruderal Associations. 



In the Douglas Lake region much of the native forest has been 

 removed by cutting and burning, and its place has been taken 

 by cultivated crops and weed growths. In addition many plant 

 associations, though not destroyed, have been materially changed, 

 and native animals have also been much affected. Secondary 

 successions are principally due to interference by man. Most of 

 the sandy land is now occupied by aspens as a result of destruction 

 of the pines. One of the most important plants favored by 

 artificial conditions is the blue-grass, Poa pratensis, which enters 

 into nearly all ruderal growths. Other species of Poa probably 

 occur in the region. 



Ruderal Dry Grassland Associations. Abandoned fields, dry 

 pastures, roadside growths, and modified aspen undergrowth are 

 the common forms of ruderal growth in dry situations. They 

 are necessarily very different in physical conditions and plant 

 composition, depending upon differences in original status and 

 subsequent modification. In certain large areas west of Douglas 

 Lake, near Pellston, a growth of bluegrass has almost entirely 

 replaced the aspen association. Near the lake bluegrass invades 

 the aspens along roadways, and one can trace long abandoned 

 roads by the presence of this plant. Other weed species are 



