MOIST FOREST MARGIN 263 



2. FIELD AND SHRUB STRATA 



Here two zones may be recognized. While there is no reason for 

 separating them in the ground stratum, a rough separation is here 

 possible. 



a) Rank weeds, willow, dogwood, grape, etc. 



b) Prickly ash thicket with grape and young elms. 



Outside the first is a girdle of low prairie from which low prairie plants 

 and some low prairie animals occasionally invade the forest margin. 



a) Girdle of rank weeds, dogwood, willow, etc. — In open, grassy places 

 the garden spiders (Argiope aurantia and trifasciata) (Fig. 255) fasten 



Fig. 254. — Low forest margin at Wolf Lake, Ind. In front of a, low prairie 

 area; opposite b, belt of rank weeds: opposite c,Jow shrubs; opposite d , high shrubs; 

 opposite e, trees. 



their webs to any firm support, such as a young shrub. Various grass- 

 hoppers occur in open situations (Xiphidium fasciatum and brevipenne 

 belong more properly to low prairie) (Fig. 256). The long-bodied spider 

 (Tetragnatha labor iosa) (138) is a common resident. On the grasses 

 beneath the shrubs the black-sided grasshopper {Xiphidium nigropleura) 

 is abundant. The snail (Fig. 257) (Succinea ovalis) is sometimes 

 common. 



Of the bugs which frequent the blossoms of the coarse weeds are the 

 long-legged bug (Neides muticus), the buffalo tree-hopper (Fig. 259), and 

 the candlehead (Scolops sulcipes) (Fig. 258). These two and especially 

 the latter, with its curiously prolonged prothorax, are the most char- 

 acteristic. The common plant-bug (Lygus pratensis) (Fig. 261) and an 



