224 



TYPICAL EXAMPLES OF PLANT SUCCESSION 



trifida) are present also. On the other hand, some of the deeper 

 furrows, which lack adequate drainage, have water standing in them 

 a greater part of the time. Here are found cat-tails (Typha latifolia) 

 and occasionally water plantain (Plantago alisma-aquatica) . Just 

 above the water there is usually a zone of cocklebur (Xanthium 

 commune) . 



The ridges present somewhat more variety in their floras, although 

 some of them are occupied almost exclusively by sweet clover 

 (Melilotus alba) which grows 7 feet high and so thick that it is difficult 



Fig. 100.— Creating a bare area. Striplands, Vermilion County, Illinois. 



to walk through. Other ridges are covered with such plants as wild 

 aster (Aster ericoides), sunflowers (Helianihus hirsutus and H. de- 

 cayetahis), ragweed {Ambrosia artemisiifolia), evening primrose 

 {(Enothera biennis), black mustard {Brassica nigra), and prickly 

 lettuce (Lactiica scariola). 



The first woody plants are usually willow (Salix nigra) and cotton- 

 wood, but this depends upon the proximity of communities from 

 which these plants may migrate, and sometimes the buttonbush 

 (Cephalanthus occidentalis) and the soft maple (Acer saccliarinum) , 

 the white elm (JJlmus americana), the green ash (Fraxinus lanceo- 

 lata), and the sycamore (Platamis occidentalis) come in almost as 

 soon as the typically hydric pioneers (Fig. 101). In any case they 

 are sure to come sooner or later and are likely to be accompanied by 

 honey locust (Gleditsia triacanthos) and such lianas as wild grape 

 (Vitis cordifolia) and poison ivy (Rhus toxicodendron). The elm, 

 sycamore, and honey locust are commonly the dominant species of 

 the bottomland forest in this region and such a forest may become 



