658 Ecology 



plants, larger plants such as the willows could gain a foothold. Finally 

 a subclimax forest characterized by many species of trees, birds, and 

 mammals would result. This latter associes would endure until the trees 

 characteristic of the climax gradually moved in. 



BARE BOTTOM 

 PIONEER STAGE 



SUBMERGED 

 VEGETATION 



EMERGING 

 VEGETATION 



TEMPORARY 

 POND AND 

 PRAIRIE 



BEECH AND MAPLE 

 FOREST CLIMAX 



Fig. 213. — Pond succession from bare bottom stage to climax forest. (From Read- 

 ings in Ecology by R. Buchsbaum, copyright, 1937, by R. Buchsbaum.) 



A developmental sere such as this would take a varying amount of 

 time depending upon climatic conditions ; however, the observation may 

 be done in an afternoon by simply walking back from the lake toward the 

 forest. All developmental stages may be encountered in such a stroll. 



A sere culminating in the same climax community may also start 

 from bare ground. In the sand dunes of Lake Michigan, the pioneer 



