In summary, the criteria to differentiate a climax community 

 from a successional community are subjective and relative. Tfie 

 climax community is in the steady-state with respect to produc- 

 tivity, structure, and population (Figure 5-10). There is a diver- 

 sity, stability, and homogeneity of the species populations within 

 and between stands of the same climax community. Each stand 

 is self-maintaining and long-persisting. Replacement and fluctua- 

 tion changes are operative on a continuing basis within the 

 climax, while all environmental factors determine its composition 

 and population so that there is a mosaic of climax types corre- 

 sponding to the mosaic of habitats. 



Conclusions 



One of the more important and difficult tasks of the ecologist 

 is to determine the dynamics within and between communities 

 and especially the successional or climax status of each commu- 

 nity. Five kinds of significant change are: replacement, inter- 

 community cycle, directional and fluctuation changes in the 

 same place, and change in space. Succession is one type of change 

 — a very important kind. The analysis of changes provides a 



Figure 5-10. A climax forest 

 of virgin hemlock {Tsuga 

 canadensis), with aggrega- 

 tions of the broadleaf ever- 

 green, Rhododendron maxi- 

 mum, in the shrub layer. 

 May, Clarion County, Penn- 

 sylvania. (U. S. Forest 

 Service.) 



