Classification Units 



Region 



Province 



Zones 



Series 



Habitat Types 



Phase 



Description 



Regions have a high degree of physiognomic uniformity 

 among the climatic climaxes, and a gross similarity of 

 climates throughout However, taxonomic similarity is not a 

 requirement. 



Provinces arc zones in which the dominants of the climatic 

 climaxes have had much the same geologic history, exhibit a 

 strong thread of taxonomic continuity, and occur in climates 

 of somewhat similar pattern. A finer subdivision of a 

 province is a section. 



Zones are the entire area over which zonal soils support what 

 may be considered the same type of climatic climax. Zones 

 are areas of essentially homogeneous macroclimate as 

 indicated by a coimnon climatic climax. The zones iit 

 together on a map as a mosaic without overlap, although the 

 plant association that is climatic climax in one zone usually 

 occurs as an edaphic or topographic climax in a contiguous 

 zone, where it becomes restricted to an environment which 

 compensates for the relatively unfavorable macroclimate. 



A series is a group of habitat types having the same potential 

 climax overstory. 



A habitat type is all the area of land capable of supporting 

 the same climax plant association whether this be climatic, 

 edaphic, or topographic climax. (A plant association is a 

 kind of plant community represented by stands occurring in 

 places where environments are so closely similar that there is 

 a high degree of floristic uniformity in all layers.) 



A phase is a subdivision of a habitat type representing a 

 characteristic variation in climax vegetation and environ- 

 mental conditions. 



Riparian 

 Association 



Additional Ecological Terms 



A riparian association is a plant community type represent- 

 ing the latest successional stage attainable on a specific 

 hydrologically influenced surface (equal to potential natural 

 community). Because the riparian association is the end 

 result of plant succession, it reflects the most meaningful 

 integration of environmental factors affecting vegetation. 

 [Because of the difficulties of defining climax in the classi- 

 cal sense for flood plain environments, this system currently 

 follows the lead of Kovalchik (1987) in using the term 

 riparian association to represent the latest successional stage 

 available.] 



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