Frequence 



See Frequency. 



Frequency 



The degree of uniformity with which individuals of a 

 species are distributed in an area, and more specifically in 

 a Stand, cf. Constancy. 



Frequency Class 



One of the small groups into which the Frequency indices 

 of the various species in a stand may be classified. 



Frequency Index 



The quantitative expression in percentage of Frequency, 

 e.g., a species occurring in 15 of 20 sample areas in a stand 

 has a frequency index of 75 per cent. 



Frequency, Law of 



The generalization which states that when Frequency 

 indices of species in a stand are classified into five main 

 classes a double peak occurs in homogeneous vegetation, i.e. 



Frigid Zone 



The portions of the earth north of the Arctic Circle and 

 south of the Antarctic Circle. Cf. Temperate zone. Tropics. 



Frigorideserta 



Tundra or cold arctic and alpine, open communities. 



Fringing Forest 



A strip or zone of forest along a stream bed. cf. Gallery 

 forest. 



Front 



The border of cold and warm air masses at the earth's 

 surface. 



Frost 



(1) The act or state of freezing, or injury to organisms 



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