under specified conditions, issued to a livestock operator by 

 the agency in charge of the lands. 



Grazing Preference 



The criteria used in the administration of public grazing 

 lands for the issuance of grazing permits and licenses. 



Grazing Unit 



A division of the Range for the facilitation of adminis- 

 tration or the handling of livestock. 



Green Manure Crop 



A crop grown for the purpose of turning under while 

 it is still green, or shortly after maturity, in order to improve 

 the soil. 



Gregariousness 



The tendency of organisms to congregate or form groups, 

 e.g., reindeer, cattails. See Sociability. 



Grinnell's Axiom 



The generalization stating that no two species in the same 

 general territory can occupy for a long time the same 

 ecologic Niche, cf. Cause's principle. 



Ground Cover 



See Cover. 



Ground Water 



Water standing in or moving through the soil and under- 

 lying strata, Gravitational water, the source of water in 

 springs and wells, cf. Runoff. 



Group Control 



The control or influence of the behaviour of a group of 

 animals, by means of the cue behaviour or a signal of specific 

 animals. 



Growing Point 



One of the sections of a plant body in which growth is 

 localized, especially the tips of stems and roots. 



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