Growing Stock 



The total number or total volume of all the trees in an 

 area. 



Growth Form 



The characteristic shape or appearance of an organism 

 as a result of its development in response to the impinging 

 environmental conditions within its genetic constitution, cf. 

 Habitat form, Phenotype, Genotype. 



Growth Layer 



A layer of Xylem and Phloem produced in woody stems 

 usually during each growing season, cf. Annual ring. 



Growth Ring 



A Growth layer seen in the cross section of a woody stem. 



Growth Substance 



Any chemical produced by a plant, or synthetically, that 

 regulates plant growth, cf. Hormone. 



Gully 



A channel or small valley formed by running water which 

 usually flows only during and immediately after heavy rains 

 or the melting of snow; it may be branched or linear and 

 fairly long, narrow, and uniform in width; smaller than a 

 ravine, deeper than a rill. 



Gully Erosion 



Removal of stones, gravel, and finer material by running 

 water with the formation of channels that cannot be smoothed 

 out completely by ordinary cultivation. 



Guttation 



The exudation of water in liquid form from plants 

 through HydathodeSj (q. v.). cf. Transpiration. 



Gymnosperm 



A plant in the class Gymnospermae of the seed plants, 

 Spermatophytes, in which the seeds are not enclosed within 

 an ovary, e.g., pine, spruce, cf. Angiosperm. 



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