amount held at Field capacity (q. v.) and the amount at the 

 Permanent Wilting percentage (q. v.). 



Avalanche Cone 



Materials such as rocks, snow, ice, trees, deposited at the 

 base of the path of an avalanche. 



Avalanche Wind 



A wind, often destructive over a distance, produced by 

 an avalanche. 



Average Distance 



The distance between plants determined by dividing the 

 square root of an area by the density of each species within 

 the area. 



Avitaminosis 



An unhealthy condition or disease caused by a deficiency 

 of vitamins. 



Awn 



A bristle-like structure attached to plant parts such as on 

 Floret parts of grasses. 



Azonal (soil) 



A soil without a well-developed profile, occurring in any 

 soil zone, consisting largely of Parent material (q. v.), e.g., 

 recently deposited Alluvium, dune sand. 



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