thin, organic mineral horizons above gray, leached horizons 

 upon illuvial, dark brown horizons; developed under coni- 

 ferous or mixed forests or heath vegetation in cool-temperate, 

 moist climates. 



Podzolic 



Refers to soils that have part or all of the characteristics 

 of Podzol. 



Podzoiization 



The process by which soils are depleted of bases, becom- 

 ing more acid, and develop leached surface layers from which 

 clay is removed, cf. Laterization, Calcification, Solonization. 



Poikilotherm 



An animal that lacks capacity to control its body tempera- 

 ture which is approximately that of the environment, e. g., 

 a frog. 



Point-contact Method (Point-frame) 



A technique for determining the area of herbage cover by 

 listing the number of times that various species are touched 

 by the point of a rod or pin. Numerous contacts are used in 

 each Stand or Plot. 



Poisson Distribution 



See Normal dispersion. 



Polar Front 



The boundary between the cold air of a polar region and 

 the warmer air of lower latitudes, cf. Warm front. 



Polarity 



The property of an organism to respond differently in its 

 various ends or in contrasting parts of its body to stimuli. 



Polder 



An area of land reclaimed from the sea or from a lake by 

 dams or dikes, especially in Holland. 



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