duction of the main crops, or between trees and vines in 

 orchards and vineyards. 



Covert 



A place of concealment for an animal, e.g., a hedge row. 



Cover Type 



The present vegetation on an area, a community form- 

 ing the Cover at the present time. 



Cow Month 



The quantity of feed or forage required for the main- 

 tenance of a mature cow in good condition for 30 days. cf. 

 sheep month. 



Creche 



A group of young animals after leaving their nests. 



Creek 



A stream that is intermediate between a river and a 

 brook. 



Creep, Soil 



The slow, downward, mass movement of soil on a slope. 



Crepuscular Periods 



The periods of dusk before sunrise and after sunset, cf. 

 Auroral, Vesper al, Diurnal, Diel, Nocturnal. 



Cretaceous 



The most recent geological period of the Mesozoic era, 

 which began abont 135 million years ago and lasted for about 

 60 million years. 



Critical Factor 



See Limiting factor. 



Critical Slope 



See Angle of repose. 



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