Crown Canopy 



See Crown cover. 



Crown Class 



The trees occupying a similar layer or position in the 

 crown cover such as the dominant crown class consisting of 

 dominant trees in the canopy layer; co-dominant crown class, 

 trees with less well developed crowns but in the canopy 

 layer; intermediate crown class, trees with crowns mostly 

 below the canopy layer but extending into it; and overtopped 

 crown class, trees with crowns entirely below the canopy 

 layer, crowns poorly developed, or trees are suppressed, dying, 

 or dead. 



Crown Cover 



The canopy formed by the trees in a forest. 



Crown Density 



The percentage of the total area of land that has a com- 

 plete crown cover. 



Crucifer 



A plant in the mustard family, Cruciferae, e. g., radish. 



Cruise 



A survey of forest land to locate and estimate the volume 

 and grades of the standing timber; or an estimate secured 

 in such a survey. 



Crumb Structure 



The condition of a soil that contains irregularly shaped 

 and highly porous aggregates. 



Crustacean 



An Arthropod in the class Crustacea, e. g., crab, shrimp. 



Crustal Movement 



A movement of the outer solid part of the earth such as 

 an earthquake. 



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