STANDARD CROWN CLASSES 



155 



Standard Crown Classes 



Dominant. Trees with crowns extending above the gen- 

 eral level of the forest canopy and receiving full light from 

 above and partly from the side; larger than the average trees 



D = Dominant trees. C-D = Co-Dominant trees. I = Intermediate trees. 

 Op = Oppressed trees. S = Suppressed trees. 



FIG. 58. 

 Illustrates the relative position of trees of the different crown classes. 



60 



a w 



20 



10 



D\/D\/D\/D\/D\/D 



FIG, 59. 



Illustrates the passing of trees from the dominant down to the suppressed 

 crown class with advancing age, as a result of the struggle for existence. The 

 letters indicate the crown classes of the trees. 



