AMERICAN SYLVICULTURE 



C. According to the degree in wMcli the soil and the 

 youngest seedlings are directly exposed to the sky: 



I. Regeneration without exposure, — by advance growth. 



II. Regeneration with short, slight, partial exposure, — under 

 shelterwood. 



III. Regeneration with entire, heavy exposure, — from adjoining 

 timber. 



D. According to the timing of lumbering and of 

 reseeding: 



I. Lumbering precedes reseeding, — natural seed regeneration on 

 clearings, namely: 



a. On uniformly cleared compartments (cleared compartment 

 type) ; 



b. On cleared strips (cleared strip type); 



c. On cleared groups (cleared group type) ; 



d. On cleared selected patches (cleared selection type). 



II. Lumbering coincides with reseeding, — natural seed regenera- 

 tion under shelterwood, namely: 



a. On uniformly sheltered compartments (shelterwood compart- 

 ment type) ; 



b. On sheltered strips (shelterwood strip type) ; 



c. On sheltered groups (shelterwood group type); 



d. On sheltered selected patches (shelterwood selection type). 



III. Lumbering follows reseeding, — natural seed regeneration by 

 advance growth, namely: 



a. With advance growth all over a compartment (advance 

 growth compartment type) ; 



b. With advance growth in strips (advance growth strip type) ; 



c. With advance growth in groups (advance growth group type) ; 



d. With advance growth in selected patches (advance growth 

 selection type). 



E. According to the participation of ligneous -weeds 



(bushes, seedlings, saplings, poles and trees of a negative value) in 

 the regeneration: 



Totally successful seed regeneration; 



Groupwise successful seed regeneration; 



Patchwise successful seed regeneration; 



Individually successful seed regeneration; 



Unsuccessful seed regeneration. 



In America, it will be frequently advisable for the forester to 



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