SYLVICULTURE 



C. Advantages: 



I. The water-storing power of the soil is generally well pre- 

 served under this type. 



II. The second growth is never endangered by snow or drought 

 or frost or sleet; the old trees remaining do not suffer from storm 

 or sun scald. 



III. Small wood lots may yield a steady annual supply of timber 

 or wood under this type. 



IV. The type is well adapted to deer parks. 



D. Disadvantages : 



I. The operations are very scattering. Indeed, they cover con- 

 tinuously the entire forest or a large percentage thereof. Diffi- 

 culty of supervision. 



II. An intricate system of permanent roads is required, since 

 the axe returns every few years to the same compartment. If the 

 intervals of years are long — say from ten to twenty years — the 

 type is bastardized with the cleared group type or with the shelter- 

 wood group type. 



III. The type as a means of regeneration, in its purity, is pos- 

 sible only where 



a. The compartments contain a mixture of all age classes, 

 with the hypermature classes not too badly prevailing; 



b. The species to be regenerated is an intense shade-bearer; 



L-. The soil is strong enough to allow light-demanding seedlings 

 a chance at surviving a long period of partial suppression. 



IV. The species removed — presumably the most valuable species 

 —has reduced prospects of propagating itself, struggling against 

 competing species, the number of its seed trees being relatively 

 decreased. 



V. Small chance for reinforcing. 



VI. Impossibility of protection against fires under headway. 



Paragraph XL VII. Types in which lumbering coincides with N. S. R. 



In mese types of natural seed regeneration— so-called shelter- 

 wood types— lumbering and reseeding go hand in hand, both pro- 

 gressing seriatim, slowly, cautiously. In the pure types, no tree is 

 removed, unless the removal has a, distinct bearing— or is expected 

 to have it— on the production of a progeny or on- its further develop- 

 ment. Seedlings less than five years old usually stand within a 

 few yards of their mothers. This distance is gradually increased— 

 in the course of up to fifty years— imtil the youngsters do not 



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