SYLVICULTURE. 



Paragraph XLI. Methods of natural seed regeneration (Enesar). 



A fixed method is applicable in the arts only where a fixed 

 type of conditions exists. Fixed types rarely exist in primeval 

 woods. Hence the impossibility, from a sylvicultural standpoint, 

 to adopt any fixed European method of seed regeneration for direct 

 application in American practice. A second growth, obviously, pre- 

 sents a more fixed set of conditions (it certainly lacks everywhere 

 the hypermature age classes) than a primeval growth; and, conse- 

 quently, it allows of a more methodical treatment. In Biltmore 

 Forest methodical treatment is, therefore, permissible; in Pisgah 

 Forest it is not or not yet indicated. 



The types of seed regeneration might be considered: 



A. According to the relative position of old and new growth: 



I. The young growth develops underneath the old growth: 



a. Whilst the old growth is left intact (natural seed regenera- 

 tion by advance growth), or 



b Whilst the old growth is gradually reduced (natural seed 

 regeneration under shelter woods). 



II. The young growth develops at the side of the old growth 

 (natural seed regeneration from adjoining timber). 



B. According to the size of the units of regeneration, which 

 may be: 



I. Compartments, i. e., a cove, a slope, a top or a coherent 

 part thereof, comprising from ten to one hundred acres. 



II. Strips, i. e., figures of a more or less rectangular form, in 

 which the length is a multiple of the breadth, the latter not 

 exceeding 500 feet. 



III. Groups, i. e., aggregates of growth of a more or less cir- 

 cular form, covering 0.1 to 3 acres. 



IV. Patches, i. e., areas covered by the crown of an individual 

 tree, about one one-hundreths of an acre in extent. 



The figures given are meant to illustrate, and are not meant to 

 define (in this paragraph as well as in the following fifteen para- 

 graphs). 



C. According to the degree in which 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: 



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