AMERICAN SYLVICULTURE 



By "advance growth" is understood an aggregate (small or 

 large) of seedlings or saplings belonging to a desirable species and 

 formed without any human intention or attention, solely by nature, 

 beneath a totally or partially untouched leaf canopy overhead. 



[Misshapen advance growth appearing in bunches or groups can 

 be doctored up with axe and brushhook and machetes, by an appli- 

 cation of " hairdressing." 



Where the advance growth is not freed, by one single operation, 

 from the superstructure of parents and step-parents overhead, the 

 advance growth types are further bastardized with the shelterwood 

 types. 



Paragraph LIII. The advance growth compart- 

 ment type of natural seed regeneration. 



A. The type is applicable where large areas exhibit on 

 strong soil a uniform advance growth, consisting of seedlings, of 

 saplings and possibly of small poles. 



Previous to lumbering, the leaf canopy consists of two tiers: 

 an upper tier formed by the parents (or step-parents) and a lower 

 tier formed by the advance growth. Lumbering removes the upper 

 tier entirelj' and leaves the lower tier intact — if possible. 



In the safety of the lower tier lies the great difficulty of the 

 system, especially on rough ground, in handling heavy logs of the 

 superstructure, in dealing with cheap stumpage. in cutting soft 

 woods characterized by small healing power and in the absence of 

 an intricate system of transportation. 



Where the upper story of trees consists of say 10,000 feet b. m. 

 per acre, or of more, the ground is literally littered with logs or 

 boles during the logging operations, and the advance growth has but 

 a slight chance to survive the death of its progenitors. 



B. Actual application: The type is found, in rare cases, 

 abroad imder the misnomer of a modified " selection system," where 

 and when the logger returns for a wholesale removal of mature 

 trees, at intervals of about twenty years, to the same compart- 

 ments. 



The type is also practical where prolific seed years produce, 

 in mild sites and on strong soil, a uniform advance growth in even- 

 aged Beech or Firwoods, without any previous human interference 

 with the leaf canopy overhead (so-called regeneration from a com- 

 plete growing stock). 



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