SYLVICULTURE. 



II. Age-classes: The number of age-classes in a normal over- 

 wood equals the fraction 5 wherein 



R represents the length of the rotation in the overwood, and 

 r represents the length of the rotation in the underwood. 

 The normal difference of age between consecutive classes is " r " 

 years. 



III. Xormal formation: The overwood is composed of "stand- 

 ards " regenerated, at the year of coppiced underwood, from self- 

 sown seed falling from the overwood or, in the cultured forest, from 

 planted seedlings. The seedlings of the overwood grow up im- 

 merged and often badly endangered in the new underwood. When 

 this is coppiced at the age of r years, an improvement cutting 

 taices place simultaneously removing misshapen or damaged stand- 

 ards of the various older classes as well as the weaklings in 

 the youngest class. By this improvement cutting the leaf canopy 

 of the standards, which has had ample chance of enlargement 

 during the past r years, is cut back to a normal limit. 



The older an age-class is, the smaller is the number of its- 

 constituents. 



C. Aonormal formation of overwood and underwood: 

 A normally proportioned and normally formed overhead is 

 never found. Deficiencies lie 



1. In a lack of one or the other age-class; 



2. In an abnormal number of constituents per class; 



3. In the fact, that the overwood is partially recruited from 

 stoolshoots and not from seedlings. 



Abnormal coppice over-standards is the usual consequence of the 

 culling of primeval hardwoods or of primeval pineries forming a 

 superstructure over Oaks, Hickories, Gums, etc. 



The burned slopes and outskirts of the Alleghanies usually 

 belong to the coppice-under-standard form. The fire-coppiced under- 

 wood here consists of Soft Maple, Calmia, Rhododendron, Chestnut, 

 Oaks, Hickories, Black Gum, Sourwood, Halesia, etc., etc., all of 

 which are usually devoid of value. 



Culled and fired forest of Pinus echinata, taeda and paustris 

 frequently belong to the same form, with Oaks in the underwood 

 and the Pines in the overwood. 



Paragraph LXXIV. Pedagogy of coppice-under-standards forest. 



Coppice under standards is or may be tended by cleaning, 

 weeding, improvement cuttings, pruning and thinning. 



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