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THP] NORMAL A(4E CLASSES. 



Coupe No. 19. 

 19 years old trees = 10 acres 

 39 ,, ,, ,, = 10 .. 

 59 „ „ ,, = 10 „ 

 79 ,, „ „ = 10 „ 

 99 „ „ „ = 10 ,. 



Total = 50 acres 



Coupe No. 20 {oldest). 

 20 yeai"s old trees = 10 acres 

 10 ., „ ,, =10 „ 

 BO ,, „ „ = 10 „ 

 HO „ ,, „ = 10 „ 

 100 „ „ „ = 10 „ 



Total = 50 acres 



Each year the 100 years old trees in the oldest coupe 

 would be cut, which should cover an area equal to one-fifth 

 of the coupe, equal to 10 acres, thus cuttin^:; once the whole 

 area of the forest in 100 years. It is needless to add, 

 that such regularity is never reached in practical forest 

 management. 



3. Distribution of the Age Classes over the Forest. 



By a normal distribution of the age classes is understood 

 that, which admits of a proper succession of cuttings, so that 

 each wood is cut at the proper age, and that the other woods 

 are protected against external dangers, in so far as this can be 

 done by careful management. 



It has already been explained, that every deviation from the 

 normal age interferes with the full realisation of the objects of 

 management ; hence, the age classes should be so distributed, 

 that no such deviations are called for. Of special importance, 

 in this respect, are threatening dangers, such a's damage 

 by strong winds, dry air currents, danger from frost, fire, 

 insects, etc., and sometimes considerations for a successful 

 regeneration. 



StroiKj u'iii(h or (/ales are a most important consideration. 

 Their prevailing direction must be ascertained, and cuttings 

 must proceed against it. Assuming, that the strong winds 

 generally blow from the west, the youngest age class should, 

 at the commencement, be situated at that side and the oldest 



