ri:ui()l)IC.\I, MTKKATl'kK 8.3 



SILMCULTURE. PROTECTION. AND EXTENSION 



Advocatt's getting away from tliccjry and 

 Forestry Based arbitrary rules and methods in forest manage- 

 0)1 Nature ment, with a closer adherence to natural laws 



and the ])h('nomena of forest growth. Accurate 

 prediction of growth for long periods is impossible, and the most 

 carefully made -theoretical working plans are always sooner or later 

 upset by natural intluences, such as windfall, drough, frost, insects, 

 fires, failure of seed years, and the like. The system proposed has 

 been tried out since 1!>0() on a r».()0()-hectare fir and beech forest in 

 Alsace. An essential feature is the .")-year cutting cycle, by which 

 every part of the forest is gone o\-er every o years. This makes 

 possible the removal of diseased, suppressed, and ripe trees and groups 

 of trees at the most suitable time, and is es])ecially favorable to growth 

 of the remaining trees and to natural re])roduction.' Another feature 

 is the maintenance of a continuous forest cover, unbroken b\' clearings 

 except where they result from accident. The frec|uent cuttings insure 

 light and ventilation. Instead of extensive, pure, even-aged stands, the- 

 age classes are mixi-d together in small groups, as usually occurs in 

 nature, so that the forest takes on the appearance of a selection forest. 

 Because of the long periods required for trees to mature, soil exhaus- 

 tion can not be prevented by rotation of crops as easilv as with other 

 crops. The same result can be t)btained, howe\er, by using mixed 

 stands, comj^osed of species with different soil requirements. The 

 beech is es])ecially \aluable tor im])ro\ing soil fertility, as well as 

 for favoring better development f)f the associated conifers, atid its 

 proportion in the stand can be varied from time to time as conditions 

 require. Other species, such as oak, ma]:)le. ash, elm, birch, alder. 

 and Scotch i)ine. may also be used with beech, provided they are given 

 several years start and are planted in large enough groups so that thev 

 will not be shaded out. For purposes of management forests should 

 be divided into compartments of an average size of not more than 10 

 hectares. At the 5-year intervals, cutting is done, not in accordance 

 with a predetermined working plan, but according to the actual silvi- 

 cultural needs of each individual compartment, and also according to 

 current market conditions. In some, no cutting at all may be done ; 

 others may be cut very heavily. The usual method of determining the 

 annual cut is very complicated, involves much manipulation of figures, 

 and can not be accurate. The average increment and the allowable cut 



