120 THE THEORY AND PRACTICE OF WORKING PLANS 



with too strict construction it results in crass errors, such as 

 the needless leaving of overmature stands simply because they 

 are in the sacrosanct II period and can not be touched,* or the 

 cutting of immature stands which were placed in the I period 

 merely to " fill in." 



(b) Example. — Since, from what has gone before and what 

 follows (c) these methods are so ob\'iously unsuited to American 

 conditions, it would serve no useful purpose to elaborate them 

 by examples.! 



(c) Value of Application. — In most of the German States 

 the " framework " methods were the foundation of regulated 

 management and thus exerted a mighty influence on German 

 forestry. But under the conditions of modern times they 

 have steadily diminished in importance for the following 

 reasons : 



(i) The silvicultural method of management, to which the 

 method of regulating the cut must conform, is often in direct 

 disagreement with the " framework " method. The latter 

 demands that the cutting on a given parcel (e.g., compart- 

 ment) be completed within the period (twenty years). This 

 is often impossible without silvicultural mistakes and economic 

 sacrifices. The natural reproduction of many species requires 

 more than an arbitrary period of, say, twenty years. Even 

 with artificial reproduction there are often unavoidable and 

 unforeseeable events which make complete regeneration im- 

 possible within the period. 



(2) The concept of sustained yield which endows each period 

 with an equal area or volume, or both, is unnecessarily narrow. 

 For practical purposes it suffices that the area or volume, or 



* This has led to the growing demand for the " Opening of the II Period." 

 t These may be found in Judeich's or Martin's " Forsteinrichtung," or in 

 Lorey's " Handbuch der Forstwissenschaft," 2d ed., Vol. Ill, pp. 411, 415, and 

 423, or in Roth: " Forest Regulation," pp. 142-145, 147-150, who gives, what he 

 calls the " Allotment Methods," a strong endorsement, despite the fact that most 

 of the European countries have outgrown them. This endorsement is all the 

 more strange since Roth values Dr. Martin so highly as an authority and Martin 

 himself repeatedly declares against the period methods. 



