158 FOREST REGULATION 



and does not consider other provisions of the plan. But this fact 

 does not prevent a proper development of forest division, order in 

 cutting, or necessary revisions with their .surveys and estimates of 

 all parts of the forest. 



This method recommends itself by simplicity, is adaptive, and 

 fully competent to develop a well regulated forest. Nevertheless, 

 this method never gained favor and was never employed by any of 

 the State forest Departments so that it stands today without any 

 important results or experience, and merely with an academic his- 

 tory in text books. 



c. Combined Methods. Of these the Combined Allotment 

 where the table was made sufficiently large to accommodate columns 

 for areas and for volumes has been the most important. Since this, 

 in actual practice has long changed to the Area Allotment with 

 volume as a check, there is no occasion to go into it further.* 



d. "Diameter Limit" as a Method of Regulation. Diameter 

 limit has been recommended and applied in some of the early efforts 

 in forestry, it has become very generally known, appealing, as it 

 does, to the man in the woods. Its object is not really Regulation, 

 but merely an effort to preserve the forest from immediate devas- 

 tation. 



For this purpose it has served well, at least in a few cases, and 

 is perfectly suited to help in most forests. But good silviculture 

 alone condemns any rigid application of diameter limit for any real 

 forestry, since the runt or small tree is often older and more worth- 

 less to keep in the woods. If this runty stuff is to be cut, then the 

 enterprise is no longer based on diameter limit. As a means of 

 Regulation of Cut it fails because it is based on the mistaken assump- 

 tion that diameter and age are proportional, an assumption always 

 wrong in any forest, regardless of care, and wrong to an extent of 

 30-50%, i. e., in the eighty year old stand, even in a well cared for 

 forest, the largest tree differs from the smallest tree by easily 30- 

 50% in diameter. Even where this diameter limit is used, either an 

 area regulation or a volume regulation such as Von Mantel's should 

 be added. 



* For complete list of the many methods published at different times, see 

 Recknagel, "Theory and Practice of Working Plans." 



