130 Oermcmy. 



The discussion of what should be considered the 

 proper felling age or rotation naturally occupied the 

 Hiinds of foresters from early times ; a maximum volume 

 production being originally the main aim. As early as 

 1799, Sautter had recognized the fact that the culmina- 

 tion of volume production had been obtained when the 

 average accretion had culminated. Hartig, in 1808, 

 made the distinction of a physical, an economic and a 

 mercantilistic, i. e., financial felling age, and Pfeil, con- 

 siderably ahead of his time is the first to call (1830) for 

 a rotation based on maximum soil rent. As, however, 

 he had so often done, he changed his mind, and while he 

 first advocated even for the state a management for 

 the highest interest on the soil capital involved, he later 

 rejected such money management. About the same time 

 Hundeshagen clearly pointed out the propriety and 

 proper method of basing the rotation on profit calcula- 

 tions, but it was reserved for a man not a forester to 

 stir up the modern strife for the proper financial basis, 

 namely Pressler, a professor of mathematics at Thar- 

 and, who became a sharp critic of existing forest man- 

 agement and developed to the extreme the net yield 

 theories. 



It was then that the danger of a shortening of the ex- 

 isting rotations, due to the apparent truth that long ro- 

 tations were unprofitable, called for a division into the 

 two camps alluded to ; G. Eeyer, Judeich and Lehr, elab- 

 orating especially the mathematical methods of the soil 

 rent theory, Kraffi and Wagener came to the assistance 

 of Pressler, while Burhhardt, Bose, Baur, Borggreve, 

 Danhelmann, Fischhach and others, pleaded for a differ- 

 ent policy for the state at least, namely, the forest rent 

 with the established rotations. 



