CONTINENTAL NOTES — GERMANY. 1 87 



sizes. The area check, originally introduced by Frederic the 

 Great, was once more accepted as the simplest and safest basis 

 for the forest management of the future, after four other more 

 or less complicated methods had been experimented with for 

 ninety years. The material available in the compartments 

 falling into the first period of twenty years was ascertained, 

 and it was prescribed that the annual exploitation should not 

 exceed one-twentieth of such amount. This, however, was and 

 is subject to the general prescription, that any accumulation of 

 surplus material found to exist at the end of three years may be 

 felled. It was further laid down, that thinnings were to return 

 over the same area every ten years. The excised areas, near 

 Eberswalde, were divided into three sections, to be known as the 

 Park-blocks; they were divided into 10 compartments each, 

 one of which was to be exploited each year under a selection 

 treatment, with a felling age estimated at 120 years. This 

 treatment was adopted partly in order to have a forest area 

 available for independent experiments, trials with exotics, and 

 for educational purposes, partly to beautify the surroundings 

 of the forest school. These Park-blocks, originally a mixed 

 forest of Scots pine and beech, contain now a large variety of 

 different species. The preliminary work in connection with this 

 revision was, for purposes of instruction, carried out in a, for 

 ordinary purposes, unnecessarily detailed and complicated manner. 



In 1888 a short control revision took place, but no changes 

 were made. The periodical revision of 1898 showed again 

 that no changes were required in the management of the 

 Biesenthal division. In the Eberswalde division, however, 

 considerable areas of Scots pine, planted on old fields, had been 

 attacked by Polyiiwrphus afinosus, and had died at an age of 

 from 50 to 60 years. This necessitated a rearrangement. The 

 attacked areas had, for the time at least, to be treated by selection, 

 and were for this purpose formed into four special blocks. 



The total outturn from Eberswalde alone now amounts to 

 some 18,500 cubic metres, and the net annual income to nearly 

 jQ2 per hectare. The gross income of the whole area com- 

 prised in the old Bisenthal forest has risen from ^,^1500 in 

 1818 to ^18,000 in 1906. 



Many, and often serious and costly, disappointments have so 

 far attended the attempts to afforest old farmlands, heather areas 



