ORIGINAL WORKING PLAN DATA 511 



(C) Working group Rein des Boules, Forest of Ban d'fitival altitude of 510 meters, 

 37.04 forested. Species by volume, fir 69 per cent, beech 31 per cent; selection. Yield 

 by number of trees. 



By the decree of October 15, 1885, approved November 27, 1886, the working group 

 was divided into ten approximately equal felling areas and an annual yield of 41 trees 

 at least 0.30 in diameter at 1.30 c. m. (about 16 fir and 25 beech) was established includ- 

 ing the provision that windfalls 0.30 and over would count as part of the yield. The 

 41 trees to be cut were based on the estimate that the growth was 4.5 c. m. per hectare 

 and per year and that the fir of 0.60 meters in diameter contained 3.7 c. m. and the 

 beech of the same size 4.4. On the basis that four fir would be cut to every six beech 

 the average volume per tree was taken at 4.12. Owing to windfalls, etc., they cut 

 38 fir and 12 beech or 50 trees per year during the years 1886 to 1895, but as a matter 

 of fact the average volume was only 2.8 per tree. During the second cutting cycle 

 the cut was actually 54.9 trees and over per year (8.9 accidental) with an average volume 

 of 4 c. m. per tree. Actually during the first 29 years the production was 9.4 cubic 

 meters per hectare and per year or 8 in wood 0.45 and above and 1.4 in wood 0.15 to 

 0.40. The working plans officer quotes what is considered an average selection hectare 

 for the locahty, namely, a total of 434.5 trees cubing 388.2 cubic meters. 



In the calculation of the new yield the author, M. Cuif, proceeded as follows: During 

 the 20 years 1885-1905 the average production was 58 trees — 31 fir and 27 beech. 

 "The 31 fir and 27 beech have been furnished actually by the trees 0.40 in diameter 

 whose average number may be valued as follows, taking 771 as existing in 1885 (429 

 fir and 342 beech), 1,004 in 1896 (392 fir and 612 beech) an average of 412 fir and 463 

 beech; 412 fir 0.40 in diameter have given each year, 31 fir to be counted against the 

 yield or 7.5 per cent and 463 beech, 27 beech or 5.8 per cent." Similarly the per cent 

 passing to the next diameter class is figured, and the following results obtained: 



Diameter Average per cent of passage 



(cm.) to next diameter class 



40 6.6 



50 7.7 



60 8.2 



70 9.6 



80 10 



90 12 



Finally the writer calculates for each compartment or cutting area the normal number 

 of trees to cut, and in addition one-quarter the excess over the normal stand also to be 

 cut, in order to reduce the growing stock, namely, 540 normal cut plus 160 trees as 

 one-quarter the excess or 700 in all on 37.04 hectares. This is then divided between 

 beech and fir on the basis of their per cent in each compartment. 



One cannot but ask the question: "Why regulate the yield by number of trees if 

 it has to be checked by a volume computation?" But it must be recalled that these 

 three working groups are really large scale experiments on yield regulation; the con- 

 clusions will probably be available by 1921 or 1931. 



(3) COMMUNAL FOREST OF MONT GLORE (SAVOIE) 



The working plan of 1885 quotes from a report dated 1842 which alludes to this for- 

 est as "Abused, impoverished in 1835 by a cut every three years of 150 fir trees." In 

 other words, the yield was by number of trees (and probably the best were unfortunately 

 selected) instead of by volume. This report spoke of this forest as having 90 hectares 

 stocked with fir, 90 with beech with a fir under-story, and 145 pure beech coppice, making 

 a total of 335 hectares of forest. The management prescribed thinnings on one-fifteenth 



