ORIGINAL WORKING PLAN DATA 513 



From 1884 to 1895 the increment per hectare and per year has been 11.97; the volume 

 for the average hectare, 385. The increment per cent, 3.11. 



In 1883 the volume analysis of trees 0.30 in diameter and above was: Logs, 206,058 

 cubic meters; branches, 18 per cent, 37,090 cubic meters; total, 243,148 cubic meters. 



This being true it is possible to make the following conclusions from a comparison of 

 the stocktaking of 1883 and 1908: Volume of trees 0.30 in diameter and above, inven- 

 tories in 1883, 243,148 cubic meters; in 1908, 325,675 cubic meters; increase, 82,527 

 cubic meters. 



Volume of trees cut from 1884 to 1908: 1884 to 1885, 60,280; 1896 to 1908, 100,731; 

 total of 161,011 cubic meters. 



Total growth from 1883 to 1908 = 82,527 + 161,011 = 243,538 cubic meters or 



average per year of 9,741 cubic meters. 



, , 243,148 + 325,675 „„. -^^ , • 

 Average growmg stock — ^ = 284,406 cubic meters. 



Average volume per hectare 284,406 _ . .„ , . , 



243 538 

 Growth per hectare and per year ' _ = 15.2 cubic meters. 



D4u.oy X ^0 

 , ^ , 15.2 X 100 „ , 

 Increment per cent jj^ = 3.4 per cent. 



It results from the analysis of the preceding stocktakings (the volume per hectare 

 was 380 cubic meters in 1883 and 500 cubic meters in 1908 (wood 0.30 and over)) that 

 the growth per hectare and per year estimated at 11.97 cubic meters for the first 12 

 years of growth is between 3.11 and 3.40 per cent. 



These figures prove . . . that we have a working group overstocked with old 

 wood, where for the past 25 years the material has been increasing in spite of the annual 

 cut (yield). . . . 



In view of this rather abnormal situation, it is felt that in order to prevent a further 

 accumulation of excess growing stock it is best to base the yield upon the growth per cent 

 of the working group during the last period of 25 years by multiplying the estimated 

 growing stock by the mean annual growth per cent. 



Material enumerated in 1908 = 301,260; growth per cent from 1883 to 1908 = 3.4; 



yield = ?0L??0^4 . 10.242. 



Note. — For the comparison the same volume table was used to obtain both volumes, 

 i.e., in 1883 and 1908. 



If we should only cut as in the past, the average annual growth of the working group, 

 it would be impossible to realize with sufficient rapidity the overmature material and it 

 is feared the present state of affairs would continue indefinitely. It is therefore felt 

 to be absolutely necessary . . . during two periods ... to add 10 per cent 

 of the volume to the yield obtained and to fix (the cut) at 10,242 + 1,024 = 11,266 

 cubic meters, or, roughly, 11,270 cubic meters equal to 17.585 per hectare and per year 

 and 3.7 per cent of the total growing stock. 



According to Inspecteur Devarennes "the State forest of La Joux ^ is one of the richest 

 and most productive fir stands in France, and perhaps even of all Europe." The stock- 

 taking made in 1908-1909 gave the following figures: 642,138 trees from 7.9 to 55.1 

 inches in diameter (245 trees or 463 cubic meters per hectare or about 42,400 feet 

 hoard measure per acre, average on 6,531 acres). This is equal to 15.8 cubic meters per 

 hectare per year (a yield per cent of 5.3) or about 1,200 board feet and 1.6 cords per acre 



1 This forest was logged by the Canadians for the French; the cutting started in 1917 

 before the A. E. F. arrived in France. 



