482 



NA TURE 



[March 26, 1903 



A FRENCH WORK ON SYLVICULTURE. 

 Traits de Sylviculture. Principales Essences Foresticrcs. 

 By Prof. P. Mouillefert. Pp. xii + 544. (Paris: 

 FeUix Alcan, 1903.) Price 7 francs. 



PROF. MOUILLEFERT, who has taught forestry 

 at the French National Agricultural College of 

 Grignon (Drome) since 1875, is publishing his lecture 

 notes in the form of an elementary manual of forestry. 

 This he considers necessary for agriculturists and 

 others in spite of the fact that there are already works 

 by Boppe and Jolyet, Broillard and other eminent 

 foresters on the subject. The work is to be in four 

 volumes, of which the present is the first, and deals 

 with the chief French forest species, including exotic 

 trees that thrive in France. The second volume will 

 deal with the management of woodlands, the third 

 with their valuation, and the fourth with artificial plant- 

 ations, the afforestment of waste land and the restor- 

 ation of inferior woodland. 



The objects set forth as the basis of French forestry 

 are : first, to obtain from a forest the greatest annual 

 revenue in the most advantageous manner; secondly, 

 to secure the natural regeneration of woods by grow- 

 ing species best adapted to the soil and climate; thirdly, 

 to improve the soil as much as possible by rational 

 sylviculture. 



The first volume begins with some interesting statis- 

 tics. The area of French woodlands is about 37,000 

 square miles, 18 per cent, of the total area of the 

 country, while there are about 24,000 square miles of 

 heath, mountain land, swamps and peat-moor, most 

 of which might be planted. Of the actual woodlands, 

 68 per cent, are in private hands, 11 '8 per cent, belong 

 to the State and 20^2 per cent, to d£partements, com- 

 munes and public establishments (hospitals, &c). 

 Private people can clear their woodlands for agri- 

 culture on application to Government, except when 

 their maintenance is necessary to prevent landslips in 

 mountainous country, erosion by water-courses, for the 

 protection of sand-dunes, for military defence, or sani- 

 tation. About one-third of the woodlands is in plains 

 (0-200 metres above sea-level), one-third in hills (200- 

 500 metres), and the rest in mountains. France is 

 subdivided into three climatic districts — the warm dis- 

 trict, with Quercus Ilex and maritime pine; the temper- 

 ate district, with beech, oaks and artificial plantations 

 of Pinus sylvestris; and the cold mountainous district, 

 with silver-fir, spruce, larch, mountain and Cembran 

 pines. Although the author omits Pinus sylvestris in 

 this district, the tree grows naturally in Savoy, Dau- 

 phiny and Provence, as well as in the Cevennes and 

 the Pyrenees. 



As regards the management of the forests, nearly 

 half the area is simple coppice, producing little besides 

 firewood and tanning bark, while one-fourth of the 

 area is under coppice-with-standards, yielding oak, 

 ash and other standards, besides the underwood. Only 

 about 9000 square miles are high forest. There is an 

 error in the areas given by the author for the different 

 systems or I would have quoted them. The total pro- 

 duction of wood in 1892 was about 21 millions of tons, 

 of which 5^ million tons were timber, the rest firewood. 

 NO. 1743, VOL ' 67] 



This gives 40 cubic feet per acre as the annual yield; 

 only one-fourth of this is timber, though in the State 

 forests one-third of the average annual yield (41 cubic 

 feet) is timber. In three d^partements (Aisne, Nievre, 

 Doubs) the average annual yield of forests exceeds 70 

 cubic feet per acre, while in the mountain regions 

 (Pyrenees, Hautes Alpes, Basses Alpes) it falls to less 

 than 14 cubic feet. 



The total average annual sales of wood, bark and 

 resin amount to 9,470,000?., or about eight shillings 

 per acre, but the value of the hunting, shooting, 

 quarries, pasture and other minor produce is not 

 therein included, the author estimating their value at 

 6d. per acre in State forests and is. per acre in private 

 forests. 



He does not estimate the cost of management, but 

 as natural regeneration is chiefly practised and the 

 wood is sold standing to purchasers, who are frequently 

 debited with the cost of repairs to roads and with 

 cultural operations, which they pay for out of the value 

 of the timber, these charges not being debited in the 

 accounts, the expenditure is chiefly that of supervision 

 only, which Broillard estimates at about 8<2. per acre. 

 If, therefore, we wish to estimate the net revenue from 

 French forests, we may allow that minor produce pays 

 for maintenance, while the price of the wood is net 

 profit. With this proviso the following statement 

 shows their average capital value and yield. 



Nature of woodlands. 



State forests ... 

 Communal forests . 

 Private forests 



Average 



capital value 



per acre. 



£ s. d. 

 20 10 O 



14 16 O 



I250 



Net revenue 

 per acre. 



7. a. 



'3 ° 



9 5 



7 7 



Rate 

 per cent, 

 on capital. 



3-15 



In some departements, as in Aisne (beech and oak), 

 the average revenue per acre is said to be il. 135. <\d. 

 and the capital value 54?. 13s., while some of the silver- 

 fir forests in the Vosges are at least as valuable, though 

 this is not stated by the author. 



As regards prices of wood, although the use of coal, 

 and of coal-gas for cooking, is steadily replacing that 

 of firewood in Paris and other large towns, yet the 

 price of firewood (about lhd. per cubic foot in the forest) 

 has remained steady throughout the last century, while 

 that of timber has more than trebled, good standing 

 oak trees being now about is. qd. per cubic foot with- 

 out top and lop. 



There is a good chapter on the influence of forests 

 on water-supply and climate, and it is shown that 

 forests drain the soil, but keep the upper layer (15-20 

 centimetres) moist. The great transpiration of forests 

 maintains a prism of cool, moist air above them, 1000 

 to 1500 metres thick, and this is readily perceived when 

 the forests are passed by balloons, the latter descend- 

 ing in such cases unless ballast is thrown out. As re- 

 gards the subsoil, it is found that the water-level is 

 4 or 5 metres deeper in forests than in the open country, 

 .1 1 though the rainfall is sensibly greater in the former 

 (100 : 77 in the Foret de Have, near Nancy). Climate 



