Buffon, in 1739, proposed a treatment for the pineries to secure natural regeneration by cutting one-third to one-half, leaving 40 to 50 seed trees per acre, while Duhamel (1780) considers selection method best for larch and pine as well as fir, although pine might, like oak, be readily reproduced by sowing.
While system and orderly progress of fellings in selection forest had gradually been established, during the revolution this was largely disregarded and unconservative fellings became the order.
Guiot’s Manuel forestier, published in 1770, gives a good idea of the status of forestry at that time. It appears that for timber forest, mostly royal woods, rotations varying from 60 to 200 years, for coppice from 10 to 20 years, were in use on the royal domain; that fellings were regulated according to species, soil quality and the most advantageous yield. To facilitate regeneration, a superficial culture of the soil is also advocated.
The prescription of Colbert’s ordinance to leave a certain number of seed trees, no matter for what species or conditions of soil or climate had as early as 1520 been pointed out as faulty by one of the grand masters, Tristan de Rostaing, who had recommended a method of successive fellings. This prescription, applied pretty nearly uniformly as a matter of law, removed from the officials all spirit of initiative and desire or requirement of improving upon it. No knowledge beyond that of the law was required of them, hence no development of silvicultural methods resulted during the 17th and 18th century. The seed trees left on the felling areas grew into undesirable and branchy “wolves,” injuring the aftergrowth, or else were thrown by the wind or died, and many of the areas became undesirable brush. Not until the first quarter of the 19th century was a change in this method proposed through men who imported new ideas from Germany.
When the inefficiency of the méthode à tire et aire was recognized, the only remedy appeared to lie in a clearing system with artificial reforestation (recommended by Réaumur and Duhamel); and, indeed, the ordinance of 1669 recognized the probable necessity of filling up fail places in that manner. Yet the success of the plantings in waste lands does not seem to have brought about much extension of this method to the felling areas. As late as 1862, Clavé, complaining of the conditions of silviculture in France, and of the ignorance regarding it, refers to the clearing system as méthode allemande, the German method. The shelterwood system, la méthode du réensemencement, which was introduced in theory from Germany by Lorentz in 1827, was hardly applied until the middle of the century. Indeed, the promulgation of this superior method cost Lorentz his position in 1839, and other officers suffered similarly for this “German propaganda.” (see [p. 242])[7]
[7] In this statement we follow Clavé and other authors. Huffel takes exception to this conception of the origin of the shelterwood system, because he finds in some documents allusion to a modified application of the tire et aire method which might be construed into shelterwood regeneration. Indeed, Guiot (1770) and Varennes de Fenille (1790) describe methods of procedure which resemble somewhat this method of regeneration. But as the method of successive fellings was practised in Germany since 1720, and fully developed in all its detail by 1790—Hartig formulating merely into rules what was long practised—it is likely that the French authors had heard of it. Moreover, in another place (vol. III, p. 271) Huffel says: “At this time (1821) one made several tentative regeneration cuttings by successive fellings according to the new formula—but without success.”
At the present time large areas of coppice and of coppice with standards characterize the holdings of the municipal and private owners, and the selection forest still plays a considerable part even in the State forests; the method of shelterwood in compartments, being still more under discussion than found in practice.
The main credit for advance in silvicultural direction which belongs to the French foresters in particular is the development of new and fertile ideas regarding the operations of thinnings; here the differentiation of the crop into the final harvest (le haut) and the nurse crop (le bas) (see [page 105]) and the differentiation of the operations, par le haut and par le bas, seems to have been for the first time described by Boppe in 1887. Indeed, the theory of thinnings, at least, seems to have been well understood by Buffon, who advanced his theories in a memoir to the Academy of France, in 1774, and gives a very clear exposition of the value of thinnings and improvement cuttings.
Nevertheless, thinning practice, while often accentuated in the literature, is too often omitted in practice, or exercised only in long intervals, while otherwise silvicultural practice is excellent, especially in the coppice. Most valuable lessons may be had especially from the experience in converting coppice into timber forest.
At the International Congress of Silviculture, convening in connection with the Universal Exposition in 1900, supposedly the best home talent was represented, but it cannot be said that anything new, or striking, or promotive of the art or science transpired. The desirability of establishing experiment stations outside the one in existence at Nancy (established in 1882), and the desirability of constructing yield tables still required arguments at this meeting.