A Brief History of Forestry. B. E. Fernow

A Brief History of Forestry - B. E. Fernow


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being highly cultivated and imbued with the spirit of science. His bent was to systematize the knowledge in existence and extend it by means of exact experiments. In forest organization, he invented the well known formula method or “rational method” of regulating felling budgets and became also one of the founders of Forest Statics (1826) which he called “the doctrine of measuring forestal forces,” being thus the forerunner of modern scientific forestry.

      The fourth of the group, Gottlob König (1776–1849), was a practitioner without a university education, who had enjoyed the teaching and influence of Cotta whom he succeeded in Eisenach as the head of the ducal forest administration. He also founded here a private forest school, which, in 1830, became a state institution, and is still in existence. König became noted by his contributions to the scientific, especially the mathematical side of forestry, developing forest mensuration and statics. In this latter branch he was the forerunner of Pressler and of the modern school of finance. In his “Anleitung zur Holztaxation” (1813) he gives a complete account of forest mensuration and in the part devoted to forest valuation he develops the first soil rent formula and the methods of determining the cost value of stands. His “Forest Mathematics” (1835) in which he introduces factors of form and many other new ideas was an original contribution to science.

      Very different in character from these four leaders was the aggressive, sharp-witted Friedrich Wilhelm Leopold Pfeil (1783–1859), who, without a university education, and in spite of his poor knowledge of mathematics and natural history, advanced himself by native wit and genius. After a brief period of employment in private service, in the province of Silesia, he accepted the position of professor of forestry at the Berlin University, in 1821, in connection with Hartig, with whom, however, he was at sword’s point. It was at his instigation, with the assistance of von Humboldt, that the school was transferred, in 1830, to Eberswalde, Pfeil becoming its director.

      While Hartig was a generalizer, Pfeil was an individualizer, free from dogma, and most suggestive; a free lance and a fighter. Critical in the extreme and prolific in his literary work, he domineered the forestry literature of the day by means of his Kritische Blaetter, a journal of much import and merit.

      The youngest of the group, Karl Heyer (1797–1856), a thoroughly educated man, combined the professorial position in the University of Giessen (1835) with practical management of a forest district, but in 1834 abandoned the latter in order to devote himself entirely to literary work. He was one of the clearest and most systematic expounders, and both his Waldbau (silviculture, 1854) and his Waldertragsregelung (forest organization, 1841) are classics. The last, fifth edition of the Waldbau, appearing in 1906 in two volumes, has been brought up to date by Professor Hess. He devised one of the most rational methods of forest organization, and, imbued with the necessity of basing forest management on exact scientific inquiry, instead of on empiricism alone, he formulated instructions for forest static investigations, a subject which his son, Gustav Heyer, elaborated into a science.

      4. Progress in Silviculture.

      Natural regeneration continued to be the favorite method well into this period, and, for a long time, selection forest and coppice were all that was known in practice until Hartig and Cotta forced recognition of the shelterwood system.

      The only way in which a transition from the generally practiced, unregulated selection forest to an intensive management was possible, with the ignorant personnel of underforesters, was to formulate into an easily intelligible prescription the necessary rules, allowing the least play to individual judgment. This was done by Hartig when he formulated his eight “General Rules” (1808) which coincided also closely with the teachings of Cotta. Since these rules represent in brief and most definitely the status of silvicultural knowledge on natural regeneration at the time, it may be desirable to translate them verbatim.

      (1) “Every forest tree which is expected to propagate itself by natural regeneration must be old enough to bear good seed.

      (2) “Every district or stand which is to be replaced by a thoroughly perfect stand by means of natural regeneration, must be brought into such position (density) that the soil may everywhere receive sufficient seeding.

      (3) “Each compartment must be kept in such condition (density) that it cannot, before the seeding takes place, grow up to grass and weeds.

      (4) “With species whose seed loses its power of germination through frost, as is the case with the oak and beech, the compartments must be given such a position (density) that the foliage which after the fall of seed covers and protects the same cannot be carried away by wind.

      (5) “All stands must be given such density that the germinating plants in the same, as long as they are still tender, find sufficient protection from their mother trees against heat of the sun and against cold.

      (6) “So soon as the young stand resulting from natural regeneration does not any longer require this motherly protection, it must gradually, through the careful removal of the mother trees, be accustomed to the weather, and finally must be entirely brought into the open position.

      (7) “All the young growths, whether secured by natural or artificial seeding, must be freed from the accompanying less useful species and from weeds, if these in spite of all precaution threaten the better kinds.

      (8) “From every young forest until it is full grown, the suppressed wood must be removed from time to time, so that the trees which are ahead or dominate may grow the better; the upper perfect crown cover, however, must not be interrupted until it is the intention to grow a new forest again in the place of the old one.”

      Since these rules are applicable only in beech forests, much mischief and misconception resulted from their generalization; pure, even-aged high forests became the ideal, and the mixed forest, which was originally the most widespread condition, vanished to a large extent. This was especially unfortunate in Northern and Northeastern pine forests.

      A reaction against Hartig’s generalization began about 1830, under the lead of Pfeil. He had at first agreed with Hartig, and then with equal narrowness advocated for many years a clear cutting system with artificial reforestation. Finally, however, he was not afraid to acknowledge that his early generalizations in this respect were a mistake, and that different conditions required different treatment.

      In the development of the shelterwood system there was at first, under the lead of Hartig, a tendency to open up rather sharply, taking out about three-fourths of the existing stand, but gradually he became convinced that this was too much, and finally reduced the first removal to only about one-third of the stand. This was the origin of his nickname of Dunkelman. In spite of the fact that it was claimed that Cotta took the opposite view (for which he was called Lichtman), he, too, grew to favor a dark position, and, as he progressed, leaned more and more towards more careful opening up. Hartig originally recognized only three different fellings: the cutting for seed; the cutting for light; and the removal cutting. By and by, a second cut was made during the seed year, and the number of fellings to secure gradual removal were increased, so that, by 1801, this system seems to have been pretty nearly perfected to its modern conditions. The best exposition of this Femelschlagbetrieb (shelterwood system), as then developed, is to be found in Karl Heyer’s Handbook, 1854.

      The method was unfortunately extended by Burgsdorf (1787) to the Northern pineries with a seventy year period of rotation. Within ten years, however, he recognized its inappropriateness, and modified it by instructions to leave only six to twelve seed trees per acre. His successor, Kropff, reduced the number of seed trees to four or five, which were to be removed within two or three years. In spite of the development of this more rational method, the practitioners under Hartig’s approval, held mainly to a dark position even for pine, much in the manner of a selection forest, which produced a poor growth of oppressed seedlings, retarding for a long time the development of the pineries.

      In spruce or fir, either a pure selection forest or a strip system was employed. Attempts at a shelterwood system were made, but experience with the wind danger soon taught the lesson that this was not a proper method with shallow-rooted species. Even Hartig


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