Kitabı oku: «A Brief History of Forestry.», sayfa 6
9. Improvements in Methods of Mensuration
In scientific direction, the mathematical disciplines were the first to be developed; the natural sciences received attention much later.
A considerable amount of mathematical knowledge was required for this work of forest organization. The mathematical apparatus of the foresters even at the end of this period was rather slender, but its development went hand in hand with the development of these methods of regulation; and even elaborate mathematical formulæ for determining felling budgets were not absent.
Until nearly the middle of the 18th century, surveys of exact nature were almost unknown; only when the division into equal or proportionate felling areas became the basis for determining the felling budgets, did the necessity for such surveys present itself.
Plane table and compass were the instruments which came into use in the beginning of the 18th century. But not until the latter half of that century were extensive forest surveys and maps of various character made, especially in Prussia under Wedell, Kropff and Hennert.
The methods of measurement of wood developed still later. Until Oettelt’s time no method of precise determination of volumes was known, everything being estimated by cords or by diameter breast-high and height, or by the number of boards which a tree would make (board feet?).
The diameter was sometimes used as a price maker, the price increasing in direct proportion to the diameter increase. Oettelt calculated the volume of coniferous trees as cones, and Vierenklee, who wrote a book on mathematics for the use of foresters, calculated timbers with the top removed by using the average diameter, to which Hennert added the volume of a cone with the difference of the two diameters as a base, to make the total tree volume.
Most measurements of standing trees were, of course, made on the circumference, for, in the absence of calipers, the diameter could be directly measured only on the felled tree. Doebel had already measured the height by means of a rectangular triangle, and the first real hypsometer with movable sights was described by Jung in 1781; and a complete instrument, which could be used for measuring both height and diameter at any height, similar to some more modern ones, was constructed by Reinhold.
Determination of the real wood contents in a cord of wood and of the volume of bark by measurement was taught by Oettelt, and the method of immersion in water and measuring the displaced volume, by Hennert (1782).
In 1785, Krohne first called attention to the variation of the increment in different age classes and the need of determining the accretion for each separately.
In 1789, Trunk taught how to determine average felling age increment, and also the method of determining the change of diameter classes, which is now used by the United States Forest Service: “On good soil a tree grows one inch in three years, on medium soil in four years, on poor soil in five years.” With this knowledge, the attainment of a given diameter, or the change from one diameter or age class to the next could be calculated.
Volume tables were at Trunk’s command, and Paulsen in 1787, Kregting in 1788, mention periodic yield tables; but generally speaking “ocular taxation” or estimating was the rule, checked by experience in actual fellings, the method of the American timber looker. Generally, of course, only the log timber was estimated as with us, and only the very roughest estimating or rather guessing was in vogue until near the end of the period.
The first attempt at closer measurement was made by Beckman (1756), who surrounded the area to be measured with twine, drove a colored wooden peg into each tree, one color for each diameter class, when, knowing the original number of pegs that had been taken out, the difference gave the number of trees in each diameter class, and by multiplying the average cubic contents of a measured sample tree in each class by the number in the class its volume was found.
The method, often employed at present, of ascertaining by tally the diameter classes on strips forty to fifty paces wide, the so-called strip survey, was described by Zanthier in 1763.
These measurements were usually confined to sample areas, the use of such being already known in 1739. The contents of the sample area, if a special degree of accuracy was desired, were ascertained by felling the whole and measuring.
Oettelt, of mathematical fame, was the first to publish something about the determination of the age of trees by counting rings, although the practice probably antedates this account. He knew of the dependence of the ring width on the site and on the density of the stand.
It seems that long before this time the French had made the determination of yield in a more scientific manner, Réaumur reporting in 1721 to the French Academy comparative studies of the yield of coppice and of volumes of wood.
Oettelt, too, laid the foundation of forest financial calculations when he ascertained the value of a forest by determining the value of an acre of mature wood – the oldest age class – and multiplying it by half the acreage of the whole forest, suggesting the well known expression for the normal stock soon after to be developed by an obscure Austrian tax collector.
Even the first forest finance calculations with the use of compound interest, and a comparison of the profitableness of the different methods of management, are to be recorded as made by Zanthier in 1764, bringing the beginning of forestal statics into this period.
10. Methods of Lumbering and Utilization
At the beginning of this period, rough exploitation was still mainly in vogue, only parts of trees being used, just as in the United States now. Here and there, attempts were made toward more conservative use; for instance, at Brunswick in 1547, the use of log timber for fuel was discouraged; in Saxony, as early as 1560, the brushwood was utilized for fuel. High stumps were a usual feature in spite of the threats of punishment of the forest ordinances, as in Bavaria (1531). The axe was the only instrument used until the end of the 18th century for felling as well as cutting into lengths; not until 1775, do we find an allusion to the use of the saw, when the forest ordinance of Weimar ordered that the saw-cut should be made for three-fourths of the tree’s diameter and the axe be used to finish (!) the last quarter. Not until the 18th century was the fuel-wood split in the woods, and it was near the end of the period before it was set up in mixed cords (round and split) after the splitting had been introduced. The measurement was, until about that time, made merely in loads, the cord being of later introduction.
The value of low stumps and of the use of the saw was recognized in Austria in 1786. To show how variously and locally the need of conservative use of wood developed, we may cite the fact that in the Harz, about 1750, trees were dug with their roots as now in some of the pineries of the Mark Brandenburg, in order to utilize more of the body-wood and the root-wood. In 1757 we find stump-pulling machines described.
In measurement of standing trees the circumference at breast-height was measured with a chain, and for the body-wood when felled the mean diameter was employed.
As regards the felling time, specific advice is found in many forest ordinances which recommend mostly winter felling, stating the proper beginning and end of the season by the phases of the moon, the rule being that all white wood, for example conifers, beech and aspen should be felled on the increase or waxing of the moon; oak, at the waning; but coppice, because it is desired to secure a new growth, at the waxing moon. Prescription was also made sometimes regarding the time by which the removal of the wood from the felling area was to be finished (May to June).
Means of transportation were poor up to the end of the period; snow, as in the United States, was in the Northern country the main reliance for moving the wood. River driving, both with, and without rafts was well organized; various systems of log-slides were developed to a considerable extent; in one place even an iron pipe, 900 feet in length, is reported to have been used in such capacity.
Originally, the consumer cut his own wood, but in the middle of the 17th century special wood-choppers appear to have been employed, for, in 1650, mention is made in Saxony of men, who, under oath to secure honest service, were organized for the exploitation of the different classes of wood. A system of jobbers came into existence about this time, something like the logging bosses in the United States (Holzmeister) who were responsible for the execution of the logging job. The organization of wood-choppers went so far that, in 1718, we find in the Harz mountains mention of an Accident Insurance and Mutual Charity Association among them.
The sale of wood was at first carried on in the house; later it became customary to indicate in the forest the trees to be cut or the area from which they should be cut by the purchaser, and finally they were felled by the employes of the owner. For a long time, persisting into the 18th century, the sale was by area, and this method developed the necessity of surveying; at the same time, however, sales by the tree and by wood measure occurred, but only in the 18th century did the present method of selling wood by measure after felling come into existence. In Prussia, the buyer had to take the risk of felling, and pay, even if the tree proved to be rotten, or broke in the felling. The forest owner seems to have had the whip hand in determining the price one-sidedly, revising, i.e., increasing the toll in longer or shorter intervals. But, in 1713, we find mention of wood-auctions, or at least similar methods of getting the best prices. Finally, special market days for making sales and for designating of wood were instituted; on these days also, all offences against the forest laws were adjudged.
11. Forest Administration
The administration of the different forest properties which the princes had aggregated in the course of time was at first a part of the general administration of the princely property. The requirements in the woods being merely to look after utilization and protection, illiterate underlings (Forstknechte) were sufficient to carry out the police functions, generally under a Forstmeister, or Oberforstmeister, who from time to time would make an inspection tour. Later on, when a more intensive forest management had come into existence, it became customary to call in experienced foresters from outside to make inspections and give advice.
A much more elaborate organization of service is, however, reported in the mining districts of the Harz mountains, in 1547, with the Director of Mines (Berghauptman) at the head, and different grades of officials under him, who were called together periodically for reports and discussions.
Until the middle of the 18th century all those employed in the forest service, at least those in the superior positions, had also duties in connection with the chase, the head official of the hunt being also the head of the forest service; and hunting had usually superior claims to forestry. The men were supposed to be masters of the two branches, i.e., to be familiar with the technique of the hunt and of forestry (Hirschgerecht and Holzgerecht). The higher positions were usually reserved to the nobility until (during the 18th century) the Cameralists came into control of the administration; and with them, under the mercantilistic teachings, the apparatus of officials also increased.
These men usually possessed wide, but not deep knowledge of matters bearing upon their charges. In Prussia, in 1740, the forest service was at least in part combined with the military service, Frederick the Great instituting the corps of riding couriers for the carrying of dispatches who were selected from the forest service, an institution which persists up to date in the corps of Feldjaeger, while the sons of foresters were enlisted in a troop known as Fussjaeger (chasseurs). A new era dates from the middle of the 18th century when the connection with the hunt, the military organization, and the preferred position of the nobility, were at least in part abrogated, and a more technical organization was attempted. The cause for this change was the increase of wood prices, which made a more technical management desirable, and also a decrease in the passion for the hunt. Still, although the forests in Bavaria were declared, in 1780 to 1790, to be of more importance than the hunt, and the two services were distinctly separated, the head of the hunt still ranked above the head of the forest service.
In Prussia, the professional men became early independent and influential, and by 1770, an organization had been perfected which excelled in thoroughness and simplicity. The salaries of the foresters consisted originally mainly in a free house, use of land and pasture rights, their uniform, and incidental emoluments, such as a toll for the designation of timber etc. Later, when everywhere else a regular money management had been introduced, the absence of a cash income and general poverty forced the foresters to steal and extort; and the bad reputation established in the last part of the 18th century, as well as the bad practice, persisted until the 19th century. The lower grades in the service were exceedingly ignorant, and their social position, consequently, very low. Their main business was, indeed, simple, and consisted in the booking of the cut, issuing permits for the removal and the sale of wood, and looking after police functions in the woods. Yet, by 1781, we find regular planting plans submitted in the Prussian administration, and, in 1787, felling plans are on record.
The administration of justice against offenders in the forests was until the end of the 18th century in charge of the head foresters, and only then was transferred to law officers. Theft of wood, as in olden days, was considered as a smaller offense than other thefts, except if it was cut wood. In the beginning of the period, the judge had wide latitude as to amount of the fine to be imposed, but in the 17th century more precise fines were fixed, and in the 18th century, a revision of the fines brought them into proportion with the value of the stolen wood; a choice of punishments by fines, imprisonment or labor in the woods was then also instituted.
12. Forestry Education
The course of education for the foresters until the middle of the 18th century was a simple one and mainly directed to learning the manipulations of the chase, training of dogs, tending of horses, setting of nets, shooting, etc. Two or three years’ life with a practical hunter were followed by journeying and working for different employers, woodlore being picked up by the way from those that knew.
When in the 18th century the need for better woods knowledge became pressing, the few really good forest managers were sought out by the young men who wished to secure this knowledge. In this way, a number of so-called “master-schools” came into existence, each depending on one man. Such a school was that of v. Zanthier in Wernigerode, later transferred to Ilsenburg, started in 1763 and ending with his death in 1778. Theoretical teaching and opportunity for practical demonstration here was such that even students from the Berlin school and men in actual employment attended the courses.
The two great masters and fathers of modern forestry, Hartig and Cotta, each instituted such master-schools, the former in 1789, and the latter in 1785. Cotta’s school was afterwards transferred to Tharandt and became a State institution.
The interest of the State in forestry education found first expression in Prussia in a course of lectures in botany, later also in forest economy, given to the forest officials by Gleditsch, professor of botany at the University of Berlin (1770), to which was added a practicum at Tegel under Burgsdorf, who finally became the head of this mixed State school, and continued in this position until at his death, in 1802, the school was discontinued.
In imitation of this move by Prussia, a military planting school was instituted by Württemberg at Solitude in 1770. The most noteworthy feature of this school, which under various changes lasted less than 25 years, was the course of lectures by Stahl, mentioned before.
Besides this higher school, a lower grade school was started in 1783, but its career was even briefer, not more than ten years.
Bavaria organized a forest school at Munich in 1790 with a four years’ course, and at least three years’ study at this school was required of those seeking employment in the State service; but without having ever flourished, this school, too, collapsed by 1803.
13. Forestry Literature
The oldest forestry literature of this period is contained in the many forest ordinances, which allow us to judge from their prescriptions as to the conditions of the practice in the woods and as to the gradual accumulation of empiric knowledge. Of a forestry science one could hardly speak until an attempt had been made to organize the knowledge thus empirically acquired into a systematic presentation, and this was not done until the middle or last half of the 18th century.
The first attempts at a literary presentation of the empiric knowledge are found in the encyclopædic volumes of the so-called “Hausväter” (household fathers – domestic economists), who treated in a most diffuse manner of agriculture in all its aspects, including silviculture.
A number of these tomes appeared during the 17th century; the best and most influential being published at the very beginning of that century (1595-1609), written by a preacher from Silesia, Johann Colerus, and entitled Oeconomia ruralis et domestica, worin das ampt aller braven Hausväter und Hausmütter begriffen.
Colerus relied upon home experience and not, as Petrus de Crescentiis in his earlier work, Praedium rusticum (translated from the French, in 1592), had done, upon the scholastic expositions of the Italians. He was rewarded by the popularity of his work which went through thirteen editions and became very widely known.
Somewhat earlier, a jurist, Noë Meurer, wrote a book on forest law and hunting (second edition, 1576), which on this field remained long an authority, and gives insight into the condition of forest use at the time.
But the first independent work on forestry, divorced from the hunt and farming, did not appear until 1713, Sylvicultura œconomica, written by the Saxon director of mines, Hans Carl v. Carlowitz.
This book, while containing quaint and amusing ideas, gives many correct rules for silvicultural methods, especially as regards planting and sowing, but the subject of forest management or organization is entirely neglected.
At about the same time (1710) a forest official, v. Göchhausen, published Notabilia venatoris, which, however, contained little more than a description of the species of trees and methods of their utilization.
About the middle of the 18th century great activity began in the literary field. This was carried on by two distinct classes of writers, namely, the empiricists and the cameralists. The former – the holzgerechte Jäger– were the “practical” men of the woods who proved in many directions most unpractical, and exhibited in their writings, outside of the record of their limited experience, the crassest ignorance. The cameralists were educated in law and political economy and, while lacking practical contact with the woodswork, tried to sift and systematize the knowledge of the empiricists, and to secure for it a tangible basis.
Some five or six of the empiricists deserve notice as writers; the first and most noted of them was Doebel (Heinrich Wilhelm) whose book, Jägerpraktica (hunters’ practice), published in 1746, remained an authority until modern times for the part referring to the chase. The author was pre-eminently a hunter, who worked in various capacities in Saxony, a self-taught man with very little knowledge of natural history. Being familiar mainly with broadleaf forest he condemned planting and thinning, but described quite well for his time the methods of survey, subdivision, estimating and measuring, and the methods of selection forest and coppice with standards. His ignorance is characterized by his reference to the “sulphurous and nitric elements of the soil” as cause of spontaneous forest fires.
Opinionated and one-sided, like many so-called practical men, he came into polemic controversies with other practitioners, not less opinionated, among them J. G. Beckmann, who worked in another part of Saxony, where, having to deal with coniferous woods, he had gathered different experiences from those of Doebel. Although he was himself poorly educated, especially in natural sciences, he complained of the ignorance of the foresters, and in his book (Anweisung zu einer pfleglichen Forstwirthschaft, 1759), used for the first time the word Forstwissenschaft (forest science), and insisted upon the necessity of studying nature.
He may be credited with having really advanced forest organization by devising the first good volume division method, and silviculture by advocating the method of clearing followed by sowing.
The first practical forester with a university education was J. J. Büchting, who worked in the Harz mountains. His main interest lay in the direction of survey, division and orderly utilization. He did not, however, make any striking advance, except that he gave equal standing to both planting and sowing.
The two most eminent practitioners of the period, however, active during the middle of the century, were Johann Georg von Langen and his pupil, Hans Dietrich von Zanthier, both of noble family, and better educated than most of their contemporaries, and both engaged in the organization and management of Harz mountain forests, namely, those of the Duke of Brunswick and of the Count of Stolberg-Wernigerode.
The former, without occupying himself directly with literary work, laid down in his expert reports and in his working plans many instructions which form the basis for orderly management and silviculture far ahead of the times. Zanthier, writing considerably (especially Kurzer systematischer Grundriss der praktischen Forstwissenschaft, 1764), is also notable as the founder of the first forestry school (at Wernigerode), 1763.
Another of this class of better educated practitioners, and co-worker with the former two, was von Lassberg, who in 1764-1777 organized the Saxon forests.
An interesting incident in the life of the last three men is their journey to Denmark and Norway, whither they were called to organize the management of the forests connected with the mines.
Another prominent forest manager of the last half of the century, whose literary work is to be found only in various excellent official instructions, among which is one for the teaching of foresters, was the head of the Hessian forest service, a nobleman, v. Berlepsch.
Of the cameralists who helped to make forestry literature, six or seven deserve mention. These, men of education and polyhistors, were either at the head of affairs, or else professors at universities, where they included forestry as one of the branches of political economy.
The credit of the first really systematic presentation of forestry principles and rules, as developed at the time, belongs to Wilhelm Gottfried von Moser, a pupil of von Langen, who served in various principalities, and finally with the Prince of Taxis. In his Principles of Forest Economy, published in 1757, which for the first time brought out the economic importance of the subject, he discusses in two volumes divided into nine chapters the different branches of forestry.
A mining engineer, J. A. Cramer, came next with a very notable book, “Anleitung zum Forstwesen” (1766), which, although not as comprehensive as Moser’s, treats the subject of silviculture very well.
Equal in arrogance and opinionated self-satisfaction to any of the empiricists with whom he frequently crossed swords, was the Brunswick councillor, von Brocke, who, as an amateur, practising forestry on his own estate, developed the characteristic trait of the empiricists, namely, a profound belief in his own infallibility. He produced, besides many polemic writings, in which he charged the whole class of foresters with ignorance, laziness and dishonesty, a magnum opus in four volumes, entitled “True bases of the physical and experimental general science of forestry,” which is an olla podrida of small value.
Less original, but more fair and well informed, a typical representative of the cameralists, was J. F. Stahl, finally head of the forest administration of Württemberg, and at the same time lecturer on mathematics, natural history and forestry at the forest school of Solitude (Stuttgart). Although an amateur in the field of forestry, he was a good teacher and left many valuable and wise prescriptions evolved during his administration.
He compiled in four volumes a dictionary of forest, fish and game practice (Onomatologia forestalis-piscatoria-venatoria, 1772-1781) and founded the first forestry journal.
Since 1770, forestry courses had been given for the cameralists at most of the German universities, and many of the professors prepared textbooks for the purpose. At least three of these professors deserve mention, Beckman, Jung and Trunk.
The first, J. Beckman, professor of political economy at Göttingen, one of the most noted cameralists, was author of a work in forty-five volumes on the Principles of German Agriculture (1769), in which he devotes sixty-one pages to forestry, giving a complete system of forestry, with extracts from all known forestry writings.
J. H. Jung, who gave a special course on forestry at the Kameralschule of Lautern, published a textbook in 1781 in which forest botany was well treated.
J. J. Trunk, who was Oberforstmeister in Austria, as well as professor at Freiburg, was the most prominent of the three, and wrote a comprehensive work full of practical sense (Neues vollständiges Forstlehrbuch oder systematische Grundsätze des Forstrechtes, der Forstpolizei und Forstökonomie, nebst Anhang von ausländischen Holzarten, von Torf und Steinkohlen, 1789).
While at first the ephemeral writings, especially the polemic ones of the empiricists, found room in literary and cameralistic magazines, the need of a professional journal first found expression in 1763, in Stahl’s Allgemeines ökonomisches Forstmagazin, which ran into twelve volumes, and contains many articles important to the history of forestry, and is especially rich in its references to foreign literature.
Two continuations of the magazine under different editorships were of less value. But von Moser’s Forstarchiv, running from 1788 to 1807 with its thirty volumes, is an authority and a historical source of the first rank.
A very characteristic literature of the last half of the 18th century consisted in forest calendars in which advice as to monthly and seasonal procedures in the forest were given, Beckman and Zanthier being among the authors.
