A Brief History of Forestry.. Fernow Bernhard Eduard

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СКАЧАТЬ 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, СКАЧАТЬ