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or dying trees being always taken first ; each of the remaining compartments is 

 similarly dealt with when its turn to be felled arrives. The quantity of wood to 

 be removed !>y thinnings cannot be prescribed by the working plan, as they must 

 be made to the extent which is judged necessary in order to develop the trees 

 which an- leit. The forester's art is to do this skilfully, and ultimately to remove 

 the old trees in such a manner that they may leave behind them a young self- 

 sown crop to take t>heir place, and so on throughout successive generations. 



For a high forest to be managed under the selection method the arrange- 

 ment is different. Here it is, of course, equally" necessary that all the age-classes 

 should be represented in clue proportion, but instead of the trees or poles of each 

 class being grouped together in separate compartments, all classes are mixed 

 indiscriminately over the entire area of the forest, and there is thus no necessity 

 for the formation of affectations, or compartments, of the kmd just described. 

 After the main features, such as the streams, ridges and roads, have been laid 

 down on the map, the temporary plots, and the descriptions of them are made as 

 before. The forest might in the present case be divided into three sections, the 

 upper of which being on the crest of the hill, is required to be kept as dense as 

 possible, and will not be dealt with in the working plan, as dead or dying trees 

 alone will be. removed from it Suppose that the annual yield of the central 

 section which is 150 acres in extent, has been fixed with reference to the 

 estimated rate of growth and degree of completeness of the stock, at 50 cubic feet 

 per acre, and the trees of marketable girth within it contain on an average 100 

 cubic feet of timber, it follows that the number of such trees which may be 

 removed annually from the section is 1 -^5? == 75. Theoretically this number 



s hould be taken one here and one there over the whole area ; but this would be 

 very inconvenient, so the forest is divided into twelve or any other convenient 

 number of equal or nearly equal blocks, from each of which, in succession, the 

 entire number of trees is to be cut ; after taking windfalls, the choice falls on the 

 ripest trees, those which are dead or dying being selected first. The section 

 below the road is in another zone of vegetation ; it is 100 acres in extent, and its 

 annual yield is calculated at the rate of 60 cubic feet per acre. Suppose, then, 

 that the trees of marketable girth contain on an average 110 cubic feet of timber, 

 the number of such trees to be cut annually i!L?J>? 54. ^ ne sec ti O n will then be 

 divided into blocks, from each of which in succession the entire number of trees is 

 taken. In this manner each zone of altitude may be dealt with on its own 

 merits, while at the same time, the annual fellings being localized, are easy to 

 supeivise, and the wood can be disposed of more readily and more profitably 

 than if the trees had been felled here and there over the entire area. The work- 

 ing plan for a forest under conversion would, of course differ from any of the 

 above ; but this somewhat complicated question will not oe dealt with here. It 

 is only bv an arrangement similar to one of those above briefly sketched that a 

 permanent annual yield of a particular class of produce can be assured, and that 

 the forest can be secured against the risk of gradual extinction. 



A special branch of the forest department is charged with the preparation 

 of working plans, which are not made by the local officers, except in the case of 

 small forests, the plans for which they can frame without interference with their 

 ordinary duties ; but they undertake the revisions, which are made every ten or 

 fifteen years in order to guard against errors, and to allow for changes in the 

 rate of growth, or other causes of disturbance. Pending the preparation of such 

 regular plans the forest department draws up provisional rules, which must 

 accord with local usages, where these are not opposed to the recognized principles 

 of sylviculture. Up to the beginning of 1877 regular working plans had been 



