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The Country Gcntlcniaiis Magazine 



has been estimated that ten acres of forest are 

 required for the annual manufacture of i ton 

 of deals, and that if, according to the practice 

 followed in the trade, a tract of forest of 

 200,000 English acres, lying on both sides of 

 a planting, a hundred miles from the sea, be 

 taken on a lease for 50 years, it will yield 

 100,000 trees annually, producing in deals 

 5000 standard, each of 165 cubic feet, or 

 over 4 tons." 



Now, we may reckon that each acre bears 

 30 trees, each capable of producing one-third 

 of a ton of manufactured deals. The follow- 

 ing quotation from Loudon's Arhoretuvi will 

 show that this is at any rate not too low 

 an estimate : — " In an estate (in Norway) 

 l)elonging to Mr White (a London builder 

 who imported his own timber, and furnished 

 Mr Loudon with the details in question) of 

 5600 acres there are 200 acres of naked rock 

 and bogs ; of the remaining 5350 acres one- 

 tenth part consists of the stunted trees already 

 alluded to, or of trees only half-grown. There 

 remain 41 18 acres of thriving wood, all situ- 

 ated on the sides of hills, in narrow valleys, 

 or on plains ; and all the trees are growing 

 close together and sheltered on good soil, the 

 basis of which is the debris of granite rock. 

 On each acre of this good soil there are from 

 320 to 500 trees, of which above 30 in each 

 acre are considered full grown and fit for 

 timber — that is, from 130 to 200 years of age. 

 The diameter of the trunks of these trees, at 

 about I foot from the ground, is from 16 to 

 20 inches, and at from 52 to 63 feet in height 

 from 4 to 6 inches. Thus the average di- 

 mensions of the Scots pine and spruce for 

 timber produced by such an estate are as 

 follows :— Lengdi of the log or tree, 57 feet 

 6 inches; diameter at the lower end, 18 inches, 

 and at the upper end 5 inches. Each log or 

 tree may be sawn up into two deals 9 inches 

 Avide and 3 inches thick, fit for the English 

 market, and two other deals, 8^ wide and \ 

 inch thick, fit for the French market." 



The latter is what is called a batkvi. Deals 

 are no wider, but they are thicker, and 

 as in the above statistics they alone are spe- 

 cified, we shall confine ourselves to them, the 

 smaller pieces being necessary accessories, 



which will not aftect the calculation if allow" 

 ance is made for them on both sides. If we 

 reckon the gradual taper of such a tree as is 

 spoken of by Loudon from 18 inches in 

 diameter at the base to 5 inches at the 57th 

 foot, we shall find it about 8 inches at 48 feet. 

 It will, therefore, give two deals, 48 feet long 

 by 9 wide and 3 thick — or dividing them into 

 12 feet, the itsual length into which deals 

 are cut — we shall have 8 deals out of that 

 tree. Now, 120 deals of that scantling are 

 equal to 5f loads. It would, therefore, take 

 1 5 trees to produce the 5 loads. 



Each load is equal to 50 cubic feet of squared 

 timber, and_,57^ cubic feet of Riga fir are 

 equal to i ton ; so that a ton is about equal 

 to a load and one- sixth, or precisely a load 

 and YTj-ths of a sixth. It will be near enough 

 for our purpose to reckon a load and a ton as 

 synonymous. 



Again, as to the number of such trees 

 which an acre will contain at one time ? 

 Mr White, in the above extract, says 30, and 

 there seems no reason to doubt his esti- 

 mate. Calculation of space gives a ver}- 

 similar result. The above trees to be 18 inches 

 in diameter at the base, and 5 inches in diame- 

 ter at 57 feet high, and to taper gradually to the 

 top at the same rate, should be about 90 feet 

 in total height; and if we allow a space of about 

 a third of their height (say 30 feet) for the dis- 

 tance between the stem of each tree, it will give 

 48 as the number of trees in an acre. But as 

 some deduction must be made on account of 

 those inaccessible tracts from which it is impos- 

 sible to remove the wood, even were it cut down, 

 and on the score of inequality in distribution and 

 condition (it being by no means an unusual 

 thing to find patches of dead and dying trees, 

 we may be pretty sure that we err on the 

 liberal side when v/e allow an average of 30 

 trees per acre. At that rate, if 15 trees make 

 5 loads or tons, an acre will produce 10 tons. 



Applying the figures thus got we find — i. 

 That Norway might cut down 260,000 square 

 acres every year for 100 years without diminish- 

 ing the extent of her forests if she always re- 

 planted what was cut down, and at the end of 

 that period would have her j'early fall of 

 timber always 100 years old; or, turning tlie 



