MANAGEMENT OF SCOTS FIR FORESTS IN NORTH GERMANY. 197 
every tree remaining at the end of that time has had every oppor- 
tunity for full development. The German system, on the other 
hand, results in the survival of the fittest only, and gives no 
artificial aid to individual trees, but allows them to fight it out 
between them. Thus it is that the dominant and vigorous trees 
are the only survivors at the end of the rotation, and these, on an 
average, will not exceed 100 to 150 trees per acre at the end of 100 
years, and the better the soil the smaller the number. A fully 
stocked acre of Scots fir in Scotland will often contain about double 
this number, or between 200 and 300 trees on soil of average 
quality, with an average volume of 25 cubic feet, or 5000 to 7000 
cubic feet per acre. Schwappach, in the work already quoted, 
gives the following figures as the normal yield and dimensions of 
Scots fir in North Germany per acre :!— 
Som I. Quatiry. 
MAIN CROP. | PERropic THINNINGS. 
Average 
fe . ‘ Average | Diameter, | True Cubic | neape | Prue Cubic 
Age. No. of Trees. Height. Breast Contents |No. of Trees. earner 
Height. | 
~ Feet, “Inches. | Cubic Feet. |Cubie Feet. 
20 1716 27 BEY GoM iE Melee, # 
40 704 51 6°50 38572 =| 1012 713 
60 332 70 10°15 5457 | 372 1063 
80 220 84 12°81 6831 | 111 1014 
100 181 91 14°42 7760 39 729 
120 155 102 15°83 8446 25 728 
140 137 106 17:09 9046 1g") 493 | 
These figures tend to show that the final felling is not so heavy 
as might be obtained by earlier thinning ; but the total yield is prob- 
ably as great, if not greater, than that obtained by the British 
system. By reckoning up the total yield of timber from an acre at 
the end of 100 years, we get 11,279 cubic feet from the best quality 
of forest land in North Germany, which is equivalent to 8984 cubic 
feet according to our system of measuring, assuming the latter to 
give 20 per cent. less than the true contents. The number of trees 
standing at the end of this period is 181, which have a total volume 
of 7760 cubic feet true measurement, or an average of 42 feet per 
1 The actual figures are in metres, cubic metres, ete., per hectare, but I 
have reduced them to British equivalents as near as possible. 
