PURE FORESTS AND MIXED FORESTS. 19 



sumption of paper, the use of wood to make paper-pulp will entail 

 the rapid destruction of forests. Nothing of the kind. The 

 paper-pulp manufacturer is a most powerful ally of the forester. 

 The small stuff in spruce woods can always be sold, and hence 

 the forester can thin regularly and frequently, as he is sure of a 

 market for his thinnings. In this way this huge quantity, which 

 amounted to 53,000,000 cubic feet, was sold without difficulty. 

 When all the timber had been disposed of, there remained the 

 task of replanting the area, and this also has been accomplished 

 successfully. All this required systematic and methodical arrange- 

 ments. The heads of the Bavarian State forests determined to 

 diminish the cuttings in other forests, so as to throw the demand 

 for timber more upon those which had been devastated by the Nun. 



You will now understand the great risk to which pure Spruce 

 forests may at any time be exposed. There were beech trees here 

 and there, which had grown up with the spruce, and the cater- 

 pillars had not touched them. The Nun had destroyed many 

 other forests, and it was found that mixed woods, where the 

 spruce was associated with beech in large quantities, or with 

 Scots pine, had not been attacked by the insect. 



I could give you many other instances of large areas stocked 

 with pure woods, but I believe you understand now what the 

 advantages and what the disadvantages are of pure forests. The 

 advantages are that the management is simple and easy, for you 

 have to deal with one species only. The disadvantages are that 

 pure woods are more exposed to damage by wind and snow, by 

 fungus, and by insects. The tendency therefore, you may readily 

 imagine, in Germany at the present day is towards mixed forests. 



Some of the finest mixed woods are those of Scots pine and 

 beech, the beech forming the lower story and the Scots pine the 

 upper story. Other woods consist of oak and beech, the beech 

 again forming the lower story and the oak the upper story of the 

 wood. Trees have to be studied with reference to the amount of 

 light they require, and the finest mixed forests are those where 

 you have a tree that requires much light forming the upper story 

 — standards, you may call them — and a tree that requires less 

 light in the lower story. You all know that the Scots pine 

 requires a great deal of light. It does not grow up in the shade 

 nor does the oak. 



You also know that young thickets of Scots pine and young 

 thickets of oak shade the ground well. The surface soil under 



