16 



beech, which at present is the tree which greatly predominates. But 

 there are indications that it also may be supplanted. It is a tree 

 more inclined to be exclusive than any other broad-leaved tree ; but it 

 is being encroached upon by the fir. This is attributed by Vaupell 

 to the practice of removing the fallen leaves for bedding for cattle and 

 other purposes. 



"The leaves," says he, "belong to the soil. Without them it cannot 

 preserve its fertility, and cannot famish nutriment to the beech. The trees 

 languish, produce seed incapable of germination and the spontaneous self- 

 sowing, which is an indispensable element in the best systems of sylviculture, 

 fails altogether in the bared and impoverished soil." 



In connection with this he says, 



" The removal of the leaves is injurious to the forest, not only because it 

 retards the growth of trees, but still more because it disqualifies the soil for 

 the production of particular species. When the beech languishes, and the 

 development of its leaves is less vigorous, and its arms less spreading, it 

 becomes unable to resist the encroachments of the fir. The latter tree thrives 

 in an inferior soil, and being no longer stifled by the thick foliage of the 

 beech, it spreads gradually through the wood, while the beech retires before 

 it and gradually perishes." 



And thus Vaupell considers man is unconsciously, and to his own 

 disadvantage, helping forward the encroachment of the Goths and 

 Vandals on the nobler races at present in possession. 



I have had occasion, in the volume cited, to say, " Thus may the 

 succession of firs to beeches, if it should ultimately occur, be satis- 

 factorily accounted for." And in a corresponding way may some of 

 the previous successions of different kinds of trees be accounted for. 

 I say not in the same way, but in some corresponding way ; and in 

 some corresponding way may much of the grass and herbage, which 

 previously covered the forest ground, have given way to the forest trees, 

 not because the conditions were absolutely unfavourable to them, but 

 because being also favourable to the growth of trees, and perhaps 

 comparatively more so, or otherwise simply from their more sturdy con- 

 stitution, these, having gained a footing, maintained it, and the others 

 were overpowered. 



It is interesting, and in some cases advantageous, to read the pre- 

 historic records preserved in nature. And an acquaintance with the 

 natural history of trees found in the Danish bogs may throw light 

 on the gradual progress of the desiccation of these bogs, and on the 

 contemporaneous circumstances in which they existed at successive 

 periods of their history. 



