General 



So also with the thorny thickets of sloe, blackthorn 

 and hawthorn, through which the young trees have to 

 force their way upwards to the light. One might com- 

 pare them to the sticky bud scales of a horse-chestnut 

 shoot which guard the young and green leaf rudiments 

 from fungi and insect pests. 



Such a thicket would keep out roe and red deer or 

 cattle, and so give some chance for the quick growth 

 of ashes and birches and the slower and more sturdy 

 development Of young oak trees. 



So soon as the forest trees grow up and overshade 

 the thorny rosaceous shrubs, these latter die away, 

 but their life work is not wasted. Everything that they 

 have made, every particle of carbonic acid or of nitrate 

 used by them is returned to the soil, and is used again 

 by the higher form of vegetation. 



In this connection the higher plant is both the taller 

 and also the more complex. An oak or beech is of 

 much more importance to the world than a hawthorn. 



Every green plant growing in such a wood, even the 

 algae which form the green stain upon the bark, the 

 ferns, mosses, and undergrowth is of use. For its waste 

 products are returned to the soil, and form part of the 

 regular annual manuring of leaf mould. 



The best authorities in forestry are careful to warn 

 planters of the danger of taking away from the forest even, 

 for instance, the apparently useless ferns and bracken. If 

 this is permitted the soil must be impoverished. The most 

 pernicious of all customs is that of collecting the dead 

 leaves and actually burning them, and yet this wanton 

 waste of the richest manure is by no means unusual. 



Just as, or even more, important is the part played in 

 the growth of a wood by the fungi, bacteria, and various 

 insects and other small animals. 



Many of these are kept by the forest ; there is a 



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