66 PROTECTION OF WOODLANDS. 



in consequence of removal of the layer of dead foliage. Indeed, 

 it is extraordinary with what rapidity an area, hitherto free from 

 weeds on account of the shade in which it stood, is taken 

 possession of when once the area is cleared and laid bare, 

 a phenomenon explained by the extreme lightness of seeds provide^ 

 with feathery crowns and similar means of facilitating transport, 

 by their capacity of retaining their germinative capacity for a long 

 period whilst lying undeveloped on the soil in consequence of the 

 want of a due measure of light and air, and by the carriage of 

 many seeds in the excreta of birds. 



But weeds are not to be met with on every soil to the same 

 extent, or of the same species or energy of growth. The fresher 

 and more powerful (miiierally) any soil is, the greater the quantity 

 of the weeds is likely to be, the more energetic their growth, and 

 the greater their variety ; whilst their appearance on poorer soil is 

 more limited in all these three directions, so that sometimes one 

 single weed (like the heather) asserts itself as the sole or prin- 

 cipal species over extensive areas. The appearance of numerous 

 different varieties of forest weeds can always be regarded as the 

 favourable sign of a better soil, and particularly in regard to its 

 freshness. Climatic conditions also play a not unimportant role 

 in respect to the species of weeds likely to be met with, as the 

 flora of the mountains and higher hills is essentially different from 

 that of the plains and lower uplands. And in the same way the 

 degree of light enjoyed, whether full insolation or merely partial, 

 broken sunshine, is also of essential influence in determining not 

 only the species of weeds, but also the extent to which they 

 occur. Thus, for example, whortleberry thrives best and grows 

 most luxuriantly in a kind of half-shade ; whilst grass, heath* 

 and broom revel in the full enjoyment of light. 



The forest weeds are partially herbaceous, dying off annually 

 as in the case of grasses, epilobium, foxglove, and partially 

 nial, with woody-fibrous stems ; and in this latter case they mi 

 either be plants that creep along the soil, like heath, heather, 

 whortleberry, or else shrubs proper, like hawthorn, dog-wood, 

 similar brushwood. And in the more extended sense, a number 

 quick-growing species of trees, apt to propagate themselves exl 

 sively where not wanted, are also reckoned among the forest we< 

 as, for instance, Aspen and Saugh, or even Birch and Alder ; 

 it seems preferable, and more correct, simply to dub them as soi 



