2136 ARBORETUM AND FRUTICETUM. PART III. 



suckers, are consequently killed m toto ; while the oak, now sole possessor 

 of the soil, starts up and grows vigorously. On the other hand, land which 

 has been solely occupied by oaks previously to its cultivation, is invariably of 

 a superior quality to what is termed pine land ; and is naturally a longer 

 period under cultivation before it is turned out, by which means the roots 

 of the oaks are completely eradicated. The pine seeds, being winged, and 

 thereby easily carried by the wind to a considerable distance, if the ground 

 is free from the roots of other trees, are the first to establish themselves ; 

 and, being of a free and rapid growth, they take the lead of all other species 

 of timber, and become the principal occupiers of the land : but when the 

 roots of the oaks are not destroyed, they will take the lead, and resist the 

 pine and other trees. All pine lands, which originally had no oaks, will 

 invariably produce pines again, whether they have been under cultivation for 

 a long time or a short period." (Gard. Mag., vol. viii. p. 287.) In the north 

 of Europe, including the Highlands of Scotland, a pine forest, unless it has 

 been cleared, and the soil brought under the plough, or laid down in 

 pasture, continues such for ever ; the seeds of the older trees coming up in 

 the open spaces, as thick as in the nurserymen's seed-beds. 



Accidents. With reference to the goodness and value of the timber, the 

 most injurious accident that can befall a pine or fir tree is to have the dead 

 stumps of the side branches left on, whether through neglect in artificial 

 plantations, or from the trees not being sufficiently close together in natural 

 ones. In such cases, the dead stump is buried under the living wood ; and, 

 when the tree is sawn up into boards, every point where these stumps 

 intersect the board forms a knot, which, if not glued in, generally drops out, 

 leaving a hole through the board. The pine and fir tribe, from their resinous 

 nature (resin being a powerful non-conductor), are said to be less liable to 

 be struck by lightning than broad-leaved trees ; and hence they are con- 

 sidered as particularly suitable for growing on mountains. (See Nuttall in Gar- 

 dener's Magazine, vol. xiii. p. 351.) As, when standing singly, their spiry 

 tops do not oppose so large a surface to the wind as those of round-headed 

 trees, and as their narrow leaves offer very little resistance, they are not 

 so liable to be blown down by high winds as might be imagined from their 

 comparatively small roots ; and they are still less so when associated toge- 

 ther in dense masses of plantation or forest. As forests of the pine and fir 

 tribe are generally situated on hills or mountains, and for the most part 

 in climates where they are subject to be covered with snow for several 

 months in the year, they are very liable to what may be called geological 

 and meteorological accidents. In Switzerland, those movements of rocks, 

 stones, and soil which take place in the mountainous districts, more or lesj 

 every spring, and are called eboulemeus, often destroy several acres of pine 

 forests at a time. In scattered forests, the snow falling on the trees 

 individually is retained by their branches, and, when these are of great 

 length, often weighs them down, and breaks them; while those move- 

 ments of snow known by the name of avalanches are sometimes as injuri- 

 ous as the eboulemens. We have seldom been more gratified with winter 

 scenery, than when passing through a spruce fir forest in Sweden. We 

 have seen trees of all ages grouped and distributed in innumerable ways ; 

 here weighed down with snow, and there boldly shooting through it their 

 vivid green pyramidal heads. When a sudden thaw takes place in spring, the 

 snow and the branches seem all in motion ; some branches, being relieved 

 from their load of snow, are rising up in consequence of their elasticity ; 

 and others, from the snow falling on them from branches still higher up the 

 tree, are bending, and perhaps breaking, under the additional weight. In the 

 pine and fir forests of Europe, a number of branches, and also of entire trees, 

 are damaged in this way every year ; but this is nothing to the havock which 

 takes place in America, during what is called an " ice storm." In the Magazine 

 of Natural History (vol. vi. p. 100.), a very striking description of one of 

 these storms at Philipsburg, near the Alleghany Mountains, is given by H. (' 



