198 TRANSACTIONS OF ROYAL SCOTTISH ARBORICULTURAL SOCIETY. 



and a distinct general type is not very pronounced. As a matter 

 of fact, in low-lying stretches of country with a comparatively 

 mild climate, where the pine has no vicissitudes to contend 

 against, the general character is a broad and branchy crown, but 

 other types are formed by more or less local conditions. The 

 type in such localises is not constant. 



When we go farther north, or higher up in the mountains, where 

 the climate is rougher and where the pines have to resist the 

 inclemency of the weather, the crowns assume more and more the 

 spruce-like shape, with comparatively thin branches and short 

 leaves ; and the stems are straight. They form a distinct racial 

 type. 



The reason for the establishment of different types is, as already 

 pointed out, a question of propagation by selection. Where 

 pines grow up in an intermixture with young beech, the branchy, 

 broad-crowned kind has, as already stated, the best chance ; and 

 even, barring the forester's assistance in favour of its more valuable 

 comrades, or an accidental break in the young beech canopy, this 

 kind only has a chance of reaching maturity and propagating itself. 

 Hence the ill-shaped, branchy, but undoubtedly sturdy tree takes 

 unaided possession of this field from generation to generation, often 

 at the cost of the beech. Even in pure pine forests the branchy 

 kind has a tendency to suppress its weaker neighbours, unless 

 restricted by the forester's interference. On the other hand, when 

 the stout branches, the broad spread of the crown and the long 

 leaves represent a danger to the prosperity or existence of the 

 pine forests, these types have disappeared in the course of 

 generations. 



Dr Kienitz considers annually recurring heavy snowfall to be 

 the main cause of the formation of the racial type in the rougher 

 climate, in more northern latitudes and at higher elevations. He 

 had the opportunity of observing in Brandenburg the effect which 

 two, for the locality, exceptionally heavy snowfalls had on the 

 broad-branched type of pines. Both young and old trees of the 

 branchy kind were heavily damaged, broken and bent to such an 

 extent that large numbers had to be removed, whereas those of the 

 slender type remained unharmed. The pictures taken in Chorin 

 show the varying effects of the snow. Figure 5, which was 

 taken in the Bavarian Highlands when the remains of the winter 

 snow still adhered to the branches, gives some idea of the weight 

 which trees of the spruce type can bear without breaking. It is 



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