ARBORICULTURE. 361 



elevation are the pine and the birch, (these also it may be 

 observed will flourish in the lowest situations, the birch in 

 particular will grow in soils periodically overflowed or covered 

 with water for two or three months in a year). The highest 

 altitude of the growth of the pine is stated to be from twelve 

 thousand to fifteen thousand feet above the level of the sea, in 

 latitude 20 ; and the limits of the growth of the oak appears to 

 be confined to ten thousand three hundred. The last species of 

 trees found nearest to the limits of perpetual snow on Mount 

 Caucasus, in latitude 42 30', and on the Pyrenees, are the 

 common birch (Betula alba), and the hooked pine {Pinus 

 uncinata), and the red spruce fir (Pinus rubra). On the Alps, 

 latitude from 45 to 46, the common spruce appears limited to 

 an elevation of about five thousand nine hundred feet. In 

 Lapland the birch is found at the altitude of one thousand six 

 hundred feet in latitude 67 and 70. 



The influence of different altitudes on the distribution and 

 growth of forest trees, is evident even in the inferior elevations of 

 the forests of Britain. The pine, fir and birch occupy the 

 highest points ; next the sycamore and mountain elm ; lastly, the 

 oak, beech, poplar, ash and chesnut. When the ground to be 

 planted is, therefore, so high above the level of the sea, as to 

 influence materially the nature of the climate, the forest trees to 

 be planted should be selected according to the above principles. 

 In practice this may be termed region planting. By imitating 

 the natural process in this respect, not only the most profitable 

 returns which the site and soil are capable of producing will be 

 secured, but also the most ornamental effects produced on the 

 landscape, and the useful ones of judicious shelter obtained. It 

 generally happens in extensive planting that the soil varies in 

 different parts of the site in its properties and fitness to rear one 

 species of tree better than another. When these different soils 

 are, therefore, planted with the different trees best adapted to 

 each, masses of diversified outline will adorn the landscape, 

 having all the effect of a tasteful design, and the trees will be 

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