TRUE-GROWTH. 27 



or about 5,000,000 tons of raw material having to be cut, 

 dressed, transported, converted, and distributed ; and this all 

 means wages that might be earned and circulated here, instead 

 of the money being sent abroad in payment for foreign labour. 



The Growth of a Tree. A tree is a living organism, con- 

 structed mainly of cells and vessels, whose vitality and growth 

 are primarily maintained by the absorption of mineral food 

 through its root-system, and by the ascension of sap to the 

 leaves and its elaboration there, after assimilation of atmospheric 

 carbon -dioxide through the foliage, under the action of sun- 

 light and warmth. 



A tree consists of an overground bole or stem, with large and 

 small branches, twigs, and shoots, bearing the crown of foliage, 

 and an underground root-system consisting of a tap-root or 

 central axis, side-roots, fibrous-roots, and suction-rootlets with 

 one-celled root-hairs for imbibing water and soluble plant-food 

 from the soil. Even in trees with a pronounced tap-root (Oak, 

 Larch, Pine) there is no underground stem before the root- 

 system begins to branch; but the development of the root- 

 system always depends greatly on the physical condition of the 

 soil and on the leaf-area of the crown of foliage. 



A young tree is produced naturally by seed from a parent 

 tree germinating under the influence of warmth, moisture, light, 

 and air. By absorbing moisture its tissue softens and stretches, 

 while the water is partly decomposed and partly used in trans- 

 forming the starch-reserves stored up in it and converting them 

 into grape-sugar (when starch, C 6 H 10 5 , + water , H 9 0, becomes- 

 grape-sugar, C 6 H 12 6 ), by means of which the embryo begins to 

 grow when the weather gets warm enough. 



The embryo grows downwards into the earth by a young root, 

 and upwards into the air by the seed-leaves. The young root 

 lengthens, and through its root -hairs absorbs mineral food, 

 dissolved in the soil-moisture, which is conveyed upwards by 

 the cellular tissue and exposed in the seed-leaves to the action 



