The Story-Book of the Fields 



So a tree is composed of a succession of 

 ligneous sheaths covering each other. The 

 stem or trunk contains them all, the branches 

 more or fewer, according to their age. Each 

 is produced by the growth of one year. The 

 ligneous sheath of the present year occupies 

 the exterior of the stem, immediately under 

 the bark : those of past years occupy the 

 interior and are nearer the centre, according 

 to their date. The layers of future years 

 will, one by one, be superposed on their elders, 

 and the present surface layer will, in its turn, 

 be imprisoned in the thickness of the trunk. 



Of all these ligneous layers of different 

 ages, the most necessary now is that of the 

 surface. Its destruction would involve the 

 death of the tree ; for it is by its means that 

 the nourishing juices of the earth reach the 

 shoots, the leaves and the young twigs. In 

 their turn, when they occupied the surface, 

 the interior layers acted the same part with 

 regard to the contemporary shoots ; but now 

 that these shoots have become branches, the 

 lower layers only play a subordinate part, or 

 are even absolutely useless. Those nearest to 

 the surface are still capable of some work and 

 assist the layer of the year by bringing the 

 juices of the earth to the branches. As for 



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