The Stem 



those approaching the centre, they have lost 

 their activity for ever. Their wood is 

 hardened, dried up, encrusted with dead 

 matter. In their old age these interior layers 

 are useless for the work of vegetation. At 

 most by the support of their strong wood 

 they add to the solidity of the edifice. The 

 activity of the tree thus decreases from the 

 surface to the centre. On the surface there 

 are youth, vigour and work ; in the centre, 

 old age, decay and rest. 



ai 



