More about Hollow Trees 



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quences are such as might have been expected. We have 

 advanced the opinion that in a great majority of instances, if 

 not in all, the death is caused by electricity. The heart of an 

 oak is very hard, and when protected, may last almost for ever. 

 It has no natural tendency to decay. All decay of wood is 

 consequent on the growth in its substance of fungal parasites, 

 and so long as the bark is whole and the wood living, such 

 parasites cannot easily attack it. Nor does death in itself, if 

 the wood be kept dry, expose it to decay. Witness oak furni- 

 ture, which, if well waxed to keep the weevils out, will last 

 almost like iron. To explain the decay of the middle of an 

 oak tree, we must presuppose the admission of moisture, and 

 in addition usually some damage to its vitality. A lightning 

 stroke may have split the bole from above, and thus admitted 

 the rain, and at the same time it may have passed down the 

 wood and extinguished what little remainder of life such wood 

 may be supposed to have possessed. 



Our next task is to explain the almost invariable presence 

 of a doorway in the hollow tree, by which children, and some- 

 times others, are accustomed to go in and out. The meaning 

 of this doorway is probably thaf at the time the tree was 

 struck, a broad vertical strip of bark was torn off, and that 

 part of the trunk killed on its surface as well as its centre. 

 This surface destruction may involve perhaps a sixth or a 

 fourth of the trunk, and if so, the resulting doorway will be 

 correspondingly wide. The aperture can never close, for the 

 edges can never come together. Thus we see that the 

 existence of a doorway is a strong argument in favour of 

 the lightning hypothesis. It is indeed difficult to explain it 

 on any other. Hollow oak trees without side openings are 

 exceedingly rare. Some firs and pines are very prone to rot 

 in the middle whilst the bark remains sound, but this does 

 not often occur in the oak, if ever. When it happens to 

 a conifer it is always due to some damage to the root, which 

 has admitted the fungus which destroys the wood. From 

 such attacks the oak is probably free. 



