310 ON THE CULTIVATION OF TREES. 



But it is not only ripening seed, which eventually ex- 

 hausts plants ; all the various diseases we have enumer- 

 ated tend to shorten their existence. 



Emily. Yet those only which attack the wood or bark 

 can prove dangerous to the life of the tree : injury to the 

 other organs, can be of little consequence, since they 

 naturally perish in the autumn. 



Mrs. B. True ; but observe that most of the diseases 

 we have mentioned are of that nature ; the parasites suck 

 up the juices of the stem ; the fungi which adhere to the 

 stem and branches, those which coil round and strangle 

 the roots, all eventually injure the wood. 



There is in the island of Teneriflfe a tree, the Dracrena 

 Draco, of so remarkable a size, that it served to point out 

 the limits of possession of different tribes when the island 

 was first discovered : it has since been repeatedly visited 

 by different travellers, and during several centuries past 

 appears to remain unchanged : it may possibly be of so 

 vigorous a nature as to have existed some thousand years. 



Caroline. And the extraordinary large tree in the Cape 

 Verde islands, Mrs. B., in which Mr. Adamson discov- 

 ered an inscription buried under three hundred layers of 

 wood, must have been of a very great age. 



Mrs. B. From its dimensions and appearance, he cal- 

 culated that it was probably about five thousand years old. 



Caroline. Even allowing for an error of a thousand 

 years or two in his calculation, the tree would still be of 

 a very venerable age. 



And, without going so far for an example, in Blenheim 

 Park there are still in existence old trunks of trees, which 

 are said to have shaded the retreat of the fair Rosamond : 

 and they are supposed to be now not less than a thousand 

 years of age. 



CONVERSATION XXVIII. 



ON THE CULTIVATION OF TREES. 



Mrs. B. Nature has divided the surface of the earth 

 into meadows and forests : in some parts of the globe, these 



1673. What besides ripening the seed exhausts the plant! 1674. 

 Emily thinks the diseases enumerated might not be of essential injury to 

 trees^ except those which attack the wood or bark What is the reply to 

 herl 1675. What is said of a tree of remarkable size in the island of 

 Teneriflfe 1 ? 1676. And of one of the Cape Verde islands'? 1677 -- 

 And of those in Blenheim Parkl 



