300 ON THE DEGENERATION 



len ring of bark. The flagellations which trees some- 

 times undergo to bring down the fruit are injurious to 

 them, by wounding the young branches ; it is so also to 

 the fruit, unless these be of the nut kind : for apples, 

 pears, and olives, when thus brought down, are bruised 

 and very liable to rot. 



Plants often suffer from improper pruning. When a 

 tree is lopped of its branches, they should be cut off ob- 

 liquely ; the sap, when it rises to the wounded part, will 

 then flow down its slanting surface, while, if the amputa- 

 tion be made horizontally, not only will the sap be less 

 able to run off, but the wound will be more exposed to 

 the rain and wind, and putrefaction will probably ensue. 



Emily. I have seen the trunks of old willows, the 

 branches of which are lopped every year, become per- 

 fectly hollow ; which arises, no doubt, from the wood 

 being thus injured. 



Mrs. B. This operation, which is called pollarding a 

 tree, is done with a view of turning the branches to the 

 greatest advantage : in willows, generally, for basket-work ; 

 in other trees, for fuel. When a tree is in the full vigor 

 of life, it will be able to resist such merciless amputation ; 

 but when it becomes aged the wood will not support it 

 without decaying. 



Slight contusions, instead of being prejudicial to plants, 

 produce an excitement which accelerates vegetation. 

 The prick or perforation of insects, which we have no- 

 ticed in the fig-tree, simply occasions a small swelling 

 somewhat analagous to .that produced by a blow given to 

 an animal : in this swelling a minute quantity of sap is 

 deposited, which nourishes more abundantly, and, con- 

 sequently, developes more rapidly, the surrounding parts. 



This leads us to the class of diseases arising from the 

 action of animals on plants. But it is too late to enter 

 upon it to-day : we shall reserve it for our next interview. 



1616. What is said of the flagellations which trees sometimes under- 

 go to bring down the fruit! 1617. When a tree is lopped of its 

 branches, how should they be cut 1 1618. Why should they be cut 

 obliquely! 1619. What is called pollarding a tree, and what is said 

 of it! 1620. What is said of slight contusions upon the bark of trees'? 



