FLOWERS 137 



the leaves are sprayed, to keep these insects and 

 diseases in check. 



The fruits of most plants, like the leaves, need 

 light and air for their best development, and it 

 sometimes happens that the branches of the fruit 

 trees grow so thick that the fruits do not get suffi- 

 cient light and air. This makes it necessary to thin 

 the branches or in other words to prune the tree. 

 Some trees also start more fruit than they can prop- 

 erly feed and as a result the ripened fruits are small 

 and the tree is weakened. This makes it necessary 

 to thin the fruits while they are young and unde- 

 veloped. 



