124 GARDENING DIFFICULTIES SOLVED 



must be thoroughly scrubbed with the mixture. Wear gloves while 

 applying it. Quassia extract, used according to instructions, will 

 kill the green and black aphides. 



Plums Dropping before Ripening 



Q. Many of the Plums on my trees are dropping this season 

 before they are ripe. Can you explain this ] 77. E. E., Maidstone. 



A. The fall of undersized fruits before they commence to colour 

 is generally attributed to overcropping. It may also be due to the 

 blossom being imperfectly fertilised, a condition brought about by 

 the lack of bees or other insects which visit the early flowers. From 

 the sample of soil and subsoil sent, we do not think that this is the 

 cause of failure. We note that the tree was root pruned on one 

 side last autumn ; if the tree has made a good deal of growth since 

 then, we strongly advise you to root prune the other side this autumn 

 and be sure that all large roots are cut, particularly those which go 

 vertically downwards right underneath the base of the tree. Koot 

 pruning will oft-times bring an otherwise barren tree into bearing. 



About Pruning Fruit Trees 



Q. Please tell me why fruit trees cannot be pruned before the 

 leaves fall. Fruit, Bedford. 



A. The reason why fruit trees ought not to be pruned before the 

 foliage falls, is that by early pruning the tree would send out 

 fresh shoots before the autumn had passed. These shoots would be 

 useless as fruit spurs or as flowering wood, as they would be poorly 

 developed and not ripened. Summer pruning consists of stopping 

 the young growths in July. 



Pears in Greenhouse Falling While Small 



Q. The fruits are falling off my Pear trees (in greenhouse) in con- 

 siderable numbers, although they are not half developed. Why is 

 this 1H. E. B., Blackpool. 



A. The fruit is dropping on account of the imperfect fertilisation 

 of the flowers. On cutting you will find that the young fruit is 

 practically seedless. There are various causes accountable for this. 

 Sometimes the pollen on the anthers of the flowers is weak and 

 scanty, and lacking the power to fecundise the stigma. The remedy 

 in this case is artificially to fertilise the flowers by applying the 

 pollen to the stigma by the aid of a camel rhair pencil. Too close 

 and hot an atmosphere at the time the trees are in bloom will have 



