382 



Insect Pests. 



FIG. 254. — Aphis pruni. 

 Second generation (viviparous female) 



by the male, deposits little shiny black eggs at the base of the buds 

 and on the twigs. Egg-laying may commence early in October and 

 goes on till November. These eggs usu- 

 ally hatch early in April, but I have 

 observed the lice in March. 



Besides prunes this aphis is also found 

 on peach, nectarine and apple, but I have 

 not seen it breeding on those plants. 



I am inclined to believe it flies to 

 umbelliferous plants (3) and breeds there. 

 An allied species, A. iwunifolia, is shown 

 (Fig. 252 B). 



Prevention and Teeat:\ient. 



This pest can easily be kept in hand 

 if attacked in its early stages, but when 

 once the females have set to work to 

 produce those countless living young 

 and they curl up the leaves it is most 



difficult to destroy the pest, for not only are they protected by the 



curled leaf, but also by the honeydew and meal which help to repel 



the insecticide. 



Washing should start before the blossom buds open, so as to 



destroy the mother-queen before she 



produces her green young. In any 



case it should never be later than the 



date of falling of the blossom ; up to 



this time some good will be done. 



The object should be, however, to kill 



the mother-queens before the blossom 



appears. 



Considerable benefit has been found 



from lime wash, salt and waterglass 



heavily sprayed over the plums and 



damsons just before the buds burst. 



The eggs are laid in crevices, bud 



groups, etc., where the lime wash col- 

 lects, and very many are thus prevented 



from hatching. The writer has seen 



trees completely clear of the Aphis 



pruni and the Fhorodon ImmuJi (Hop- 

 Damson Aphis) by this treatment, and it cannot be too strongly 



FIG. 255.— MOTHER-QUEEN OF PLUM 

 APHIS IN AXIL OF BUD. 



(Huch enlarged.) 



