714 Orchard and Bush Fruit Pests. [march, 



terus arundinis, and I feel certajn that the two are the same, 

 just as the spruce gall aphis and larch aphis are the same 

 species. At least I can detect no structural difference, and 

 specimens have developed when transferred from prunes to 

 rushes. 



Hop-Damson Aphis. — The third prune aphis is the hop- 

 damson aphis {Phorodon humiili)^ which occurs on damsons and 

 wild prunes in the egg stage in winter, and in the adult stage in 

 spring. From all hop-growing districts this aphis has been 

 reported as abnormally abundant. It is now well known by all 

 hop-growers and fruit-growers that it migrates to the hops from 

 damsons, &c., and becomes the hop louse. Usually there is one 

 main migration from the middle of May to the second week 

 in June, and the damsons are then cleared. Last year they 

 stuck to the damsons right through the summer, and irregular 

 migrations at no definite time took place late into the summer. 

 It is important to deal with this aphis on the damsons by 

 timely spraying. This must be done later than for the " leaf- 

 curler," and earlier than for the " mealy aphis " which has also 

 been seen during the past year on damsons — an unusual occur- 

 rence. Even then we have to fight against the broods migrating 

 from wild prunes to the hops, and this we cannot hope to do suc- 

 cessfully. This aphis does much damage in damson plantations. 



Currant Blister Aphis. — Currants have been less severely 

 attacked than usual, but the currant blister aphis {Rhopalosiphum 

 ribis) has been found destructive in one or two Kent plantations 

 during the year, and also in Worcestershire and North Devon. 



Apple Aphides. — The apple aphides were less annoying than 

 usual in Kent, but a very bad attack of the apple leaf-curler 

 {Aphis pomi) occurred throughout Worcestershire and to some 

 extent in Herefordshire. In Devonshire it appeared to have 

 been less virulent than usual Great numbers of the back eggs 

 of Aphis ponii have been laid this year in Kent. Twigs sent 

 have been often completely covered with the ova. This usally 

 precedes a bad attack in the following year. It is thus very 

 important to have all prunings burnt. 



The stem apple aphis [Aphis fitchii) was reported again from 

 Kent, and it is now certain that this migrates to corn and 

 grasses on leaving the apples. 



