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The Plum Aphis (4) appears before the buds open, and 

 the parent form may be found in March. They are dull 

 fat purple Insects, while the young are olive green at 

 first, becoming purple later on. The latter attack the 

 young unfolding leaves and soon cause them to curl, 

 not only those of plum and damson, but also allied fruit 

 trees. Spraying should take place as soon as the Aphides 

 are noticed and before the buds are open, if possible, as 

 the Insects are then most readily destroyed. Further 

 spraying late in September and in October helps to kill 

 off the egg-laying females. 



The Woolly Aphis, or American Blight (4) is a univer- 

 sal pest of apple in this country. By constant sucking of 

 the sap it lessens the vitality of the trees; their punctures 

 in the bark and young wood cause abnormal growths of 

 soft tissue which form characteristic rounded swellings. 

 Later on these swellings split and from them arise large 

 rugose deformities often ascribed to " canker." These 

 wounds further predispose the trees to the attacks of fun- 

 gus enemies. Under ground this Insect further causes 

 gall-like swellings on the roots. As a result of Wooly 

 Aphis attacks, young trees may die, stunted trees often 

 result, and the fruit is deficient and of poor quality. The 

 parent wingless Aphides are reddish or purplish-brown, 

 and are invested with a white wooly substance. Living 

 young are produced and become similarly invested with 

 this white material, forming conspicuous objects on the 

 branches of the trees. The wingless egg-laying females 

 and winged males occur in autumn. Each female is very 

 small and lays a single egg near the foot of the tree, 

 and the egg hatches the following spring. Winged 

 parthenogenetic females appear to be rare and are seldom 

 met with. In the winter the Insect lives in the adult 

 state on the bark, or in the roots below ground, and also 

 in the egg stage. The possibility of resistent varieties 

 of apple is worthy of attention, especially as in Australia 

 the roots of apples grafted on to the Northern Spy and 

 Majetin (an English apple) are said to be proof against 

 this Insect. Spraying with soft so-ap and quassia is an 

 efficient summer treatment, but the solution must not be 

 spared, and force is necessary or the wooly covering of 

 the Aphide will not be wetted. The only way of getting 

 rid of the root forms is by injecting bisulphide of carbon. 

 For an average-sized tree four i oz. injections into the 



