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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. fades 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 soap 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 
