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THE APPLE SUCKER. 



(Psylla mail, Schmidb.) 



The Apple Sucker is a widespread and abundant insect 

 and is usually regarded as one of the most harmful pests of 

 the apple, both in the British Isles and on the continent 

 of Europe. It has hot, however, been recorded from America, 

 Australia, New Zealand, or South Africa. 



Nature of Injury. Apple Suckers belong to the same 

 Order of insects as Aphides and Capsid bugs, which obtain 

 their food by sucking up the sap of plants through minute 

 holes, or punctures, so causing the injury or death of the 

 parts attacked especially when the latter are in a young 

 growing state. 



In the case of the Apple Sucker, the most serious damage 

 is done to the flower buds and flowers. The insects' when 

 quite young attack the flower buds and later the stems of the 

 blossoms, draining away the sap, with the result that the buds 

 may die unopened, or if they expand, fail to set fruit. In 

 the latter case the trusses of bloom often remain on the tree, 

 dead and brown as if damaged by frost. This is the most 

 characteristic sign of attack. Damage is also done to the 

 developing leaf buds and leaves,; the latter being sometimes 

 deformed, stunted, and rendered light in colour. After the 

 blooming period and when the leavers have reached their full 

 development, further injury is not obvious; but, nevertheless, 

 it seems likely that the trees may be weakened by the attacks 

 of the sucker to the prejudice of the succeeding crop. Certain 

 varieties of apple, such as Bramley's Seedling, appear to 

 suffer less than others, and, in fact, in most varieties there 

 is considerable variation in the precise amount of injury, 

 trusses of bloom noted as being infested sometimes developing 

 a full crop. 



Description and Life-History. The eggs (Fig. ]) of the 

 Apple Sucker are minute, oval, and creamy white in colour, with 

 a small projection at one end and a longer projection, at the 

 other, the latter passing into the bark and holding the egg in 

 position. They are laid mainly on the fruit spurs (Fig. 2), and 

 to a. less extent at the base of the leaf buds and on the twigs 

 generally. The eggs hatch from the end of March to the 

 end of April, varying with the season and also with the 

 variety of apple on which they are laid, those on parly leafing 

 varieties hatching first. The newly-hatched suckers, small 

 rather flat, yellow insects, crawl in between the leaf folds 

 and later into the trusses, puncturing them and feeding on 

 the sap. The young suckers grow rapidly, and before long 

 excrete from the hind end of their bodies a small whitish 

 globule or drop, and later long waxy threads which are usually 



