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on the underside, and suck the sap. The leaves in consequence 

 become sickly and show a more or less marked change of 

 colour, turning first yellow and then in a bad attack 

 greyish white. In the latter case the leaves die and the fruit is 

 unable to mature. Gooseberries suffer chiefly in the spring 

 and early summer, but attacks on plums and apples occur 

 later, often towards the end of the growing season, when pre- 

 mature leaf-fall may be caused. In these cases the leaves 

 sometimes take on a rusty colour instead of yellow. Green- 

 house plants may suffer at any time when in leaf. Dry condi- 

 tions are likely to cause attack both under glass and outside. 



Description and Life-History.- Bed Spiders themselves 

 are little red creatures, considerably smaller than the head 

 of the average pin. When adult they have four pairs of legs, 

 a short rounded body and a mouth formed for biting and 

 sucking. The Eed Spiders of apples and other " top " fruit 

 spend the winter in the egg stage, the eggs brilliant crimson 

 in colour being often crowded together on the twigs. These 

 eggs hatch in early spring and the mites feed and breed 

 throughout the summer in the leaves, eggs again being laid 

 on the twigs in or before autumn. 



The Gooseberry Eed Spider seems to be less definite in its 

 mode of spending the winter. Doubtless a number pass 

 through in the egg stage but others hatch earlier, and both 

 eggs and mites may be found on the bushes in winter. In any 

 case the mites have left the eggs by the time the buds unfold 

 and they feed and breed in the foliage. As a rule their activity 

 does not extend beyond midsummer. 



The Greenhouse Eed Spiders and the Hop Eed Spiders, 

 differ from those mentioned above in that they spin chiefly 

 on the undersides of the leaves fairly thick silken webs 

 among which they live and lay their eggs. They spend the 

 winter partly in the egg stage but also largely as young mites 

 which shelter in crevices of the bark of vines and other fruit 

 trees, in cracks in woodwork, or in the case of hops on the 

 poles, on trees, or under stones and clods. 



Methods of Control. (I) Spraying. lied Spiders on fruit 

 trees are controllable by spraying, but as in the case of almost 

 every pest the work must not be put off too long or the damage 

 will already be past repair. Never should the foliage be 

 allowed to turn to the silvery-grey colour before the work 

 is put in hand. In the case of gooseberries a tendency in 

 spring to lose a healthy green colour should be regarded with 

 suspicion and leaves should be examined with a magnifying 

 glass in order to see if Eed Spiders are present. An in- 

 expensive glass is quite good enough for the purpose and 

 will have many other uses in the control of pests. Spraying 

 when necessary must be thorough so that the leaves are 

 thoroughly wetted. 



