CHAPTER XXXIV. 



THE COMMONER FRUIT PESTS. 



By C. a. W. Duffield, F.E.S. 

 (Lecturer in Agricultural Zoology, South Eastern Agricultural College, Wye, Kent). 



It is essential for the fruit grower to 

 have some knowledge of entomology 

 before he sets out to wage war on the 

 many different insects he is likely to find 

 damaging his fruit. 



Firstly, he should be acquainted with 

 the method of feeding of the particular 

 pest he is out to destroy; secondly, he 

 should know something of the life history 

 and different changes through which 

 insects pass before arriving at the mature 

 stage. Broadly speaking, insect pests are 

 divided into two groups, viz., (1) those 

 provided with mandibles or biting mouths 

 and (2) others whose mouths consist of a 

 longish tube which pierces the plant 

 tissues and enables the creature to suck 

 the juice of the plant. 



Those provided with mandibulate 

 mouth parts devour their food wholesale 

 and may thus be poisoned, but the group 

 with sucking or haustellate mouth parts 

 escape any poisonous substances applied 

 to the outside of the leaves. 



As insects breathe through pores in 

 their bodies we are able to deal with 

 creatures in this second group by suffoca- 

 tion, that is, by applying a wash which 

 will adhere to the body and stop up the 

 breathing pores of the creature. In cases 

 where it is impossible to reach the insect 

 with a wash we must resort to trapping 

 or soil treatment. 



In dealing with injurious insects in this 

 article we will divide them up under 

 headings according to the particular fruit 

 tree they attack. 



Apple. 



Apple Psylla oe Suckbe is often a seri- 

 ous pest. As soon as the buds begin to 

 expand, the minute yellowish eggs which 

 pass the winter on the twigs and at the 

 base of the buds, begin to hatch. They 



find their way to the opening bud, the 

 young, wingless sucker at once commences 

 to suck the sap, thus weakening the growth. 

 In time they mature and become winged, 

 but resort to jumping rather than flying. A 

 heavy dressing of lime and salt wash in 

 February, or lime alone may be used right 

 up to the time the buds are bursting. 

 The eggs are covered up with a coating 

 of lime and so the young are unable to 

 hatch out. Should this not have been 

 done, a nicotine wash used directly the 

 trusses are open will kill the young sucker. 



The Woolly Aphis. — Too well known, 

 especially in old neglected orchards, to 

 need any description. In dealing with it, 

 the fact that it lives also on the roots is 

 apt to be forgotten. When seen on the tree 

 above ground apply with force a spray of 

 Paraffin Jelly, especially on the patches 

 of white wool. At the same time inject 

 carbon disulphide, four injections of 1 oz. 

 each at a distance of one foot from the 

 trunk. Tits do an immense amount of 

 good by destroying this insect in winter. 

 The soft-barked varieties of apple, such as 

 Cox, Ribston and Blenheim, seem to be 

 the most susceptible to woolly aphis. 



Aphides. — We find three othei- species 

 doing damage to apple, the Rosy Aphis, 

 Permanent Apple Aphis, and the Migra- 

 tory Apple Aphis. The first and second 

 hatch out early and feed on the buds as 

 they are developing. We find a second 

 brood about the time the bloom is out. 

 The insects cause the foliage to curl and 

 they live within the curled up leaves. 

 The Rosy Apple Aphis causes reddish 

 blotches to appear on the leaves. The 

 Migratory Aphis lives for a time upon the 

 apple and then flies off to corn and 

 grasses, flying back to the apple in the 

 autumn for the females to lay their eggs. 



