36 JOURNAL OF THE ROYAL HORTICULTURAL SOCIETY. 



One of the greatest factors in the control of these pests is their 

 wild food-plants ; clearly it is folly to have, near the orchard, trees on 

 which live insects capable of attacking fruit-trees and which will 

 do so when they are abundant. The Hawthorn, for instance, is a 

 food-plant of the Lappet Moth, Brown-tail, Gold-tail, Lackey, 

 December Moth, Figure of 8, Vapourer, March Moth, Clouded Drab, 

 Ermine (Plum and Cherry species), Apple Aphis, Rosy Apple Aphis, 

 Woolly Aphis, Mussel Scale, Brown Scale, Magpie Moth, Pear Leaf- 

 blister Moth, Early Moth, Shot-borer Beetle, Plum-leaf Saw-fly, 

 Cherry Fruit Moth. That is, twenty-one species that attack fruit- 

 trees feed on Hawthorn. Many of these attack fruit-trees only when 

 abundant on Hawthorn, passing from it to the fruit. 



In an appendix, a list of food-plants tabulates the most important 

 wild trees which are common to our pests. It is desirable, as far as 

 possible, not to grow these as hedges for orchards or quite near to 

 them ; the most important are Hawthorn, Sloe, Willow, Sallow, 

 Poplar, Oak, Cotoneaster, Rose. If one grows ornamental crabs 

 or cherries near an orchard or as part of it they must of course be 

 treated just as the fruit-trees ; so with Hawthorn hedges, they should 

 be treated just as the orchard is, and the pests kept under ; as a rule 

 this is not done because the danger is not recognized. 



9. A Summer Spraying Sequence. — It is perhaps striving for an 

 ideal to suggest a spraying sequence in summer, but already much 

 summer spraying is done for individual pests such as Aphis or Apple- 

 sucker, and the serious fruit-grower would probably do well to try to 

 spray in such a way as to cover as many pests as possible. 



It is a good policy to spray for a pest such as Apple-sucker, when 

 it is serious, without thinking of any other pest ; i.e., if you want to 

 kill Apple-sucker, think of it only, spray with the best thing and at the 

 proper time, and destroy it utterly. So, too, for Woolly Aphis or 

 Mussel Scale. But where an orchard is not suffering from any one 

 pest particularly, can one by summer spraying generally do any 

 good ? 



This depends wholly upon the mixture of trees grown ; where Apple 

 only is grown a sequence is easily arrived at ; where, as in Middlesex, 

 half Plum and half Apple and Pear mixed, with bush fruit, is a common 

 practice, the ideal spraying sequence becomes very difficult. 



I have not a long enough experience of this country to suggest any 

 definite sequence in mixed orchards, but I may offer some ideas which 

 help towards establishing such a sequence. 



For Apple, under the conditions I am familiar with, four sprayings 

 are desirable. 



1. Early spraying with an Apple-sucker wash, which also kills 

 early Aphides. This is usually done in April, perhaps earlier. 



2. Spray with lead chromate as soon as the foliage is formed. 



3. Spray with a contact poison in June ; if Mussel Scale is present 

 use a strong wash and apply to the trunk as well as to the foliage. 



4. Spray again with a strong contact poison in September, for 



