CONFERENCE ON SPRAYING OF FRUIT TREES. 313 



" Spraying as an Insurance." 



Mr. H. F. Getting : I could not refuse the honour of an invitation 

 from the Eoyal Horticultural Society to read a paper on the subject of 

 spraying fruit trees. But after seeing the names of the able scientific 

 men as speakers I feel somewhat diffident in speaking at all, and have 

 devoted a portion of my paper to suggestions and queries, with the object 

 of promoting discussion, which I consider of the greatest importance, 

 especially at a meeting like the present one. 



Each year, as my experience increases, I feel more strongly the . 

 necessity of spraying regularly, not waiting until a severe fungus or insect 

 attack is apparent, but, with very few exceptions, in anticipation — in fact, 

 just in the same way as we insure ourselves or our property against various 

 risks — for it is impossible on a fruit plantation of any size sufficiently care- 

 fully to examine the fruit trees or bushes to see if an attack is present in 

 the early stages. I say this as a general rule, to which there are possibly 

 exceptions. We may, of course, be guided to some extent during pruning 

 by the number of Psylla, or winter moth eggs, or signs of the winter 

 form of scab on the young growths ; but, as a rule, when the attack of an 

 insect or fungus is discovered on the trees by the ordinary fruit grower 

 it is in an advanced stage, which renders it far more difficult, if not 

 impossible, to deal with. For instance, spraying to destroy aphides is 

 generally commenced far too late. 



The plum aphis should be sprayed at least once (better twice) when 

 the bloom buds are swelling, so as to destroy as many of the mother 

 aphides as possible. Each surviving mother aphis may mean many 

 thousands of progeny during the year. A great scientist calculated that 

 the progeny of a single female might in one season amount to close 

 on one million. The apple aphis also should be sprayed before the 

 blossom buds burst. It is money wasted to spray when the leaves are 

 curled, and it is extraordinary how quickly a few aphides cause a leaf 

 to curl. 



Then, again, with apple scab ; unless the trees are sprayed before 

 coming into blossom the chances are very much against effectually 

 checking an attack. 



Apple sucker, or Psylla mali, is a pest that is becoming more 

 troublesome from year to year. I have not been able to find a wash that 

 is really effective against this pest. A fairly strong paraffin and soft-soap 

 emulsion, nicotine wash, and some other washes all kill some, but they 

 leave far too large a proportion alive. One of the principal difficulties 

 with this pest is that in an ordinary season the hatching period is 

 prolonged over several weeks, and I have not yet come across a wash that 

 kills the eggs. 



The question then arises, Is it worth the annual expense of spraying ? 

 My opinion is, under certain conditions, decidedly "Yes." The principal 

 conditions are : — 



1. That the spray fluid must be capable of destroying a large proportion 

 of the insects, or keeping in check the fungus against which it is used. 

 I honestly say I have wasted thousan'ds of gallons of wash on account of 

 its ineffectiveness. 



