THE SAN JOSE SCALE STILL SPREADS 



J. FRED. SMITH, SCALE INSPECTOR, GLAXFORD, OXT. 



THE San Jose scale is slowly but surely 

 spreading from all the old infested 

 spots in Ontario. Only those who have 

 been in close touch, and have taken a keen 

 interest in the spread of the scale, are 

 aware of how far it has spread since the 

 Act was passed in 1898. 



When I was appointed scale inspector in 

 February of that year it was expected by 

 the department that all the scale in the pro- 

 vince would be destroyed and that by pass- 

 ing an Act to prevent trees coming in from 

 the United States we would soon be free 

 from it. Instead, there is more scale in 

 Ontario to-day than ever before. 



It spreads so quietly and insidiously that 

 it may be in an orchard for some time be- 

 fore the owner is aware of its presence. I 

 do not know of a single case where scale 

 has been found in an orchard, and where it 

 was allowed to remain long enough to 

 spread from the original tree, that it has 

 been cleaned out. The reason for this is 

 plain when you are conversant with the way 

 it spreads. Very frequently trees nearest 

 an infected tree are practically free from 

 the pest, while those at a considerable dis- 

 tance are badly infested. It is liable to 

 break out anywhere within a mile of the 

 original infested tree. 



Despite the fact that some of the profes- 

 sors of this province scofifed at my opinion 

 that the principal means of its spreading is 

 by the winged males I still hold firmly to 

 that opinion. These winged males carry 

 the infant ,or larvae, from an infested tree 

 and thus perpetuate the species. Other- 

 wise the scale would be exterminated be- 

 cause the tree would soon die and the death 

 of the scales on it would follow. 



My reason for considering the male 

 scales the chief medium of its spread is the 

 one of choice. Some varieties of trees will 

 stand in the midst of a very badly infested 

 orchard and be almost free from scale, while 



those around it are literally covered with 

 it. I cannot see why some people consider 

 it such a ridiculous idea. Take for in- 

 stance the spread of the codling moth. 

 Every one knows that its spread is by the 

 moth herself, which flies around and de- 

 posits her eggs on the apples, not indis- 

 criminately, but after making a choice. 

 Every orchardist who is at all observant 

 about insects, knows that some varieties of 

 apples never have worms if there are plenty 

 of others to be attacked. The moth dis- 

 tinguishes the varieties when the fruit is so 

 small that we ourselves could not tell what 

 kind it was if we did not see the tree on 

 which it was growing. 



Another reason for thinking the male 

 scale is the culprit has been obtained 

 from information gathered after an 

 infested tree has been planted in an or- 

 chard. I have known cases where the tree 

 had stood for two or three years and then, 

 on becoming aware of the presence of the 

 scale the owner destroyed the tree and 

 there has never been a scale found there 

 since. But I have known other cases 

 where such a tree was left for a time, and 

 just as soon as it became overloaded and a 

 spread was necessary for the perpetuation 

 of the species, the scales could be found not 

 only close by but at a distance. Especially 

 is this so if varieties near are not to its 

 taste. In a district where the scale is bad 

 growers frequently say, " No, you never 

 find much scale on those trees. They do 

 not seem to like them." 



I have said that I do not know of an in- 

 stance where the scale had spread from the 

 original tree or trees, and I wish to empha- 

 size the words " spread from," as there are, 

 I think, somewhere about 100 places in dif- 

 ferent parts of Ontario where the scale was 

 caught in time, and not a scale has ever 

 been found there since. A notable instance 

 of this came under mv observation this 



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