1907 ENTOMOLOGICAL SOCIETY. 19 



Mr. Jarvis : I should like to call the attention of the members to the 

 fact that the 0. _A. College orchard has been- carefully sprayed this year at 

 the proper time in the spring, and twice later on in the season at the usual 

 intervals, and very few, not more than 5 per cent, of the apples are wormy. 

 We have not a full second brood here but have about 15 per cent, of a second 

 brood in ordinary years. A few trees on the campus that were not sprayed 

 had almost every apple wormy. One could scarcely want clearer evidence 

 of the value of spraying. 



The Oyster-Shell Scale or Apple-tree Bark Louse. 



Prof. HuTT was asked by the chairman to open the discussion on this 

 subject. He related his observations in different parts of the province and 

 stated that last year had been a very favorable one for the increase and spread 

 of this scale, and that this year he had heard many reports of its great abund- 

 ance, especially in the counties of Northumberland and Ontario. He thought 

 it was doing a great deal of injury to fruit trees, especially apple trees all 

 over the province 



A Member : Are many other kinds of trees attacked by this scale besides 

 apple trees? 



Mr. Jarvis : We have found it at Guelph on apple, pear, plum and 

 cherry trees; on currant, gooseberry, rose, spireas and lilac, and also on 

 numerous forest and shade trees, such as mountain ash, hawthorn, red-osier, 

 dogwood, basswood, both black and white ash, American aspen, horse-chest- 

 nut and mulberry trees. 



Mr. Caesar : I think that from what I have seen this year there will 

 not be half the number of Oyster-shell scales next year that there were last. 

 The scale-lice hatched out all right this June and the branches of many trees 

 were almost covered with the young. I examined some of these^same trees 

 a few weeks ago and found that the great majority of the young scales had 

 not lived through the season, but had died when only a few weeks old. 



Dr. Bethune : Some experiments that have been made with lime- 

 sulphur wash seemed to show that it is not entirely satisfactory as a remedy 

 for this scale, though it destroys a large number of them. 



Dr. Fletcher : It is not usually considered a perfect remedy for Oyster- 

 shell scale. 



Mr. Crow^ : I sprayed a few trees here with the ordinary kerosene emul- 

 sion, and some others with the flour-kerosene mixture. The spraying was 

 done just when the young had hatched out and were moving over the 

 branches. The results were very satisfactory. I can bear out the state- 

 ments made as to the prevalence of this scale throughout the province and 

 the vast injury it is doing, but I agree with Mr. Caesar that from some cause, 

 whether it be the late spring and cold weather after the young emerged, or 

 whether it was owing to rains at that time, there seems to have been a very 

 great diminution in the number of living scales this fall. 



Mr. Nash : My experience makes me agree with what has been said in 

 regard to the decrease this year in the number of scales. This spring I 

 noticed one of my trees late in June swarming with young scales. 1 examin- 

 ed the same tree not long ago and was amazed to find scarcely a living scale 

 on it. 



Dr. Fletcher : This is not the case in all parts of the province. I was 

 interested in Mr. Crow's remarks about the success of the kerosene emulsion 

 and flour-kerosene sprays. These may be considered the standard remedies 

 against the Oyster-shell scale. 



