1900 J ENTOMOLOGICAL S0CIET7. 07 



ment in a large orchard which was almost dead from the scale and which the owner re- 

 fused to cut down. It had been sprayed once with pure kerosene, which did some damage 

 and killed many scales, but the owner had allowed it to go without treatment atd the 

 scales had again covered the trees. He sprayed it with crude petroleum obtained in Bal- 

 timore. When he last saw the orchard, in April, the trees were black and greasy, but 

 underneath the bark they were as heelthy as ever, the leaves were coming out in full, and 

 the owner claimed that the crude petroleum had benefited them. He was not recom- 

 mending the oil, but simply giving this as an example. His spraying was done in Feb- 

 ruary and wherever the oil touched the bark it remained dark and greasy for months 

 afterwards. A thorough examination failed to reveal any of the living scales, and he 

 believed that the young scales could not settle and Hve on the oily surface. He felt very 

 much encouraged. It is one of those problems which require co-operative work. As a 

 result of further investigation, he thinks it may become one of the best insecticides ever 

 discovered. He could not think of any better work than trying to find the reasons for 

 the great difference in results in experimental work with insecticides. 



Mr. Webster said he was unable to see what could be gained even if crude petroleum 

 should be perfected. It was true that we will have to get something cheaper and more eflfec- 

 tive than whale-oil soap, which if used on peach trees except during the winter will destroy 

 the fruit, but in view of the difficulty he had had in getting crude petroleum and the 

 high price asked for it, how much better an insecticide than whale oil soap would we 

 have even if it was perfected? He thought that entomologists who carei for thair repu- 

 tation would experiment much and say little for publication, for the present at least He 

 further stated that while experimentation was always in order, it would be best to stick 

 to the whale oil soap until more obscurities in regard to the use cf petroleum had been 

 eliminated. 



Mr. Johnston said he agreed with Mr. Webster. We have got to get 

 something better than kerosene for both peach and plum. In one in- 

 Btacce he had sprayed an orchard of two hundred 9-year old peach 

 trees in February with 25 per cent, kerosene and not a tree was living on the 28th of 

 April last. It seemed to him that atmospheriu conditions were at the bottom of the 

 difficulty, and ha thought it would be necessary to go back to the old whale-oil soap 

 remedy, which destroyed the scale more efl actively and was less liable to injure th-j trees. 

 It would not be wise to substitute crude petroleum for whale-oil soap. After three 

 years experience with the soap, kerosene and gas, he was of the opinion that there are 

 other conditions which must be studied more seriously in the future than in the past, and 

 he heartily agreed in the opinion that co-operation is desirable. He believed it would 

 produce better results in the future. We must not confine our labours to the territorial 

 boundaries of a State, but go outside for information, suggestion? and experiences of 

 others. 



Dr. Fletcher remarked that he was glad to hear what had been said about whale-oil 

 soap and crude petroleum. He had never yet been able to see what object there was in 

 trying to use petroleum. The results were far too conflicting and always unsatisfactory, 

 and the question of cost in the ruin of apparatus was never considered. There was very 

 slight injury to the hose in the use of potash whale oil soaps, which could now be 

 obtained of pretty uniform manufacture and had been giving good results. These are 

 always to be had, and are easy to get in most places, while he had found great difficulty 

 in getting crude petroleum. He thought there was room for experiment with much 

 weaker mixtures of the potash soaps during the summer. His experience was in favour 

 of these soaps in preference to either crude petroleum or kerosene mixed with water. 

 Even with the kerosene emulsion there is sometimes unexpected injury to the trees, 

 which was always put down to difference in the oil or in the water. He was satisfied for 

 the present that the whale-oil soap was the safest remedy, and it was the best for those 

 who are official entomologist .s, who have to recommend formulae to people who will make 

 a mistake if they possibly can. 



Mr. Sanderson related his experience with crude petroleum, which was favourable to 

 its use. He had sprayed a pear orchard on the Delaware river with it in the latter part 

 of January, on a cloudy day, followed by a little hail and rain soon afterwards. Two 

 months later he sprayed another lot of 100 trees with a 25 per cent mixture; it was a 

 very windy day and almost all the trees previously sprayed got a dose of the 25 par cent. 

 7 EN. 



