No. 4.] SHADE-TREE INSECT PROBLEM. 117 



wo followed his directions and the result was satisfactory. 

 I omitted one part of nij little talk about the use of kero- 

 sene emulsion. I spoke of simply using it on the trees. 

 Instead of resorting to hot water, as suggested by my friend 

 from Northampton, we sprinkled the trunks and around the 

 roots of the trees with kerosene emulsion. I think that is 

 easier than to try to keep water hot. 



Mr. Clark. I would answer that by saying I have ex- 

 perimented upon the larva? and pupa? with both, and it was 

 found the hot water was more effective. The other is good, 

 there is no question about its being very good indeed, but 

 when you put on the hot water there is no possible escape. 

 When you put on the boiling hot water, everything is gone 

 as far as life is concerned. The hot water costs nothing, 

 and the kerosene emulsion costs considerable. 



Mr. Draper. It is not the purpose of the speaker to ad- 

 vertise airybody's goods or to advertise Mr. Ware's pump, 

 but that is, in my judgment, the best equipment for our 

 park and street work. You are obliged to have your ladder 

 men as well as the tree men, that we call " squirrels." You 

 have to have the ladder men, and they can just as well work 

 the pump, and one of these pumps will run four lines of hose 

 on most of your trees, and that is about as fast as you can do 

 it. I don't believe it is policy to go into the steam pumps. 



One word more. Our experience in making arsenate of 

 lead was fairly satisfactory. We took the formula from Mr. 

 F. J. Smith of the gypsy moth committee and tried to make 

 it ourselves, and it was fairly satisfactory. But when Mr. 

 Kirkland went into this company and they put out a mate- 

 rial that all we had to do was to put it into the tank all 

 ready mixed, I thought they were doing a great service to 

 those fighting the insect pests, and I use that chemical as 

 furnished by them, and it has been entirely satisfactory to 

 us the past year. 



The Chairmax. It seems to me it demands a little 

 explanation as to the Ware pump and the arsenate of lead. 

 The committee who had charge of the gypsy moth work 

 felt the necessity of a better insecticide than Paris green, 

 because of the danger of burning the foliage, and the 



