1918 ENTOMOLOG ICAL SOCIETY. 83 



The sulphur dust, however, without any poison in it gets over this difficulty, because 

 it does not stain anything. It may, therefore, be applied even a day or two before 

 picking and unless followed by prolonged heavy showers will protect the fruit until 

 it is marketed. 



Having thought of this plan we tested it out on the above-mentioned sweet 

 cherry orchards. The fruit was kept clean up to a few days before picking — in one 

 orchard by three well-timed applications of liquid lime-sulphur and in the other 

 by two of these and one dusting. These were followed in both orchards by a 

 thorough dusting one or two days before picking. As a result in one orchard there 

 was less than 1 per cent, of rotten fruit, in fact my assistant placed it at 1/10 of 

 1 per cent., though a large check tree in a more exposed situation had over 80 per 

 <3ent. of infected cherries. Moreover, in spite of the weather this year being very 

 favourable for rot and causing great losses to cherry growers, the owner told me 

 that this was the first time in many years he had been able to harvest the fruit off 

 several of the trees that were specially susceptible to the disease. 



The other orchard was a little later in maturing its fruit and was subjected to 

 several very heavy rains before it was all picked. These washed the sulphur off the 

 later fruit. Nevertheless all the earlier varieties yielded a very clean crop and 

 it was only on the later varieties that any appreciable amount of loss occurred, 

 though even here there was not much loss. iVn extra dusting of these trees would 

 liave prevented this. 



Since the Brown Eot of cherries attacks also plums, it is clear that the same 

 plan could be used of protecting varieties very subject to this disease. 



It takes so few minutes to dust 100 cherry trees that a dozen fruit growers 

 •could purchase a duster among them and thus make the cost to each very little. 

 The cost of the material, namely, sulphur with ground talc as a filler, in normal 

 times would be $3.00 or less per 100 pounds, which is less than half the cost when 

 arsenate of lead is added to the sulphur, so that the material would not be very 

 expensive. We feel that the adoption of this method of preventing rot would mean 

 the saving of many thousands of dollars annually to growers of stone fruits. 



Father Leopold: Have you tried dusting for the control of scab of pears? 



Prof. Caesar : We did not try ^dusting on any variety of pears subject to 

 i?cab, and I cannot speak regarding that. 



Father Leopold: This year for the first time we have sprayed oiir 05 acres 

 of orchard by dusting instead of with liquid spray. The liquid spray machine 

 we had before was burnt in the fire. For apples we had a marvellous success 

 all along, but we had the worst and most scabby pears I have ever seen in my 

 life. We had good success last year on pears with lime-sulphur wash. I think 

 the leaves are so glossy that the dust will not stay on, and of course this applies 

 to the fruit also. The leaves and fruit of 'the apple tree are more hairy, and 

 the dust will stick on better. I may say that we had 85 per cent, clean fruit 

 in the 65 acres of orchard, but the Macintosh was especially good — 95 per cent, 

 clean. We had a loss with Wealthy because they were not properly sprayed. 

 None of the Wealthy apples ever had scab before, but of course this has been an 

 exceptionally bad year. With regard to Codling Moth, wherever two sprays were 

 applied we had very good success. Last year we had over 35 per cent. Codling 

 Moth in our orchard, but this year the orchard was clean and free from Codling 

 Moth to the extent of 90 per cent. We made no liquid sprays at all this season. 



Mr. Fetch : With regard to the value of spraying against dusting, I do 

 not tliink it matters very much which you use so long as it is done thoroughly 

 and' repeatedly. This year was a very bad year for scab and we dusted and 



