xlO THE REPORT OF THE No. 36 



Richmonds begin to show any red; the second about 10 or 13 days later. The 

 mixture we used was 2i/2 to 3 lbs. arsenate of lead to 40 gallons of water, sweetened 

 with nearly one gallon of molasses (black strap). The nozzle on the spray rod was 

 moderately coarse, and care was taken to cover the underside of nearly all the leaves 

 as well as the upper side. We believe in spraying fairly well so that very few leaves 

 are missed, but not in drenching the trees. It takes very little time to cover 100 

 large trees which are close together. The total cost for the mixture, labour and all, 

 is about five cents per tree. 



It was found that, owing to rains, one application was not sufficient in the 

 ordinary season, though it lessened the percentage of wormy fruit greatly. 



Arsenate of lead will, without the molasses, control the pests, but it is advisable 

 to use the molasses, because the flies are very fond of sweet sulbstances. If- the 

 treatment is repeated two years in succession, it should free the orchard for many 

 years, provided there is no nearby infested orchard. Useless cherry trees should 

 be cut down and burned. Neighbors should also be asked to co-operate. 



Tests with Sv^eetened Poisons and with Arsenate of Lead Alone. 



In 1913 an orchard of 183 trees was sprayed twice, June 13th and 23rd, with 

 3 lbs. arsenate of lead to 40 gals, of water, sweetened with 1 gal. molasses. This 

 orchard had been so ibadly infested the previous year that much of the fruit could 

 not be picked. Numerous flies emerged in 1913. In' one cage, 4 x li^ ft, a 

 total of 38 flies emerged from the ground, showing that the infestation was abund- 

 ant. From six trees 175 were captured in between two and three hours by Mr. 

 Spencer and myself. 



Result. — In a little more than a week from the second application very few flies 

 could be seen, and at picking time a crop of $1,000 in value was harvested without 

 either the pickers or ourselves finding a single wormy cherry, though an orchard 

 less than quarter of a mile away under the same kind of cultivation was so badly 

 infested that less than half the crop was harvested. The variety was Montmorency. 



A second orchard on the same farm, consisting of 91 sour cherries planted 

 among plums, peaches and early sweet cherries, had the east half sprayed, the west 

 not sprayed. 



Results. — Unsprayed, 10 to 40 per cent, wormy; sprayed, 1 to 13 per cent. 

 wormy. It was clear that the flies flew about from tree to tree to a greater extent 

 than was usually supposed. 



In 1914 one orchard of 140 late sour cherries was sprayed on June 8th and 

 June 23rd with the same mixture as above. This orchard had been very (badly 

 infested by R. fausia the previous year, and scarcely any cherries picked. It had 

 been well cultivated. Numerous flies emerged and pupse were easy to obtain. 



Results. — The flies were very scarce in about 10 days after the first application, 

 and never became abundant for any length of time. In a sheet spread on June 

 10th under one tree 70 dead flies were captured, most of them in the first 8 days, 

 June 11th to 18th. At the time of picking none of the pickers found any wormy 

 fruit, nor did my assistant. The owner's wife found a very occasional worm when 

 storing the fruit, but so rare that one could not easily state it in terms of per- 

 centum. A few unsprayed trees several hundred yards away had 75 per cent, 

 wormy. 



A second orchard of 180 trees, chiefly Montmorency, received two applications, 

 the first on June 13th, with the same sweetened poison, and the second on June 



