1917 EXTOMOLOGICAL SOCIETY. 33 



drive the dust dowu and not permit it to reach tiie top of the tree. The ideal con- 

 dition is a perfectly calm day, or one with almost no breeze. The driver should 

 go up and down the rows parallel with the wind so that the operator may shoot 

 the spray into the trees at light angles to the row, thus finishing the v/hole orchard 

 as he goes. It. will not do to dust one side of the trees; both^must be done just as 

 in the case of the liquid spray ; otherwise the results will not be satisfactory. Some- 

 times, especially at the Codling ^loth spray, it is impossible to watch for an ideal 

 day, and one has to spray with the wind. .Then if it does not change soon, the 

 remainder of the tree can be sprayed by blowing, the dust in from each side at right 

 angles to the wind. The spraying may be done in the morning or evening when the 

 wind usually moderates. 



It is just possible that grapes in the earlier dustings before the leaves are 

 large and abundant could be dusted against the wind so that the dust would be 

 blown back to the opposite side of the next row, in this way covering both sides 

 and saving time and labor. This cannot be done, however, when the foliage is 

 dense. 



Dusting apparently may be done with safety* either when the foliage is dry 

 or moist. 



Amount of jMaterial Required Per Tree. 



For very large apple trees requiring about 12 gals, per tree of liquid for the 

 Codling Moth spray, I use aij average of nearly 4 lbs., but found that 3 lbs. would, 

 if properly applied, suffice. For an average size apple tree about 25 years of age, I 

 should use at least 2 lbs. Plum, cherry and peach trees require anywliere from 

 about 1/4 to 2 lbs. per tree. It requires a good deal of careful watchfulness to deter- 

 mine how much to use. A careless man may use 100 lbs. in a few minutes, where 

 one-quarter the amount would have been sufficient. 



Need of Care i^i Aitlyixg the Dust. 



I found that to cover either a large or small tree thoroughly witli tl.e minimum 

 loss of material required much quickness of movement and constant watchfulness. 

 It is no job for a lazy or an indifferent man. As a rule the best method was to move 

 the outlet pipe up and down quickly, and not to drive so close to the tree that the 

 branches would be in the way. This, however, often had ix) he varied for a sudden 

 gust of wind from time to time would carry the dust away from the desired 

 direction. This necessitated a different stroke to cover the missed area. Sometimes 

 too, the branches were too close' to spray them except by shooting the dust back 

 quickly when the wagon had passed. One would be very tired after a hard day of 

 careful dusting of large trees. 



There is very little danger to the operator from the dust, but it is expedient 

 to use goggles. 



CoMPARisox OF Time Required for Dustixg ts. the Usual ^Iethod 

 OF Spraying With a Power Machine. 



The dusting method is very miich quicker than the other method. It took 

 me an average of l^o hours to spray both sides of 92 very large apple trees. "With 

 a power outfit and liquid spray applying 960 gals, per day, it would have taken at 

 least 12 hours to do the work as thoroughly. This means that on such trees the 

 dust spray was eight times the more rapid. On smaller trees, such as plums or 

 cherries, which with a liquid outfit may l>c well sprayed as the horses move slowly 



3 K.S. 



