DUST SPRAYING 



IN the Western States, particularly in the 

 State of Missouri, where orchards are 

 often on steep hillsides, and where water is 

 sometimes scarce, fruit growers have been 

 looking about for some easier way of apply- 

 ing fungicides and insecticides than by 

 means of water, which is difficult to get and 

 more difficult to draw over the rough 

 ground. Trees have been dusted with sul- 

 phur and other materials in the east in the 

 past, but copper sulphate had not been used 

 in this way until tried in the west. Ma- 

 chines for spraying dust mixtures have been 

 invented or old ones improved upon, and 

 during the past few years dust spraying has 

 been carried on in a number of commercial 

 orchards in the Western States and quite 

 satisfactory results are said to have been ob- 

 tained. 



Air-slaked lime has been used in the place 

 of water for carrying the fungicides and in- 

 secticides, but it in itself has a beneficial ef- 

 fect also. The formula recommended up 

 to .the present year were not entirely satis- 

 factory, as they did not contain the copper 

 in the same chemical condition as in Bor- 

 deaux mixture. Experiments were con- 

 commended which is said to have the cop- 

 per in the right chemical condition. The 

 formula, with the method of preparation, is 

 given in Bulletin No. 60, Missouri Experi- 

 ment Station, Columbia, Mo. 



A dust machine was obtained from the 



Ozark Dust Sprayer Co., Springfield, Mo., 

 and tested at the Central Experimental 

 Farm, Ottawa, in 1903, by the writer. It 

 was found to distribute the dust satisfac- 

 torily, but in order to get the dust to adhere 

 it must be applied when the dew is on the 

 foliage. This is a serious drawback to dust 

 spraying in this time of scarcity of labor. 

 Moreover, the liquid spray gives such satis- 

 factory results when properly made and ap- 

 plied that the dust spray is not likely to take 

 its place, except perhaps where the ground 

 is rough and where the orchards are on 

 steep hillsides, and possibly in spraying 

 young trees. It would appear at first that 

 there was great danger from the use of 

 arsenical poisons when applied in a dust 

 spray, but while there is undoubtedly danger 

 if the dust is inhaled, the nozzle is so far 

 away from the operator that there is really 

 little danger if the work is carefully done.' 



As there was no apple spot fungus this 

 year, and practically no codling moth, ac- 

 curate comparison could not be made be- 

 tween the efl^ectiveness of the dust and li- 

 quid sprays, but the general conclusions 

 reached by experimenters elsewhere are that 

 although good results may sometimes be ob- 

 tained by dust spraying, it is not the best 

 method for general use. 



W. T. Macoun, 

 Horticulturist Central Expl. Farm, Ottawa. 



HEIGHT OF FRUIT TREES 



THERE is considerable difference of 

 opinion among orchardists as to the 

 height at which fruit trees should be headed. 

 In the Eastern States there are many who 

 think the trunks should be four or five feet, 

 and some of the apple orchards have bodies 

 taller than this. However well this may he 



for the eastern conditions, it is not the pro- 

 per way to train trees anywhere in the Cen- 

 tral and Western States, and in the east the 

 tendency is to lower heads. The more re- 

 cently planted apple orchards are rarely over 

 two to three feet to the lower branches, and 

 the pear orchards from one to two feet. 



