Ift FARMERS'" BULLETIN 933. 



hollows of the cones are broken and it is much easier to attain a per- 

 fect wetting of all the foliage. The object in spraying a citrus tree 

 should be the complete wetting of both the upper and lower surfaces 

 of the leaves in the shortest possible time. The writer has found 

 after many years' experience that much time is wasted in using noz- 

 zles of small capacity. It requires at least twice as long to spray a 

 tree using a nozzle with a very tiny hole in the disk as it does using 

 one of proper capacity. It is advisable to use a disk with tin opening 

 not less than one-twentieth of an inch in diameter and not greater 

 perhaps than one-sixteenth of an inch. 



SPRAYING ACCESSORIES. 



Every outfit, whether it be a barrel pump, a large lever pump, or a 

 power outfit, should be fitted with a wrench, pliers, hammer, and 

 such other tools as are necessary. It will also save much trouble and 

 annoyance if the materials which are placed in the tank are first 

 strained through double thicknesses of cheesecloth. This will cost 

 only a few cents and, according to the experience of the writer, may 

 save several dollars a day in time. In case a small leak appears in 

 the hose it can be dried carefully with a cloth and repaired with 

 adhesive or "tire" tape; this has been known to double the dura- 

 bility of a hose. Copper wire or other wire should be available in 

 order to repair hose connections in case they should separate. Patent 

 hose clamps are now to be had, and if used these will eliminate much 

 of the trouble usually arising from the separation of connections. 

 Each outfit should be provided with proper measures and buckets 

 to enable the operator accurately to calculate the amount of the 

 insecticide used, besides buckets for filling the tank. 



INSECTICIDES. 



The pests of citrus trees considered in this bulletin may be divided 

 into two groups with relation to the insecticides involved. (1) Those 

 controlled by the soap-and-oil sprays, such as the white flies and scale 

 insects; and (2) those controlled by the sulphur sprays, such as the 

 rust mites and red spiders. 



INSECTICIDES FOR WHITE FLIES AND SCALE INSECTS. 



Experiments covering a 10-year period have shown that the best 

 insecticides for controlling white flies and scale insects are those 

 having a base of cheap lubricating oil or what may be called " par- 

 affin oil." These oils are made into emulsions according to the for- 

 mulas following. 



Fish-oil soap at the rate of from 5 to 8 pounds to 50 gallons of 

 water in May, or from 12 to 16 pounds to 50 gallons of water during 

 the winter season, is an effective spray that has been used for many 

 years without injury to the foliage or fruit. 



