68 



CIRCULAR 270, U.S. DEPARTMENT OF AGRICULTURE 



LIME-SULPHUR 



Lime-sulphur solution has many uses in controlling certain insect 

 pests and fungous diseases of fruit trees. It may be used as a dormant 

 spray and also, in a more dilute form, as a summer spray. In the 

 latter case it is valuable chiefly as a fungicide. The strength of the 

 concentrate varies, and should be ascertained from the manufacturer 

 or by means of the Baume or specific-gravity scale on a lime-sulphur 

 hydrometer. The quantity of the concentrate required to make 100 

 gallons of diluted spray for various purposes is shown in table 1 . Dry 

 lime-sulphur is sometimes used in order to avoid the need of trans- 

 porting the heavier liquid material. It has not proved so effective 

 against the San Jose scale as the standard lime-sulphur concentrate. 



Table 1. — Dilution of concentrated lime-sulphur solutions for various strengths of 



spray 



Strength of concentrated lime-sulphur 



Quantity ' of concentrated lime-sulphur 

 required to make 100 gallons of spray 

 solution 



Degrees Baume' 



Specific 

 gravity 



Dormant 



strength 

 for scale 



(4H° 

 Baume) 



Dormant 

 strength 



for 

 blister 

 mite and 

 twig 

 borer 

 (3H° 

 Baume) 



Early 

 spring 

 strength 

 for scab 

 and red 

 spiders 



(1H° 

 Baume) 



Spring or 

 summer 

 strength 

 for mil- 

 dew and 



red 

 spiders 



(1° 

 Baume) 



36 



1.330 

 1.306 

 1.295 

 1.283 

 1.272 

 1.261 

 1.250 

 1.239 

 1.218 

 1.198 

 1.179 

 1.160 



Gallons 

 10 



10H 



11 

 liM 



ny 2 



12 

 12H 



13H 

 MM 

 1634 

 18% 



Gallons 

 7 



7A. 

 7% 



8 



SH 



sy 2 



9 



10 

 11 

 12H 



14 



Gallons 



3 

 3 

 3 

 3 



3H 

 3M 



VA 

 5 



Gallons 

 1% 



34 



m 



33_ . 



2 



32 



2 



31 



2 



30 



2 



29 



2% 



28. _. 



2% 



26 



2 X A 



24 



2% 



22--. 



3 



20- 



3K 







1 All quantities expressed in nearest quarter gallon. 



LUBRICATING-OIL EMULSIONS AND MISCIBLE OILS 



Lubricating-oil emulsions are extensively used in the Pacific North- 

 west for controlling the San Jose scale, red spiders, and leaf rollers, 

 and are also used against the codling moth and other insects. They 

 may be purchased as emulsions, or in the form of miscible oils that 

 emulsify when diluted with water. If the grower desires to prepare 

 his own emulsions, the following formula may be used : 



Water 33 gallons. 



Ammonia (28 percent) 1 quart. 



Casein (finely powdered) 3 pounds. 



Oil 100 gallons. 



Put the water into the spray tank, and, with the pump and agitator 

 running, add the ammonia and then sift in the casein slowly. As soon 

 as the latter has dissolved, which will be almost immediately, add the 

 oil about as fast as it will run from the drum. Be sure to let the 

 oil run in slowly until the agitator is well covered, or a reversed 

 emulsion may result. (A reversed emulsion will not mix with water 

 and cannot be used.) Allow the mixture to be stirred thoroughly by 

 the agitator for a few minutes and then pump it through a piece of 



