294 INSECTICIDAL MATERIALS AND PRACTICES 



Distillate emulsion. 5 gallons of 28 gravity untreated distillate ; 

 5 gallons boiling water, ll pounds whale-oil soap. Dissolve the 

 soap in hot water, add the distillate, and thoroughly emulsify by 

 means of a power pump until a yellowish, creamy emulsion is 

 produced. For use on lemon dilute with 12 parts of water; 

 on orange, with 15 parts. 



Formerly much used on citrus trees, but now generally replaced 

 by fumigation. 



Hellebore. See WHITE HELLEBORE, p. 300. 



Hot water. Submerge affected plants or branches in water at a 

 temperature of about 125. For aphis. It will also kill rose-bugs 

 at a temperature of 125-135. 



Kerosene emulsion. Hard, soft, or whale-oil soap, i pound ; water, 

 1 gallon; kerosene, 2 gallons. Dissolve the soap in hot water ; 

 remove from the fire and while still hot add the kerosene. Pump 

 the liquid back into itself for five or ten minutes, or until it 

 becomes a creamy mass. If properly made, the oil will not sep- 

 arate out on cooling. 



For use on dormant trees, dilute with from 5 to 7 parts of water. 

 For killing plant-lice on foliage dilute with from 10 to 15 parts of 

 water. Crude oil emulsion is made in the same way by substitut- 

 ing crude oil in place of kerosene. The strength of oil emulsions is 

 frequently indicated by the percentage of oil in the diluted liquid: 

 For a 10 per cent emulsion add 17 gallons of water to 3 gallons 

 stock emulsion. 



For a 15 per cent emulsion add 10j gallons of water to 3 gallons 

 stock emulsion. 



For a 20 per cent emulsion add 7 gallons of water to 3 gallons 

 stock emulsion. 



For a 25 per cent emulsion add 5 gallons of water to 3 gallons 

 stock emulsion. 



Lead, arsenate of. See under ARSENICALS, p. 291. 



Lime-sulfur. A compound of lime and sulfur makes both a good insec- 

 ticide and a good fungicide (for an account from the fungicide point 

 of view, see page 256). There are several forms of it, as (1) the 

 ordinary dilute home-made ; (2) the concentrated home-made ; 

 (3) the commercial concentrated brands ; (4) the so-called self- 

 boiled preparation. The three first are solutions, and are modi- 



