INSECTICIDES AND EQUIPMENT FOR CONTROLLING INSECTS 195 
it has supplanted unslaked lime or quicklime, in the preparation of 
bordeaux mixture. It is commonly used by growers as a repellent to 
insects on melons, cucumbers, and other vegetables, and to repel the 
Japanese beetle on certain fruit crops, although, owing to its caustic 
nature, it may retard development of some plants. It is recommended 
for the control of slugs and snails. 
For the preparation of bordeaux mixture the hydrated lime should 
be freshly made. 
Hydrated lime is commonly used with zinc sulfate on peaches and 
with either zinc sulfate or copper sulfate on apples, as a safener for 
lead arsenate. 
Caution.—The dust, when inhaled, is somewhat irritating to the 
respiratory passages. Keep containers well closed. 
This material is usually available locally, in | hardware stores or 
from dealers in building supplies. 
KEROSENE EMULSION 
Kerosene emulsion is an effective contact insecticide. It was in 
rather general use until replaced by the white-oil emulsions, which 
are safer to use on a wide variety of plants. If not properly prepared, 
kerosene emulsion may cause injury to succulent plants such as coleus, 
ferns, heliotrope, begonia, and crucifers, although it can be safely used 
on chrysanthemums, crotons, palms, and rubber plants. 
Other, hardier plants are not injured, even by a 10-percent emulsion. 
A 5- “percent emulsion is effective against mealybugs, rose midge larvae 
in the soil, immature scales, and red spiders, while a 1-percent emul- 
sion can be used successfully against aphids, thrips, and ants in the 
soil. Kerosene emulsion should be applied preferably late in the after- 
noon and the plants thoroughly syringed with water the next morn- 
ing before sun-up. Soil overrun with ants may be freed of these pests 
without injury to the plants by drenching the infested areas with a 
1-percent enrulsion. 
A stock emulsion of kerosene is prepared according to the following 
formula: 
For large For small 
quantities quantities 
ERE OSCTIG wins eens he I Ne eee 2 gallons. 1 pint. 
Fish-oil soap or laundry soap ____-______ 14 pound. 1% ounce. 
VViatie Tess Use es 7 2 toge ap Be et galion: 1% pint. 
If hard bar soap is used, first cut the soap into chips and then 
dissolve it in hot water, and while it is still hot add the kerosene very 
slowly, stirring constantly. The mixture should be pumped through 
a bucket pump back into the container for several minutes, or until 
a creamy emulsion has formed. Small quantities may be made with an 
ego beater. 
The stock emulsion may be kept until needed in a tightly stoppered 
bottle or fruit jar. However, it will deteriorate with age and the 
kerosene will collect at the top of the mixture. This is the case with 
some of the commercial emulsions which have been prepared for some 
time. This free oil is the cause of much injury when applied to plants. 
The emulsion may be reclaimed by reheating and agitating, with or 
without the addition of soap. 
