216 STATE BOARD OF AGRICULTURE. 



strengrth after a time, and may sometimes be used when paris-green 

 would not do. 



Now a word about applying the spray. In general use a nozzle that 

 will produce a fine spray, one that will stick in minute particles to the 

 plant and which will not go on in drops. Always stop spraying before 

 the plant commences to drip. Paris green, and all the arsenites, remain 

 in suspension in the water if properly prepared, and are not dissolved. 

 These small particles of poison will settle to the lowest part of a drop 

 of water, and remain on the plant as the water evaporates, if the drop 

 be of small size. If, on the other hand, the drops are large enough or 

 numerous enough to run together and drip off, most of the poison drips 

 oflf first, leaving very little to dry down on the plant. It is therefore 

 desirable to have the water evaporate as quickly as possible. This is 

 best brought about in dry, sunshiny weather. Such weather is best for 

 kerosene-emulsion also, because the oil is apt to injure the foliage if 

 left on too long before evaporating. Therefore choose dry, sunshiny 

 weather for spraying if possible. 



CONTACT INSECTICIDES, FOR INSECTS THAT SUCK. 



KEROSiSNE-EMULSION. 



Place two gallons of ordinary kerosene in a warm place, either in a 

 warm room or in the sun, and allow it to become as warm as possible 

 without danger from fire. Boil one pound of laundry or whale-oil soap 

 in a gallon of soft water until completely dissolved. Remove the soap 

 solution from the fire, and while still boiling hot, add the kerosene and 

 agitate for ten minutes, or until the oil is emulsified, with a spraying 

 pump by forcing the liquid back into the vessel from which it was 

 pumped. When the liquid is perfectly emulsified it will appear creamy 

 in color and will flow evenly down the side of the vessel when allowed 

 to do so. Care should be taken to completely emulsify the oil and this 

 is accomplished much more easily when the mixture is hot. This strong 

 emulsion may now be readily diluted with water and used, or it may 

 be stored away for future use. \Yhen cold it becomes like sour milk in 

 appearance and should be dissolved in three or four times its bulk of 

 hot water before diluting wilh cold water. If the water is at all hard, 

 "break'' it by adding a little salsoda before putting in the soap. 



Small amounts of this emulsion may be made by using the ingredients 

 in small quantities but in the same relative proportion. 



WHALE-OIL SOAP KEROSENE-EMULSION. 



This is made with whale-oil soap in place of the common laundry 

 soap. It is superior to the plain emulsion in some ways. 



PYRETIIRO WHALE-OIL SOAP KEROSENE-EMULSION. 



To one gallon of the undiluted emulsion made with whale-oil soap, 

 add one ounce of Pyrethrum. Stir well and dilute before applying. 



