Aphids Injurious to Orchard Fruits, Etc. 43 
contain, in addition to the water, about 10 per cent of caustic soda, 
58 per cent of fatty matter as anhydrides, and about 2 per cent of 
other matter. Soda fish-oil soap is generally of medium to hard con- 
sistency, whereas the potash soaps are much softer. They are 
brownish in color, with a distinct fishy odor. 
For foliage sprays the fish-oil soap is dissolved at the rate of 1 
pound in 3 to 4 gallons of water or at greater dilutions, depending 
upon the insects to be treated and the hardiness of the foliage. 
Soda soaps are fairly hard and usually require slicing and dissolving 
in hot water. 
Fish-oil soaps may be used with the following spray materials to 
increase their spreading and adhesive qualities: Arsenate of lead, 
nicotine solutions, Bordeaux mixture, and sulphur. Do not use soap 
wn lime-sulphur solutions, or in waters containing compounds of lime 
and magnesium (hard waters). 
HomEMADE FisH-o1t SOAP. 
A good fish-oil soap ' may be made at ordinary summer tempera- 
tures without the aid of external heat according to the formula given 
below: 
ButreteriOa ses. <a F.ctteek Nites. ct Sat en Seat ae le pounds.. 6 
Bebe meee atire FA Mose or ne fo Saris ary) > « pyhu o ee aes RR eee SS gallon... 4 
PReMIGUU omer eee ae eet S20 is, Ae Re 2 ee gallons.. 34 
Thoroughly dissolve the caustic soda in the required amount of 
water. Then, while stirring constantly, add the fish oil very slowly 
and continue active stirring for about 20 minutes or until the soap 
is complete. The homemade fish-oil soaps may be used in about 
the same proportions as the commercial products. 
Liquip FtsH-o1t Soap. 
Commercial liquid fish-oil soap may be substituted for the harder 
fish-oil soaps. Apply according to the directions given for fish-oil 
soap, using 1 pint of the liquid soap in place of 1 pound of the hard 
soap. Liquid soaps are especially convenient in making oil emulsions. 
Topsacco FisH-or Soar. 
Commercial fish-oil soaps containing a small percentage of nicotine 
are sold for insecticidal purposes. Soaps of this kind are somewhat 
expensive and their use is scarcely justified unless the nicotine is 
present in sufficient quantity to have distinct. insecticidal value, 
namely, 0.05 to 0.06 per cent in the completed spray. 
1 Van Slyke, L. L., and Urner, F.A. N.Y. Agr. Exp. Sta. (Geneva) Bul. 257. 1904. 
