1942] 
SERVICE AND REGULATORY ANNOUNCEMENTS 
53 
Treatment of Soil About the Roots of Plants 
(1) treatment of plants after diguing 
* * .* * * * 
(6) Ethylene dichloride emulsion dip 
(i) Materials: 
Potassium hydroxide: C. P. 
Alcohol: 190 proof ethyl alcohol. 
Oleic acid: crystal white olein. 
Ethylene dichloride: commercial. 
(ii) Formula: 
Potassium hydroxide 1 
Alcohol 2 
Water 
Oleic acid 
Ethylene dichloride 
100.0 
1 An amount of commercial caustic potash containing an equivalent weight of potassium 
hvdroxide mav be substituted for the C. P. grade. 
* 2 Completely denatured alcohol (190 proof) may be substituted for the ethyl aleono; 
(190 proof). 
(iii) Preparation of dip. — Mix the several ingredients in the order given in 
the formula. Dissolve the potassium hydroxide in the alcohol and water, add 
the oleic acid, and stir intermittently for about 10 minutes. Compensate for 
evaporation loss by the addition of alcohol and water in the ratio given in the 
formula. Add the ethylene dichloride and stir. 
The emulsible ethylene dichloride shall have a specific gravity of about 1.070 
at 25° C. (77° F.) and contain 60 percent by weight of ethylene dichloride. 
It shall be a clear solution that may be readily diluted with water to form a 
uniform, stable, milklike emulsion. The product should be kept in gastight 
containers in a cool place at a temperature above 4.5° C. (40° F.). At lower 
temperatures it will separate into layers, in which case it must be warmed to 
room temperature and stirred to restore it to its original and usable condition. 
(iv) Caution. — Ethylene dichloride is an inflammable volatile solvent. It. 
the emulsible ethylene dichloride, and the ethylene dichloride emulsion should 
be kept away from fire, heat, and open flame. They should be used with ade- 
quate ventilation and prolonged breathing of the vapor should be avoided. 
(v) Season. — The treatment must be applied between October 1 and June 1. 
(vi) Temperature. — The temperature of both the dip and the plant balls at 
the time of dipping shall not be lower than 45° F. nor higher than 75° F. At 
no time thereafter, during the holding period, shall the temperature of the 
treated plant balls be lower than 40° nor higher than 80°. 
(vii) Dosage. — Use at the rate of 1 gallon of the emulsible ethylene di- 
chloride in 100 gallons of water. (For convenience in making small quantities 
use 40 cubic centimeters in 1 gallon of water.) To prepare the emulsible 
ethylene dichloride as a dip, add small quantities of water successively, stirring 
continually until a uniform, creamlike emulsion is formed. Dilute this emulsion 
with the remainder of the water, stir a few minutes to insure a uniform sus- 
pension, and pour into a trough or tank. This dip must be prepared immp- 
diateiy before using. 
(viii) Preparation of plants. — Plants with root masses or balls up to 10 inches 
in diameter at the narrowest dimension may be treated, either bare, wrapped, 
or in unglazed clay pots. If wrapped, the wrapping material must be of such 
a nature as not to prevent the proper penetration of the emulsion into the root 
mass. The plant balls shall be moist but not wet. 
(ix) Application. — The size of the trough or tank (wood or metal) used for 
the dipping vat, and the quantity of the emulsion shall be sufficient to provide 
a complete coverage of all the plant balls. The plant balls or pots must be 
immersed for a period of 10 seconds in the dip. They may be treated either 
Pounds 
2.5 
14.0 
6.0 
17. 5 
60.0 
