28 BUREAU OF ENTOMOLOGY AND PLANT QUARANTINE [Jan.-March 
§301.72-5, Chapter III, Title 7, Code of Federal Regulations (Regulation 5 of 
Notice of Quarantine No. 72 on account of the white-fringed beetle) any one of the 
following methods of treatment for potting soil is hereby authorized when car- 
ried out under the supervision of an authorized inspector of the United States 
Department of Agriculture. 
(b) Carbon disulphide fumigation. — (1) Potting soil shall be treated in a con- 
tainer with carbon disulphide at a dosage of 2 pounds per cubic yard of soil for a 
period of 48 hours. 
(2) The grade of carbon disulphide shall be comparable to U. S. P. grade having 
a specific gravity of 1.25 at 68° F. 
(3) The container shall be tight, preferably lined with sheet metal, and shall 
have a tight cover or be covered with a tarpaulin immediately after the fumigant 
is applied. The container shall not be more than 36 inches deep. 
(4) The soil shall be friable, and wet soil shall not be treated by this method. 
The fumigant shall be applied to the soil in holes 3 inches deep, the dosage to be 
evenly divided among holes 1 foot apart over the surface of the soil, and the 
fumigant shall be covered with soil as soon as it is applied. 
(5) The temperature of the soil shall not be lower than 40° F. during the 
entire time of treatment. 
(6) The condition of the soil and the apparatus used and the method of applica- 
tion of the fumigant must meet with the approval of an authorized inspector 
of the United States Department of Agriculture. 
(c) Methyl bromide fumigation. — (1) Potting soil must be treated in a con- 
tainer with methyl bromide in a dosage of 40 cubic centimeters of methyl bro- 
mide per cubic yard of soil for a period of 48 hours. 
(2) The sides, bottom, and seams of the container shall be tight, preferably lined 
with sheet metal, and shall have a cover or be covered with a tarpaulin imme- 
diately after the fumigant is applied. 
(3) The condition of the soil and the apparatus used and the method of appli- 
cation of the fumigant must meet the approval of an authorized inspector of the 
United States Department of Agriculture. 
(d) Heat treatment. — (1) Live steam, under pressure of 80 pounds or more 
per square inch, shall be applied through a grid of perforated pipes at the bot- 
ton of the sterilizing box or truck body containing the soil, for a period of 45 
minutes or until all parts of the load reach a temperature of 200° F. 
(2) The grids shall be constructed of 1-inch pipes, perforated with holes %2 
inch in diameter on the upper side and connecting at one end to a manifold into 
which the steam is introduced. 
(3) The layer of soil in the sterilizing box shall not be more than 2 feet, 6 
inches deep. 
(e) Disclaimer. — In authorizing the movement of potting soil treated according 
to the requirements stated above, it is understood that no liability shall attach 
either to the United States Department of Agriculture or to any of its employees 
in the event of injury resulting from the use of these treatments. 
(f) Caution. — (1) The vapor of carbon disulphide is inflammable and ex- 
plosive. At a temperature of 297° F. it may take fire spontaneously and in the 
presence of certain metals, particularly copper, it may ignite at considerably lower 
temperatures. It must be kept away from fire, and from hot objects such as 
electric light bulbs, unprotected brush-type motors, steam pipes, etc. Lighted 
cigars, cigarettes, or pipes must never be brought near carbon disulphide. 
Carbon disulphide is a blood poison, but poisoning by this chemical is rare. 
Exposure to the vapor may cause giddiness and headache. When these symptoms 
develop, the individual should get into the open air. 
(2) Methyl bromide is a gas at ordinary temperatures. It is colorless and 
practically odorless in concentrations used for fumigation of plants. It is a 
poison, and the operator should use an approved gas mask when exposed to the 
gas at concentrations used in fumigation. After fumigation of potting soil by 
that method, the cover should be removed and the soil allowed to become aerated. 
A VERY S. HOYT, 
Acting Chief. 
[Filed with the Division of the Federal Register March 21, 1941, 11 : 37 a. m. ; 
6 F. R„ 1571.] 
