1929] SERVICE AND REGULATORY ANNOUNCEMENTS 65 
temperature the more readily the vapor diffuses through the soil, and the more 
easily the immature stages of the beetle are killed by its action. The tempera- 
ture must be at least 45° F. when the treatment is applied. It must not fall 
below 40° F. during the course of the treatment ; otherwise, it will be necessary 
to treat the soil again to insure destruction of the immature stages of the 
beetle. 
Dosage. — Carbon disulphide must be used at the rate of 1 pound, or 350 cubic 
centimeters, to 1 cubic yard of soil. 
Application to soil. — Any quantity of soil may be fumigated, providing the 
carbon disulphide is distributed uniformly throughout. One method is to treat 
the soil while the box is being filled. Place 18 inches of soil loosely in the box; 
inject carbon disulphide at the rate of 170 cubic centimeters for each square 
yard of surface, distributing the material uniformly in holes 2 inches deep and 
18 inches apart, 44 cubic centimeters to each hole. Fill the holes with soil 
immediately after the Lquid is injected. When the first 18 inches of soil has 
been treated, put in 18 inches more, and treat it the same as the first. This 
can be repeated until the box is filled. Another method is to treat the soil 
after the box has been filled. This is done by making holes from the surface 
to the different levels, so that the carbon disulphide can be applied in the same 
positions as by the other method. The liquid, in this case, must be poured into 
the deep holes through a tube to insure its reaching the proper level. 
Period of fumigation. — The box must be sealed, and left undisturbed for 
at least 48 hours. 
Storage of soil. — The soil must be stored under such conditions as will prevent 
reinfestation. 
A. 2. Treatment of potting soil with naphthalene 
Material. — Flake naphthalene free from tar must be used for fumigation. 
Caution. Naphthalene will burn. It must be kept away from fire of all kinds. 
Equipment. — It is not necessary to have a special fumigation box in which 
to treat soil with naphthalene. 
Condition of soil. — Dry or moist soil of any type may be treated with naph- 
thalene. Wet soils can not be treated satisfactorily. 
Temperature. — The effectiveness of the treatment depends to a large extent 
upon the temperature of the soil ; the higher the temperature the more effective 
the treatment. The temperature must never be allowed to fall below 50° F. 
Dosage. — Five pounds of flake naphthalene must be used to a cubic yard of 
soil. 
Mixing. — The success of the treatment depends to a large extent upon tjie 
thoroughness with which tlii Hakes are mixed with the soil. Spread the flakes 
on the soil and mix thoroughly by shoveling over at least three times. 
Period of fumigation. — Soil must be left undisturbed for a week after 
.treatment. 
Storage of toil. — The soil must be stored under such conditions as will pre- 
vent reinfestation. 
A. 3. Treatment of potting soil with steam 
Equipment. — It is necessary to have a boiler (hat will generate an ample 
supply of steam under 70 DOUnd8 pressure; and equipment \'<>v properly dis- 
persing the steam throughout the --Mil. 
Condition of soil. — Soil of any type may be sterilized with steam, providing 
it is friable. 
Temperature.- The soil must be heated throughout to a temperature 
130° F. 
Period of treatment. — The soil temperature must ho maintained for 30 min- 
utes after it has reached 130° i\ throughout the mass. 
Storage of soU. After treatment with steam, soil must he stored and handled 
so .-is to prevent reinfestation. 
/;. Disinfection of Sand, Soil, Worth, Peat, Compost and Manure Shipments 
Th ly disinfection method authorised (Q. L8 reg. 7: Q. 06 reg. <">> as a basis 
for the certification ..r sand, soil, earth, peat, compost, and manure for ship- 
ment outside the regulated areas Is carbon disulphide fumigation, in employing 
S0297— 30 3 
