260 I^^'I^'"-^^^' <>t' ENTOMOLOGY AM) I'LANT QCAKAXTINK IOct.-Dec. 
Copies of these circulars have been sent to all collectors of customs for their 
information and guidance. 
The number of this Treasury decision should he inserted as a marginal 
refei-ence opposite articles 578 (&) (1), 579 and 580 («) of the Customs Kegu- 
latioiis of 1937. 
Jamks H. Moyle, 
Conimissioner of Customs. 
ANNOUNCEMENTS RELATING TO JAPANESE BEETLE QUARANTINE 
(NO. 48) 
B. P. Q. 359, Supplement No. 2. 
INSTRUCTIONS TO INSPECTORS ON THE TREATMENT OF NURSERY PRODUCTS, 
FRUITS, VEGETABLES, AND SOIL, FOR THE JAPANESE BEETLE 
OCTOBEE 15, 1937. 
Section II of Circular B. P. Q.-359 entitled, -Instructions to Inspectors on the 
Treatment of Nursery I'roducts, Fruits, Vegetables, and Soil, for the Japanese 
Beetle," is further supplemented as follows : 
II. Treu\tmext of Soil About the Roois of I'laxts 
F. P.U{ADICHLOROBENZENE TKEL\TMENT 
Tiie following instructions, based on the horizontal diffusion of gaseous para- 
dichlorobenzene, do not supplant the instructions given in supplement No. 1 to 
B. P. Q.-^59, issued August 23, 1935, but modify them in such a manner that the 
treatment can be applied more safely to the smaller sizes of nursery plants. 
Material. — Paradichlorobeuzene. A technical grade or C. I*, grade, ground 
into small-sized crystals, is satisfactory for this treatment. 
Condition of plunging soil. — I'aradichlorobenzene should be mixed with a light 
soil, which should be moist, friable, and relatively low in organic matter. It 
should be sifted through a half-inch mesh screen to remove large lumps, stones, 
and debris prior to mixing with paradichlorobeuzene. 
Condition, of plant hall. — The plant balls should be moist, hut not wet, and not 
over 6 inches in diameter. If the soil is wet the treatment will not be satis- 
factory ; if the soil is dry the plants may be injured during the treatment. 
Season. — Treatment can be made at any time between October 1 and May 1, 
providing the proper temperature conditions can be obtained. 
Temperature, dosage, and exposure requirements. — The various combinations 
of temperature, dosage and exposure which are effective in destroying the larvae 
in plant balls of different diameters are given in table 5. The temperatures 
^iven at the head of the different colinnns in table 5 are consideretl to be the 
minimum temperature during the treatment. 
Applieation of the treatment. — The treating-soil should be mixed immediately 
before being used, as follows : Spread the soil in a thin layer on a smooth sur- 
face of a tloor, bench, or other suitable space, scatter the crystals uniformly 
over the surface of the soil, and mix thoroughly by means of a shovel, rake, hoe, 
or fork, turning the mass at least three times during the operation. It is ne<-es- 
sary to remove the pots from potted plants before placing them in the treated 
.^oil. When the burlap on balled plants is of a coarse weave which will not 
inhibit the proper penetration of the gas, it may be left on the balls, but when 
the material is closely woven it should be removed. When the plants are i"eady 
tor treatment, a layer of the treated soil is spread on a smooth hard surface such 
MS a floor or bench. Then, a row of plants is placed on this soil with the balls 
spaced at least 1 inch apart. Then the spaces l>etween the plant balls are filled 
with treated soil, taking care not to get it on top of the balls or in contact with 
the stems. Finally, about 1 inch of treated soil is placed flrmly against the row 
of treated plants. The operation is repeated until all of the plants are in place. 
When completed, each plant ball is surroundtMl on the sides and bottom by at 
least 1 inch of treated soil. 
Care of plants (hiring treatment. — The plants should not be removed from the 
treated soil during the period of the treatment. If it is necessary to apply water 
to the plants during the treatment to prevent desiccation, the operation should be 
limited to a light syringing, under the supervision of an inspector. If sufficient 
water is applied to make the treated soil or the plant balls muddy, the insecti- 
cidal action of the gas may be seriously impaired. 
