4 
BUREAU OF PLANT QUARANTINE 
IJan.-Mar. 
mixer, such as a concrete mixer. Plants must be free from soil when potted in 
soil treated in this manner. 
Period of treatment. — Plants freed from soil and potted in soil treated in the 
above manner by August 1, may be certified for shipment between the following 
October 1 and the subsequent June 15. 
Handling of treated soil. — When plants, potted in lead-arsenate-treated soil, 
are plunged in beds or set in frames exposed to possible infestation, the soil of 
these beds or frames must previously have been treated with lead arsenate at the 
rate of 1,500 pounds per acre. 
B. Sand, soil, earth, peat, compost, and manure shipments 
Regulation 7, quarantine no. 48, authorizes certification of sand, soil, earth, 
peat, compost, and manure, providing it has been treated under the supervision 
of and in manner and by method satisfactory to the inspector. If the carbon 
disulphide method is used, follow the detailed instructions given for the fumiga- 
tion of potting soil with carbon disulphide (1, A. 1). The only other method 
which may be used is steam, in which case the instructions for steam treatment 
should be followed (1, A. 3). 
Top soil or other materials from within 12 inches of the soil surface, to receive 
certification, must be treated throughout the year. 
Pit sand, from infested areas, must be treated during the period June 15 and 
October 15, inclusive, since infestation is likely to occur between the time of 
removal from the pits and loading in the cars. 
B. 1. Carload treatment requirements, June 15 to October 15, inclusive 
Type of car. — Tight box cars must be used during this period. Open cars may 
be used providing they are protected from reinfestation while within the regulated 
area. 
Doors. — The doorways of box cars must be boarded up and covered with heavy 
paper up to a point beyond the height of the sand or soil in the car. 
Depth of soil or sand. — The sand or soil must not be loaded in the car to such a 
depth as would restrict the overhead working space and hamper the work of the 
men performing the fumigation. 
Keeping doors closed. — Certified cars must have doors closed and fastened while 
en route within the regulated area. 
B. 2. Carload treatment requirements, October 16 to June 14, inclusive 
Type of car. — Open freight cars may be used during this period of the year, 
but they must be of steel gondola type. In cars with dump bottoms, planks must 
be laid across the bottoms and these covered with heavy paper to cover the 
openings. Where this is necessary, the inspector must give his approval before 
the sand or soil is loaded. 
Depth of soil or sand. — The soil or sand must not be piled above the level of the 
sides of the car. 
Covering with canvas. — When open cars are used canvases or heavy paper must 
be used for covering the surface as it is fumigated. These canvases or covers 
must be free from holes and a foot or more wider than the width of the car. 
Where several pieces of covers are used they must be large enough to allow for 
overlapping of at least a foot where they meet. The covers must be fastened 
down at the sides of the car and weighted on the surfaces, particularly where they 
overlap. 
C. Soil in and around plots, coldframes, hotbeds, etc. 
Soil in and surrounding plots, coldframes, hotbeds, etc., which is used for 
plunging pots or heeling-in plants, must be disinfected by treatment with lead 
arsenate as precribed in section C. 1. Under special conditions or specific 
authorization from the inspector, fumigation with carbon disulphide, carbon 
disulphide emulsion, or naphthalene may be substituted for the temporary 
elimination of infestation. 
C. 1. Treatment with lead arsenate 
Material. — Powdered acid lead arsenate. 
Condition of soil. — The soil must be friable and in good tilth. 
Season. — Treatment must be applied before August 1 if the land is to be used 
that autumn. 
