GAS TREATMENT FOR TOBACCO 7 
surface. After the bed is prepared (fig. 2, A), the tobacco cloth is 
drawn over and the muslin cover stretched along one side and fastened 
by two of the corner stakes; then the paradichlorbenzene is scattered 
(fig. 2, B), and the muslin i is drawn over, by taking hold of the ends 
of the wire running through the free side. After the muslin has been 
tightly stretched, the other two corner stakes are driven in, the clamp 
stakes are pushed i in, and, as this is done, any loose muslin is pulled 
between wire and soil surface where the clamp stakes hold it firmly. 
The muslin is held down at the two ends by a few poles (fig. 2, C). 
With the muslin fitting close to the ground and drawn tightly over 
the log tops, gas retention is excellent. It is es sential, however, that 
the muslin be considerably larger than the plant bed. 
The wired muslin cover and stakes can easily be carried from one 
bed to another, and a cover 8 yards wide can readily be used on a 
6-yard-wide bed by merely drawing the extra cloth under the wire 
before clamping this to the ground. Two men are required to handle 
muslin covers of this type. 
A second and very satisfactory method for treating log beds is 
shown in the cover illustration. After the side-wall logs have been 
lined up and the cracks filled, as described for the first method, the 
bed is divided by a center partition into halves. In the bed illus- 
trated, the sections were 4 yards by 20 yards, and the pole supports 
were placed 2 yards apart, with a wire 15 inches above the ground 
running lengthwise of each of the sections. The tobacco cloth 
(shown at the left of the illustration) was stretched over the section 
to be treated and the paradichlorbenzene scattered on it. The 
muslin, which was fastened along the center partition, was then 
drawn across. The free edge of this cover had a fold with a wire 
running through it, and iron stakes were used at either end, with 
clamp stakes between, just as in the previous arrangement. Thus 
the same muslin was used for each half of the bed on alternate nights. 
Between treatments the muslin was left conveniently rolled up in 
the center. 
Many modifications can be made in the plans suggested, and other 
entirely different plans can be used successfully. However, the 
flexible wire to hold the free side of the muslin has been of great 
advantage in the case of log beds and, similarly, iron stakes have 
proved superior to wooden because they are so much easier to drive 
in and pull out of the ground. 
Experience Should Be Gained on Small Bed Areas 
How much bed area should a grower attempt to treat who is using 
paradichlorbenzene for the first time? 
If the paradichlorbenzene is effective and can be used with both 
narrow and wide beds, it would appear logical to recommend that 
growers treat all their beds, which might be anywhere from 100 to 
1,000 square yards ormore. However, this seems inadvisable for two 
reasons: (1) It is simple to prepare 100 square yards of plant bed for 
gas treatment, but as the labor and expense increase almost propor- 
tionally with the area, the situation is very different from that which 
obtains with the spray treatment, where, after the preliminary prepa- 
rations are made, it is almost as easy to spraya large bed area as it isa 
small one. (2) If the paradichlorbenzene treatment is improperly 
earried out, serious plant injury may result. Therefore, it is advisable 
that the grower obtain some experience on a relatively small area, 
