GREENHOUSE AND COLD FRAME FUMIGATION 133 
A plain wooden box, such as is shown in Figs. 49 
and 50, or even a small Emory fumigator, as seen in 
Figs. 33 or 36, will be found very useful to florists 
and gardeners in any greenhouse or nursery grounds. 
This box can be used for the fumigation of small 
shrubs and plants on lawns, in gardens, and various 
other places where it is desirable to fumigate them 
without taking them up. The box may be used in 
the daytime if the work is done in a cool place. 
‘Some florists and nurserymen use small boxes in their 
packing-houses and cellars where the temperature is 
constant. Care must be taken, however, where the 
gas is generated and released in such places, to see 
that proper ventilation is secured to carry away the 
poisonous fumes when released from the box. Nurs- 
erymen handling ornamental plants can use their 
fumigating houses for the treatment of various shrubs. 
Some florists have found that a small greenhouse con- 
taining 1,000 feet or less is more reliable than a box. 
There is less danger of injury to the foliage under 
such conditions. 
Experience with various plants.—Although a large 
number of greenhouse plants have been fumigated, 
there is yet room for much careful experimental work. 
The following list of plants, given by Dr. Woods, 
have been fumigated. 
Ferns.—For Davallia mooreana, infested with a 
scale insect (Chionaspis sp.), 0.075 gramme of 98 per 
cent. potassium cyanide should be used for each cubic 
foot of space to be fumigated, not deducting the space 
occupied by the plants. Length of exposure, twenty 
minutes. 
