Reports to the Board of Agriculture . 33 
must be put in the earth between the plants. Care must be taken, 
as it is of an inflammable nature and the fumes are also poisonous. 
(ii) Trapping largely employed for wire-worm consists of placing- 
pieces of carrot, mangel, beetroot or turnips in the ground, and taking 
them up every few days and collecting the wire-worm that are 
feeding upon the “bait.” Millepedes may also be caught in this 
way, but for them large hollow, more or less rotten, roots form the 
best trap. It has also been found that the small millepedes ( Julus 
pulchellus) may be caught in numbers by placing cabbage leaves 
soaked in a solution (1 oz. to the gallon of water) of Paris green 
on the ground. The millepedes come to the surface at night and 
feed upon the leaf and are so poisoned. 
Bisulphide of carbon treatment is best ; failing that, some good 
may be done by trapping by means of ground bait. 
Directions for the Employment of the Gas 
Treatment under Glass. 
Several enquiries have been received concerning the destruction 
of greenhouse pests. 
Various methods of fumigating plants under glass are employed, 
such as sulphur fumes and tobacco smoke. Neither of these are as 
good as the employment of hydrocyanic acid gas. For Aphides, 
Red Spider, and Wood Lice the following quantities are necessary : 
2 ozs. of cyanide, 4 ozs. sulphuric acid, 7 ozs. of water per 1000 
cubic feet of space. Proceed as follows : Pour the water into a jar, 
then add the acid to the water. Wrap up the cyanide in a piece of 
blotting-paper and drop it into the jar of acid and water from outside 
the house. This can be done by tying the cyanide bag on to a stick 
with a longisli piece of string, then close the door or window. Leave 
the house shut up for at least three-quarters of an hour, then open all 
doors and windows to ventilate freely ; be careful not to enter the 
house for at least an hour after the doors and windows have been 
thrown open. Fumigate at dusk and when the foliage is dry. The 
temperature must not be above 60° F. The best temperature is 
50° F. ; above 60° F. the foliage gets scorched, as it also does if you 
fumigate in bright light. If the house is more than 10,000 cubic 
feet two jars would be necessary, but up to that size one is ample. 
The result of one experiment may be quoted here. Greenhouse, 
2,000 cubic feet, containing Chrysanthemums in full bloom, severely 
infested with Green Fly. Cyanide 3^ ozs., acid 5 ozs., water 9 ozs. 
Temperature 50° F. Time 25 minutes. 1 hour after sunset. 
D 
