
41 
more than compensates for the cost of the treatment. The value of 
these fertilizers against the wireworms is, however, questioned by 
Prof. J. H. Comstock. 
For the root-aphis of peach and apple, work the fertilizer into the 
general surface of the soil about the trees, or put it into a trench 
about the tree 2 feet distant from the trunk. 
For cabbage and onion maggots, apply in little trenches along the 
rows at the rate of 300 to 500 pounds to the acre, and cover with soil. 
These fertilizers (and the nitrate of soda is nearly as good) are also 
destructive to the various insects which enter the soil for hibernation 
or to undergo transformation. 
BISULPHID OF CARBON. 
This is the great French remedy for the phylloxera, 150,000 acres 
being now subjected to treatment with it, and applies equally well to 
all other root-inhabiting aphides. The treatment is made at any 
season except the period of ripening of the fruit and consists in mak- 
ing holes about the vines 1 foot to 16 inches deep and pouring into 
each about one-half ounce of the bisulphid, and closing the holes with 
the foot. The injections are made about 13 feet apart, and not closer 
to the vines than 1 foot. It is better to use a large number of small 
doses than a few large ones. Hand injectors and injecting plows are 
employed in France to put the bisulphid into the soil about the vines, 
but a short stick or iron bar may take the place of these injectors 
for limited tracts. 
The use of bisulphid of carbon for the woolly aphis is the same as 
for the grape root-aphis or phylloxera. It should be applied in two 
or three holes about the tree to a depth of from 6 to 12 inches and not 
closer than 14 feet to the tree. An ounce of the chemical should be 
introduced into each hole, which should be immediately closed. 
For root-maggots a teaspoonful is poured into a hole near the base 
of the plant, being covered as above. 
For ant nests an ounce of the substance is poured into each of sev- 
eral holes made in the space occupied by the ants, the openings being 
then closed; or the action is made more rapid by covering with a 
wet blanket for ten minutes and then exploding the vapor at the 
mouth of the holes with a torch, the explosion driving the fumes 
more thoroughly through the soil. 
SUBMERSION. 
This very successful means against the phylloxera is now practiced 
over some 75,000 acres of vineyards in France which were once de- 
stroyed by the grape root-aphis, and the production and quality of 
fruit has been fully restored. In this country it will be particularly 
available in California and in all arid districts where irrigation is 
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