74 
and the latter in Orchard T. The whale-oil soap was used March 23 
and 24 in the ordinar}^ ratio of 2 pounds to the gallon of water on a 
plot immediately beside the check plot of its orchard. As the row 
adjacent to the check showed much the highest infestation of any 
one of the seven, it has been thrown out in the comparison. 
September 10 the infestation of this plot was reckoned at 1.9 de- 
grees, which, compared with that of the check plot at the same time,, 
gives a benefit ratio of 65 per cent. — making this solution virtually 
the equivalent of the California washes made with salt,' as shown in 
Table I. Its cost, $8 per hundred gallons of the solution — nearly 
eight times that of the California washes, — is the most serious ob- 
stacle to its general use. Except for its occasional destruction of 
blossom buds of the peach and other especially sensitive fruits, it 
would still remain the most desirable for use on a small scale. For 
the apple orchard, if the difference in expense is not worth consider- 
ing, it is to be recommended as among those next in efficiency to the 
simple lime and sulphur washes. 
"Tak-a-nap" soap dissolved in cold water at the rate of one 
pound to the gallon, and applied March 24 to 8 trees in Orchard I., 
gave an apparent September benefit of 15 per cent. The cost is $5 
for one hundred gallons. 
A caustic-soda solution made with water at the rate of i pound 
to 6 gallons and applied to 3 trees March 24 produced no percep- 
tible effect, these trees being, in fact, worse infested in September 
than they were in January, and even worse than were the trees of 
the check plot at the September inspection. 
Mention may also be made of Bowker's Tree Soap, used on only a 
single tree, but there apparently with very good effect. It was ap- 
plied i\Iarch 24 to a badly infested tree in Orchard I. at the rate of 
2 pounds of soap to a gallon of warm water. 
At the time of the May inspection 100 scales from this tree were 
counted, all of which were dead, and Mr. Taylor remarks that he 
could not find a scale on this tree alive, though he scraped and ex- 
amined most of the twigs to their tips. By September, however, 
this tree was moderately infested, possibly by invasion from adja- 
cent trees which had been treated with kerosene emulsion. 
This soap costs 7^^ cents per pound in 100-pound kegs, bringing 
the cost of the spray to $15 per hundred gallons. 
Cost of Materials 
The cost of all the materials contained in the various insecticides 
used in these experiments is shown in the last column of the tabular 
