22 
recent bulletins and correspondence) it becomes at once evident that 
too little weight has been given to the possibility of the use of pure 
kerosene upon living plants — its insecticide qualities not having been 
doubted — and that the experiments of Professor Webster's correspond- 
ent in 1895-96 bid fair to lead us* to important results. It is true, as 
was pointed out in Bulletin Xo. 3, that Matthew Cooke as early as 1882 
reported the successful use of coal oil for the San Jose scale, although 
in the same year (Ann. Eept. U. S. Dept. Agric, 1881-82, p. 208) he 
shows that in oue orchard all peach trees were killed by its use and 
that many young apple orchards had been destroy ed. Also in his 
well-known book on " Injurious Insects of the Orchard, Vineyard," etc., 
he publishes the caution, under the head of "San Jose scale," " Beware 
of mineral oils." 
To Dr. Smith, however, must be given the credit of showing the best 
way to apply the oil — the only safe way, if there be a safe way. His 
latest publication (Bull. 125, X. J. Agr. Exp. Sta.) shows how guarded 
we must be in applying kerosene, and from one point of view it is a pity 
that his original circular of September, 1897, 'did not emphasize to a 
greater degree these safeguards, since it undoubtedly encouraged work 
by which hundreds of trees have been destroyed. As an instance, we 
may mention the case of a North Carolina correspondent, who, having 
seen the newspaper publications of the kerosene method in September, 
1S97, and having found the San Jose scale scattered more or less over an 
entire orchard of 100 acres of peach trees, sprayed with kerosene pretty 
thoroughly all portions of the infested trees. The result was that on 
January 10, 1898, he reported to this office that at least 90 per cent of 
the sprayed trees were dead. The correspondent was much discour- 
aged by this result and was inclined to think that the only remedy is 
to dig and burn the trees. It is from such experiences as this that we 
have decided not to recommend the pure-kerosene spray as the result 
of anyone's experience without first advising the individual fruit 
grower to experiment in a small way and determiue for himself by 
experience in his own locality and under the local conditions which 
exi*t there whether he can use kerosene to advantage. This warning 
will not be necessary, perhaps, in the case of men of reasonable caution, 
but it is evident that there will be many who will need it. Mr. J. H. 
Hale, as an example of the former class, informed the writer in conver- 
sation on February 9, 1898, that in spite of what had been written he 
intended to conduct careful experiments on a small scale, both at his 
Georgia and Connecticut places, wisely deeming that the details of a 
process which might be successful in portions of New Jersey might not 
be identical with the details in Georgia, and that here again, with con- 
ditions varying from those in Connecticut, identical results might not 
ensue in the latter State. In other words, if the writer were a fruit 
grower he would experiment for himself with the kerosene and upon 
his own individual results he would base his conclusions. 
