New YorK AGRICULTURAL EXPERIMENT STATION. 249 
plum trees and in February to other varieties of fruit trees are 
considered as showing that undiluted petroleum does not injure 
fruit trees, although it may remain upon them for six months; 
also that it kills the scales when coming in contact with them 
and that it has given the most promising results of any of the 
insecticides that had come into use at that time. 
The experiments in this State by the State Entomologist, Dr. 
E. P. Felt, furnished one of the first published records of results 
with the insecticide in the north.2 A number of fruit and orna- 
mental trees were included in these experiments. The former 
consisted principally of wild cherry, peach, plum, pear, quince 
and crab apple. Twenty and twenty-five per ct. emulsions of 
crude petroleum and water were used as well as undiluted petro- 
leum. A1Il of the trees were sprayed in April. From these ex- 
periments Dr. Felt concludes that “the trees appeared to be 
uninjured by the insecticide* though possibly a little retarded, 
while a large proportion of the scales are killed and on some 
trees it would appear as though every one had been annihi- 
lated; ” also that the results with the 25 per ct. emulsion were 
not enough better to warrant the use of the higher percentage 
of oil and that owing to the serious injury to the trees treated 
with the undiluted petroleum its use cannot be recommended. 
THD PRESENT STATUS OF CRUDE PETROLEUM AS AN INSECTICIDE. 
The above review, which includes the principal experiments 
with crude petroleum yet published, brings out some points in 
which the results as reported do not agree. It will be noticed 
that Dr. Smith concludes that “straight” crude petroleum, of 
the right character and specific gravity, if properly handled, is 
harmless to the most tender varieties of fruit trees even when 
applied undiluted, and that it may be depended upon to kill the 
dormant scales when used undiluted or diluted with 60 or 75 
per ct. of water. 
While these experiments were supported in the main by those 
of Prof. Corbett, the experiments by Dr. Felt, although agreeing 

®‘New York State Museum Bul. 36 (Vol. 7), 
“Refers to the 20 per ct. emulsion. 
