138 
Mr. C. N. Ainslie, began experiments with a barrel pump, loaned by a 
market gardener. One plat was sprayed with 5 per cent kerosene 
emulsion; another with 10 per cent kerosene emulsion; a third plat 
with ordinary hard soap, 1 pound to 4 gallons of water; a fourth plat 
with whale-oil soap, 1 pound to 6 gallons of water. The spraying 
was done carefully, so as to reach every aphis possible. Upon 
examination the next day it was found that the 10 per cent emulsion 
and the hard soap had injured the plants. Not more than 50 per 
cent of the plant -lice were killed hi any of the experiments. On the 
loth of April the sprayings were repeated with similar results. All 
of the aphidids could not be reached, no matter how thoroughly 
the spraying was done. It was quite evident that unless the ground 
was almost soaked there would be little or no relief. These spray- 
ings cost at the rate of about $4 per acre. 
During the latter part of July it was found that Toxoptera was 
very abundant on the lawns of the Department of Agriculture at 
Washington, D. C. This outbreak became known to Mr. E. M. 
Byrnes, Superintendent of Experimental Gardens and Grounds, 
who at once had the entire infested block sprayed with a solution of 
one-half gill of blackleaf tobacco extract to each gallon of weak 
soapsuds. The application was, however, ineffective. Four days 
later a strip through this plat was thoroughly saturated with a 
strong solution of barnyard manure, made by soaking the manure 
in water. While there was no evidence that this killed any of the 
"green bugs,'' after nine days the pest was visibly less on this area 
than where the application of manure solution was not made. 
A series of experiments was then undertaken under the senior 
author's direction by Mr. E. O. G. Kelly, as follows: 
Tobacco dust was applied at rates of one-fourth, one-half, and 
1 pound to each 100 square feet, but after over a week had elapsed 
from the date of application no effect was to be observed and no dead 
insects were found. 
Kerosene emulsion was applied at S and 10 per cent strengths, 
and at the end of nine days no "green bugs" were to be found on the 
areas so treated. Also there was no perceivable injury to the grass. 
Whale-oil soap solutions, varying in strength from one-fourth of 
a pound to 2 pounds of soap to each 5 gallons of water, were applied 
to similar areas. In this case the stronger solution injured the 
grass slightly, but not permanently; in the case of the lesser strengths 
there was no injury to the grass whatever. The effect on the "green 
bug" was the same in every case. They were not only literally 
exterminated over the areas treated, but the applications seemed to 
protect from a reinfestation, in case of even the weakest solution. An 
examination five days after the application was made revealed the 
"green bugs" in myriads and breeding freely on the untreated space, 
while onlv 8 inches away and on the treated area living bugs were 
