120 
About the 1st of July a new brood appeared in comparatively limited 
numbers from the few larvae which escaped the spring treatment. The 
application of kerosene was repeated on July 7 as in the first instance, 
and a similar result followed, with the exception that it seemed to have 
been even more effectual, and no living scales whatever were discov- 
ered when the trees were examined on the 17th and at various later 
dates, even in a few instances where the young had remained under 
the old scales. The above experience indicates that we have in this 
new peach scale an insect very amenable to summer treatment. 
Chionaspis euonymi Comst. has proven troublesome to the Euonymus 
trees on the Department grounds and in pri%vate yards in the city of 
Washington. Applications of kerosene emulsion have been made from 
time to time to eradicate the pest. When these applications were made 
ust at the time of hatching fairly good results followed, but the diffi- 
culty has always been that the hatching period of this scale extends 
over a number of weeks, and later in the season the broods become so 
intermingled that all stages are found on the plants together. The 
ordinary washes are totally ineffective on half-grown or mature insects 
of this species. The experiments already referred to show that it takes 
a strength of kerosene emulsion four times greater than that ordinarily 
recommended to kill the adults, and this can be applied to the plants, 
at least in their mature and midsummer condition, without injury. 
Applications made on July 18, on a scorching hot day, were not fol- 
lowed by rain for four days. Double ordinary strength, namely, 1 part 
of kerosene to 4£ of water, resulted in the death of 75 per cent of the 
adults. Four times ordinary strength, or diluted with 2^ parts of water, 
resulted in the death of 99 per cent of the adults and young. The ordi- 
nary strength, nine times diluted, killed nothing but the newly-hatched 
young. 
Experiments were also tried on the oak scale, Asterodiaspis quercicola 
Bouche, the young of which began to appear early in May. The worst 
infested oak was, at the time of treatment, just expanded into full leaf, 
and the foliage was excessively delicate and tender. The application 
was therefore made only at the rate of 1 part of the emulsion to 13 
parts of water. This resulted in the death of all the young which had 
emerged at that time. This scale, however, is one of those the hatching 
of which extends over a considerable time, and several applications are 
necessary to reach complete extermination. Similar results attended 
the spraying for Chionaspis furfurus on Japan quince. In the case of 
this insect, however, the emergence of the spring brood is more uniform, 
and one or two applications are sufficient. At Washington the young 
of this scale emerge during the second week in May, and the applica- 
tion is best made about the loth. The abundant leafy growth of the 
Japan quince makes it very difficult to wet the branches with any 
thoroughness, and midwinter treatment for this plant will ordinarily be 
necessary. 
