58 
and vigorous peach, pear, cherry, and apple trees, euonymus bushes, 
and some old bearing peach trees, were thoroughly sprayed with pure 
kerosene early the past spring, with one exception, before the buds had 
begun to swell. In the case of two large bearing peach trees the 
blossom buds were swelling and opening and these trees were also 
badly infested with Diaspis lanatus. The other plants, with the excep- 
tion of the euonymus bushes, were healthy and free from all insects. 
Much to my surprise and astonishment, noill effects of any moment 
resulted in the case of any of the trees sprayed with kerosene. Inthe 
case of all the trees spraying was continued just long enough to mois- 
ten the plants thoroughly, but not to cause the oil to run down the 
trunks and collect about the base, and with the young trees the soil 
was carefully mounded up and pressed about the crown to avoid all 
danger of the oil collecting at that point. 
The pear trees treated, and also the peach, came out in full bloom, the 
opening of the blossom buds not being at all interfered with by the oil 
bath. After the bloom fell the peach trees treated with pure oil made 
much finer growth than untreated trees. This may have been in part 
due to the more favorable location of the trees, and possibly also to the 
fact that in the treatment with the coal oil the eggs of Aphides on the 
trees had been entirely killed, whereas on the untreated trees a very 
bad infestation with plant lice developed early and checked the growth 
of the trees, killing some of them. No Aphides, however, appeared on 
the sprayed trees. In the case of the pear trees particularly, and also 
the apple, the unfolding of the leaf buds was very noticeably delayed 
as compared with untreated plants, the buds seeming to open up much 
more slowly, and for two weeks at least the difference was very marked. 
Very soon thereafter, however, the treated trees overtopped the others 
both in abundance of foliage and amount of new growth, and at the 
present writing, July 20, there seems to have been no injury whatever 
as a result of the treatment. 
The large peach tree sprayed showed no ill effects, and all of the 
scales on the tree were killed except where they had been protected in 
a few instances by masses of leaves webbed about the limbs. At least 
99 per cent of the scales were killed. On the euonymus a similar result 
was Shown, at least 99 per cent of scales having also been killed by 
the oil. 
These results are so greatly in contrast with those previously attained 
in the experiments conducted in practically the same way that it seems 
difficult to account for them. That spraying with pure oil will often 
kill trees can not be doubted, even when applied in the dormant condi- 
tion in winter, as demonstrated by experiments on a number of apple 
and peach trees two or three seasons ago. It is possible that with these 
earlier experiments the same care was not employed to prevent the 
collection of oil about the trunks of the trees and the trees were not 
mounded up, but the work was as carefully done as would ordinarily 
