SPRAYING PEACHES. 33 
nevertheless in the course of the work as practiced against the cur- 
culio, brown-rot, and scab noticeable good is accomplished. Although 
the spray is not strong enough to kill many of the adult scale insects, 
it is effective to an important extent in bringing about the death of 
the young scales. Experiments made by the Bureau of Entomology 
in the use of the self-boiled lime-sulphur wash as a summer spray for 
the San Jose scale! have shown that two or three applications will 
result in a marked improvement in the condition of the trees by fall. 
The effect of the wash is to prevent the settling of the young scales 
upon the twigs and branches, so that by the close of the season the 
trees are largely free from the insects. 
Further observations are necessary to determine just how much 
benefit will result from these applications in the control of scale 
insects, but it seems probable in peach orchards regularly sprayed for 
the curculio and for scab and brown-rot that the usual winter treat- 
ments for the San Jose scale may be reduced to perhaps one applica- 
tion every two or three years. Any observant orchardist should be 
able to determine for himself the necessity for winter treatments, 
depending upon the abundance of the scale insects. The lime-sulphur 
wash is furthermore effective against numerous other sucking insects, 
especially plant lice, which may be present on the trees. 
PREPARATION AND USE OF THE SPRAY. 
Spraying for the brown-rot, scab, and curculio does not differ in 
principle from the usual spraying practices. It is essential that an 
efficient spraying outfit be employed, so that the work may be done 
expeditiously and with thoroughness. Where the orchard interest is 
at all important it will be desirable to employ a power sprayer, such 
as a gasoline or compressed-air outfit. Excellent work, however, may 
be done with the ordinary barrel sprayer, which is suitable for orchards 
of a few hundred trees. In applying the spray, all parts of the tree 
should be reached. This is especially important in the first appli- 
cation, which is directed principally against the plum curculio. The 
purpose should be to coat thoroughly the foliage, twigs, and young 
fruit to insure to the fullest extent possible the poisoning of the 
beetles. The same precautions as to poisoning the foliage, fruit, and 
buds are also essential in making the second application, as the 
beetles are still very numerous, feeding and ovipositing freely. (See 
Table II.) This is also the most important application for the pre- 
vention of scab infection, which is prevented only by thoroughly coat- 
ing the young fruits. In subsequent applications the efforts should be 
directed more to coating the fruit with the spray to protect it from 
brown-rot infection, espeuially as it begins to ripen. 
1 Reported in the Journal of Economic Entomology, vol. 2, p. 130 
440 
