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i) 
perfectly safe for all kinds of trees and is very effective against the 
seale. With large trees or badly infested trees, preliminary to treat- 
ment it is desirable, with this as well as other applications, to prune 
them back very rigorously. This results in an economy of spray and 
makes much more thorough and effective work possible. The soap 
can be secured in large quantities at from 33 cents to 4 cents a pound, 
making the mixture cost, as applied to the trees, from 7 cents to 8 
cents a gallon. The success of the soap treatment is largely influenced 
by the quality of the soap used. Many brands are on the market, 
mostly made with soda lye. A potash soap should be insisted on, and 
one that does not contain more than 30 per cent of water. The soda 
soap washes are apt to be gelatinous when cold and difficult or impossi- 
ble to spray except when kept at a very high temperature. 
Kerosene treatment. —This consists in spraying the trees with ordinary 
illuminating oil (coal oil or kerosene). The application is made at any 
time during the winter, preferably in the latter part, and by means of a 
spray pump making a fine mist spray. The application should be made 
with the greatest care, merely enough spray being put on the plant to 
moisten the trunk and branches without causing the oil to flow down 
the trunk and collect about the base. With the use of this substance 
it must be constantly borne in mind that careless or excessive applica- 
tion of the oil will be very apt to kill the treated plant. The application 
should be made ona bright, dry day, so that the oil will evaporate as 
quickly as possible. Ona moist, cloudy day the evaporation is slow, 
and injury to the plant is more apt to result. If the kerosene treatment 
be adopted, therefore, it must be witha full appreciation of the fact that 
the death of the tree may follow. This oil has been used, however, a 
great many times and very extensively without consequent injury of 
any kind. On the other hand, its careless use has frequently killed 
valuable trees. Its advantages are its effectiveness, its availability, 
and its cheapness, kerosene spreading very rapidly and much less of it 
being required to wet the tree than of a soap and water spray. Pure 
kerosene is more apt to be injurious to peach and plum than to pear 
and apple trees, and the treatment of the former, as with the soap 
wash, should be deferred until spring, just before the buds swell. 
With young trees especially it is well to mound up about the trunk a 
few inches of earth to catch the overflow of oil, removing the oil- 
soaked earth immediately after treatment. 
The crude-petroleum treatment.—Crude petroleum is used in exactly 
the same way as 1s the common illuminating oil referred to above. Its 
advantage over kerosene is that, as 1t contains a very large percentage 
of the heavy oils, it does not penetrate the bark so readily, and, on the 
other hand, only the light oils evaporate, leaving a coating of the heavy 
oils on the bark, which remains in evidence for months and prevents 
any young scale which may come from the chance individuals that were 
