22 
JST. C. Agricultural Experiment Station 
Remedies. The standard remedy for the gloomy scale is to spray the 
trees thoroughly (Fig. 15) once each year, either late in the winter 
or early in the spring, with a mixture composed of one gallon soluble 
oil to eight to ten gallons of water. The soluble oils, which are sold 
under a variety of trade names, are heavy oils that make a milky emu - 
sion when mixed with water. This mixture when sprayed on the tiees 
kills only the scale insects that it touches, hence it is necessary that 
spraying of this kind be done very thoroughly and that care be taken to 
cover every limb and branch. Care must also be taken not to get any 
more of the spray mixture on the trees than is absolutely necessary, 01 
oil injury lias been reported on sprayed maples in other states, althoug 
it has never been noted in this State. The number of times it wi e 
necessary to spray maple trees will depend upon a number of factors, 
chief among which are the amount of infestation and the care with 
which the spraying is done. Obviously a tree that is heavily infested 
will require more spraying than a tree that is only lightly infested. On 
the other hand, one careful spraying is the equal of two or more careless 
sprayings. Hence we set a standard of one spraying each year, and 
departures can be made from this standard as the case seems to demand. 
Sprayings with strong oil solutions can be made only during the dor¬ 
mant life of the tree, that is, from the time the leaves are shed m the fall 
until the buds commence to swell in the spring. Apparently, sea e 
insects are more susceptible early in the spring just at the time the buds 
are commencing to swell, and this is the most effective time for spraying. 
Summer sprayings are not successful against this pest because mixtures 
strong enough to kill the adults cannot be used without injuring the 
trees and the young are produced over such a long period that no reme y 
can be used against them successfully. Scraping, painting or white¬ 
washing or scrubbing the trunks and larger limbs of infested trees is oi 
very doubtful value, for the insects occur on the smaller limbs and 
branches in such numbers as to seriously damage the trees. 
