Professor Cook has varying results with spraying for the curculio. He finds that the insect is destroyed when rains are infrequent, but frequent showers wash the poison from the smooth fruits. He finds carbolized plaster a good remedy also, under like conditions. This is prepared by stirring one pint of crude carbolic acid in fifty pounds of plaster. This powder is thrown freely over the trees. Professor Cook makes the following conclusions : " The arsenites and carbolized plaster will protect against the plum curculio if they can be kept on the tree or fruit. But in case of very frequent rains the jarring method will not only be cheaper, but much more effective. Again, as our wild fruits are more cleared away we must have plums in our orchards to protect the apples from the curculio. When apples are seriously stung they become so gnarled and deformed as to be worthless. It will pay, then, to set plum trees near by or among the apple trees. Then we will escape mischief among our apples from the curculio, and will only need to spray our apples once, 'to destroy the codling moth, and can treat the plum trees three or four times with pans green or carbolated lime in case we have only occasional showers, or can jar the trees when the rains are very frequent.

For the apples we can use london purple, one pound to 200 gallons of water. For the plums we must use paris green, one pound to two or three hundred gallons of water." We suggest to Professor Cook that he add kerosene emulsion to the arsenite mixture to increase its adhesiveness.

Great injury to foliage has been reported from many parts of the country from the use of london purple, particularly upon the peach. Professor Cook made many experiments to determine the cost of this injury, and his conclusions are these: "London purple is more injurious to the foliage than is paris green ; and white arsenic - arsenious acid - is more harmful than is either london purple or paris green. This is doubtless owing to the soluble arsenic which is quite abundant in london purple, and almost absent in paris green." 2. "Peach foliage is especially susceptible to injury, and cherry foliage the least so of any of the kinds treated." 3. "It would seem that london purple and white arsenic, used just before a rain, are more harmful than when used during a drought. We not only saw greater injury when a rain followed spraying within two or three days, but secured the same results by spraying soon after treatment with pure water. This also accords with the view that the injury comes from the presence of soluble arsenic." 4. "It would seem that spraying soon after the foliage puts out is less harmful than when it is delayed a few days; or better a few weeks." 5. "London purple may be used on apple, plum, cherry, pear and most ornamental trees, but on these should never be stronger than one pound to two hundred gallons of water.

If the application is to be repeated, as it must be for the curculio to prove effective, or if it is to be used in June or July, paris green should be used in the same proportion as above, or else we should use only one pound of london purple to three hundred gallons of water. I now think that this necessity is more due to time of application than to the fact of increased quantity of the poison." 6. "If the arsenites are to be used on the peach to defend against the curculio, paris green only should be used, and that not stronger than one pound to three hundred gallons of water." 7. "The injury done to the foliage is never immediately apparent. It usually shows somewhat the second day, but the full injury is frequently not manifest till the fifth day, and often not till the tenth".

Arsenities and Carbolized Plaster for Curculio.

Arsenites and foliage.

The bulletin details experiments to determine if sufficient poison falls upon the grass under heavily sprayed trees to cause injury to stock. Samples of grass were analyzed and others were fed to a horse; both the chemist and the horse declared that the poison was not sufficient to cause damage - an interesting conclusion.

Professor Cook recites instances of heavy loss to beekeepers in neighborhoods where orchard-ists sprayed their trees while in bloom. The adult and immature bees were alike killed. This destruction of bees is entirely unnecessary, as there is no occasion whatever for spraying trees when in bloom.