RESUMÉ OF RESULTS, AND CONCLUSIONS FROM THEM. (1) The sulphur solution did not have a sufficiently marked effect to make its application profitable. (2) Sodium hyposulphite: If this is used at the rate of 1 pound to 12 or 15 gallons of water it does not injure the foliage, and as its cost is slight its benefit would be sufficient to more than repay the cost. It is easily washed off, however, and the copper mixtures would be found more effective and cheaper in the end. (3) Potassium sulphide: This gave slightly better results than the hyposulphite, but it is more expensive and should be passed over for the same reasons. (4) Ammoniacal copper carbonate: This is one of the easiest of all the mixtures to prepare, and its effects are comparatively lasting. It is slightly cheaper than the next, but it seems to have rather less effect. It showed itself, however, a valuable remedy, but on account of its slightly injurious effect on the fruit the formula will be improved by substituting 28 gallons for 22. (5) Modified eau celeste: The best results were obtained with this mixture and with varieties likely to scab it will prove a good investment. Thirty or 32 gallons of water should be used where the formula calls for 22. By its use a difference in the amount of scabby fruit of from 50 to 75 per cent. can be produced, and with such varieties as Fameuse and Northern Spy it will often make all the difference between success and failure. The injury to the skin of the apple merely gives them a russet color in streaks and in no way has an appreciable effect on the size or shape of the fruit. Whether it injures the appearance of the fruit might be questioned. In addition to the experiment recorded above, several trees received one and two applications soon after the fruit set, and others were sprayed on the 25th of July and the 1st of August. No effect was appreciable except in the cases where the copper solutions were used on the trees in May and June. From the experience of this year, we are convinced that with many varieties in localities where scab prevails either of the copper mixtures will add from 25 to 50 per cent. to the value of the crop at a cost not exceeding 25 or 30 cents for an average-sized tree. This estimate will cover the cost of the chemicals and of their application, and if the season is a warm, dry one, and the chemicals are purchased at wholesale, it can be reduced one-half. TREATMENT OF BITTER-ROT OF THE APPLE. By GEO. G. CURTISS. SIR: I have the honor to submit herewith my report on experiments made the present season under your direction in the treatment of bitter-rot of the apple. Respectfully, GEO. G. CURTISS, B. T. GALLOWAY, Chief of the Section of Vegetable Pathology. The experiments were commenced too late in the season to be as successful as they would have been if undertaken earlier and if I had been better equipped with apparatus for the purpose. The formulæ used were, first, potassium sulphide solution, ounce to gallon of water; second, ammoniacal copper carbonate solution. To 1 quart of aqua åmmonia (strength 22° Baumé) add 3 ounces of copper carbonate, agitate rapidly a short time, when it will dissolve, forming a clear liquid. Dilute with water to 22 gallons. I found a large fruit jar (half gallon) best to dissolve the copper carbonate in on account of the escaping fumes of ammonia. With the imperfect apparatus at command (the Lewis combination force-pump) it took 2 gallons per tree of moderate size. With a good implement less would be required. The potassium sulphide cost 30 cents per pound, making cost of solution for each spraying 3 cents per tree. The cost of ammoniacal copper carbonate, 22 gallons, is 26 cents, or about 2 cents per tree. August 18, I sprayed with potassium sulphide solution one tree each of Abram, York Imperial, Fallawater, Fall Pippin, and Limbertwig. Their condition at time of spraying was, Abram fully one-half plainly showing the infection; York Imperial, Fall Pippin, and Limbertwig from 5 to 10 per cent. affected, and the Fallawater fully 90 per cent. af |