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MR. J. H. HALE of Georgia and Connecticut, the greatest grower of peaches in the world, commanding over 1,000 acres of orchard, paid his respects to the brown-rot in the following terms: "The brownrot is so great a factor for evil in the raising of peaches for the market that in a few years more it would have accomplished the complete failure of my orchard plant in the state of Georgia. We can master or control every other enemy of the peach by up-to-date methods and precautions but until now we have had no weapon that would touch the brown-rot fungus." And then he continued to say that, "The use of the self-boiled lime-sulphur spray, as a foliage treatment for the peach-tree, recently discovered by Mr. W. M. Scott of the U. S. Department of Agriculture, alone would swing the future status of my fortune from failure to success."
In the spring of 1909 Mr. Hale offered the orchard of the Hale Georgia Orchard Co. at Fort Valley, Ga., as a demonstration and proving ground of this spray
mixture of the usefulness of which Mr. Scott was then pretty well convinced. Experiments on small plats had been made in 1907 and 1908. While the great plant of the Hale company had had the best of care and was otherwise in good condition, it had in recent years become so infected with brown-rot that in 1908 the crop was largely lost.
Two other enemies of the peach were allied with the rot to encompass the ruin of the orchard, namely, the scab and the plum curculio. The former is also a fungus but of not so malignant a type as the brown-rot. It serves as an accomplice to the latter by cracking and spotting the fruit thus giving the deadlier fungus an easy entrance. The curculio beetle damages the peach by puncturing the fruit for the purpose of laying its eggs within the skin. It is a troublesome creature but its rate of speed as a worker of destruction is to that of the brownrot as a slow-match to a prairie fire. Its worst crime is in making the punctures that give the rot free entree.
Mr. Scott and his chief assistant, Mr. Willard Ayres, conducted the spraying in large blocks of different varieties comprising over 5,000 trees, while Mr. Hale's force sprayed about 7,000 trees in their orchard under the supervision of the two scientists. Plats of trees were selected, trees counted and sprayed while next a sprayed plat another was left unsprayed. Two applications of spray were made, one about a month after the petals dropped and again three weeks before the fruit ripened. At picking time the entire crop including dropped fruit was counted on five average trees in each plat. On the sprayed plat it was found that 17% was affected with brown-rot, and that in 93% of the rotting fruit infection had been admitted by curculio punctures. The scab was, from the commercial point of view completely controlled. On the unsprayed plat 49.5% of the fruit
was affected with rot, and 91.5 with scab. 81% of the rot infection had happened through curculio punctures. The figures themselves were very satisfactory to Mr. Hale but there was another cause for gratification in the increased size and color and generally better merchantable condition of the sprayed fruit. The commercial results of the spraying were determined by counting the marketable fruit on 500 trees from each plat. The sprayed plat yielded 170 crates, the unsprayed but 80. Thus was nearly a quietus given to the brown-rot. The curculio was the factor that held the door open.
To offset curculio injury some experiments were made in cooperation with Mr. A. L. Quaintance of the Bureau of Entomology of first spraying with
DIFFERENCE IN BROWN ROT DEVELOPED IN SPRAYED AND UNSPRAYED PEACHES. 1 Two crates ol Elbcrta poaches after six days in refrigerator car and a day in express car. The fruit on the left had
been sprayed: that on the right had not.
arsenate of lead just as the calyces were shedding;, and again in about three weeks with self-boiled lime-sulphur plus lead arsenate. The success was brilliant. Only 4.5% of the fruit showed brownrot, 6.5'/< had slight traces of scab, and about 27.5% were curctilio punctured. On the unsprayed plat 639? was rotted, 99% scabby, and 97% was wormy from curculio. The sprayed block yielded 327 crates of first class fruit while the unsprayed block yielded but 33 crates, all of which were poor in quality. In the New York market the sprayed fruit brought fifty cents more per crate than the unsprayed, and all of it was sold before the other, showing the impression made upon the buyers by the difference in the appearance of the two classes.
The principal reason why, until Mr. Scott's discovery, the disease had enjoyed immunity was that, so far as was known, there existed no spray that could be safely applied to the peach tree while in full leaf. All the peach-grower could do toward controlling the fungus was to gather the dropped infected fruit and burn them. As it was quite impossible to do this cleanly and as a few of these "mummies" overlooked was enough to infect an orchard, the laugh was generally with the "mummy."
The self-boiled lime sulphur spray in which the mixture was boiled by the slaking of the lime was a discredited spray for San Jose scale treatment. Mr. Scott after trying about all the combinations of lime and sulphur finally reached the conclusion that the excess of the
caustic sulphids in the boiled mixture caused the scalding of the peach leaf and he turned as a last resort to the expedient of self-boiling as bringing into solution a minimum percentage of sulphur.
The theory about the action of this new spray is that the free lime serves as a matrix to hold all the other elements together, that there are enough of the sticky sulphides to bind the solid materials to the fruit, branches and leaves, and that the finely divided sulphur deals personally and correctively with the bad fungus.
While brown-rot does its worst in humid regions such as the early peach belt of Georgia, it is to be feared in every peach section of the country, with the exception of the arid irrigated localities of the west. As a general thing the disease does not fall to work until the fruit is nearly mature.
A typical and singularly complete case of rot destruction occurred near Dublin, Georgia, a few years ago. It was the year of the first full crop the orchard had borne and all went fairly until harvest time. Figuring on his masses of large handsome fruit the owner ordered crates for 40 carloads. Then came days of muggy air and drizzling rain, and with them a spontaneous combustion of brown-rot. Out sprang the brown spots wearing their beards of white sporebearing threads. The pickers were hurried to cull the best of what was left but it was too late. The disease continued to develop in transit and an entire crop
that was easily worth $20,000 was a total failure and the owner was in debt. The career of this disease had practically doomed the early peach belt of Georgia to extinction when Mr. Scott intervened.
The annual loss to the peach crop due to the ravages of brown-rot is estimated at $5,000,000. The normal output of the state of Georgia is not less than 5,000 carloads, worth about $2,500,000. In 1900 the brown-rot burned up between $500,000 and $700,000 of the peach profits of that state. A conservative estimate of the annual damage in Georgia in recent years is $1,000,000. It is good to know that the peach grower now has the whip-hand of so expensive a disease.
State Bank, South Dakota, hit upon the idea that if he could place a bottle of some strong chemical between the outer and inner doors of the vault its fumes might retard the work of safe breakers or perhaps frighten them away. A quart bottle of formaldehyde was immediately given a position as a silent night watchman between the doors of the vault.
For about five years the ."yegg doctor" kept unobtrusive guard. Finally early in November. 1910, the test came. A couple of professional cracksmen entered the town. Two charges of nitro-glycerine were used on Cashier Clark's safe that night. The first one did little damage but the second wrecked both the outer and inner doors, tore the latter from their hinges and threw them out into the vault and against the small safe and safety deposit boxes. The "yeggmen" did not wait to wreck the inner safe, however, for at the same moment the "yegg doctor" responded to. a hurry call and the fumes of a full quart of formaldehyde filled the room. Choking and gasping, with tears streaming from their eyes, the criminals scrambled out the way they had come in and left tracks down the peaceful country highway that fairly sizzled. For days after the explosion the fumes of formaldehyde were so strong that a person could not breathe in the vault.