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REPORT OF THE CHIEF OF THE DIVISION OF VEGE

TABLE PATHOLOGY.

SIR: I have the honor to submit herewith my annual report for the year 1890. As heretofore, the report embodies only a brief summary of the work accomplished in this Division during the year, the details having been published in various bulletins and circulars already issued. Respectfully,

B. T. GALLOWAY, Chief of the Division of Vegetable Pathology. Hon. J. M. RUSK,

Secretary.

WORK OF THE DIVISION.

GENERAL BUSINESS.

Under this heading may be mentioned care of correspondence, preparation of bulletins and circulars, work on the herbarium, indexing literature, and properly classifying and filing the same.

During the year nearly three thousand letters were received and answered, this work consuming fully one third of my own and assistants' time. The writing, indexing, filing, and general care of the letters requires nearly the whole time of two clerks.

Since my last report the Division has published, in addition to the regular annual report, one special bulletin and four numbers of THE JOURNAL OF Mycology. The special bulletin contained 120 pages and embodied the results of experiments made in 1889 in the treatment of plant diseases. The JOURNAL contains numerous papers, both scientific and practical, and as an important means of quickly and effectively disseminating information I can not conceive of any. thing more useful. During the year the edition was increased 500, but such has been the demand for it that every number but the last is now exhausted.

The general care of the herbarium requires the work of one assistant, while indexing, filing, and general supervision of the literature consumes a considerable part of the time of another.

The force practically remains the same as last year, the assistants being Miss E. A. Southworth and Mr. D. G. Fairchild. Erwin F. Smith is still in charge of the peach yellows investigation and Newton B. Pierce of the California vine disease. Pear blight and several other diseases have received attention at the hands of Mr. M. B. Waite.

LABORATORY WORK.

During the year the principal diseases under investigation in the laboratory were pear blight, a bacterial disease of oats, sweet potato diseases, anthracnose of the cotton and hollyhock, peach yellows, the California vine disease, pear scab, cherry leaf blight, grape diseases, and diseases of greenhouse plants, particularly of the carnation and violet.

A new disease of the grape appeared the latter part of September in several parts of New York State. The matter was investigated by Mr. Fairchild and found to be a malady which has been known for some time in certain parts of Europe. The disease manifests itself in the form of red or purplish spots on the leaves, the latter soon becoming brown and withered, and finally falling, leaving the fruit to shrivel or else mature imperfectly. In Mr. Fairchild's report, which was published in THE JOURNAL OF MYCOLOGY, Vol. VI, No. 3,

the disease is fully described, its causes pointed out and suggestions made in regard to preventing it.

In connection with the laboratory work on pear blight Mr. Waite visited Georgia during the months of February, March, and April, making, while there, a series of field tests with fungicides, and also collecting such data as only field investigations render possible.

The work on peach yellows and the California vine disease is given more in detail under their respective headings.

FIELD EXPERIMENTS,

A special effort has been put forth during the year to make the field experiments as thoroughly practical as possible. With this end in view I have spent considerable time in the field myself and have also kept one or more of my assistants constantly engaged in work of this kind. I am more than satisfied with the results of the work, as we have been able to obtain facts which would not have been possible had we depended on field agents exclusively.

I believe that to obtain the best results in practical experiments, such as we are conducting, we must either do the work ourselves or place it in the hands of men having a thorough knowledge of plant diseases. Such men, with possibly here and there a rare exception, are as yet to be found only in some of our experiment stations; it is by coöperation with these that we are able to secure the very best results at comparatively little expense to the Department and practically none to the Stations. Our coöperative work this year with the Wisconsin Station has proved eminently satisfactory, both to us and the Station, and the expense to both has been less than half what we usually pay for field agents.

EXPERIMENTS NEAR WASHINGTON,

This work was conducted wholly by myself and assistant, Mr. D. G. Fairchild, the diseases under treatment being black rot of the grape, pear leaf-blight, and pear scab.

Treatment of black rot of the grape. For this experiment a vineyard belonging to Capt. J. 0. Berry, situated 12 miles southwest of Washington, was selected. The vineyard consisted of about one thousand Concord vines, sixteen years old, and trained to stakes 8 feet high. It had not borne a pound of fruit for several years on account of rot, thus furnishing the very best means of thoroughly testing the value of the fungicides.

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The vineyard was divided into five plats, as shown in the aocompanying diagram. The diagram also shows the number of vines in each plat and the treatment it received. The experiment was not made to discover a remedy for black rot, for this question had been settled already. The main object of the work was to determine, if possible, (1) the best means of applying the fungicides; (2) the relative value of the fungicides mentioned in the diagram, and (3) the amount of copper found at the close of the season on fruit treated with the Bordeaux mixture. Each plat was sprayed eight times, first on May 1, and afterwards at intervals of fifteen days, except the last treatment, which was made at the expiration of twenty days.

As regards vigor of vines there was considerable difference in the various plats, hence it was not expected that the yield for each division would be uniform, even if all were treated alike.

In applying the fungicides three spraying machines were used, namely: the Eureka, the Japy, and Nixon's Little Giant. The Eureka and Japy pumps are of the knapsack pattern, while the Nixon is a cart machine holding 40 gallons. It is drawn by hand and is provided with two hose connections, an agitator for keeping the liquid stirred up, and 16 feet of hose. After a thorough trial of all of the machines the Little Giant was selected as the one best suited to our wants. With it we were able to treat four rows at a time, doing the work as thoroughly and rapidly as we could spray two rows with the knapsack pumps.

There is no doubt that, in certain situations, such as on steep hillsides, where the vines are trellised, the knapsack pumps will be found to work to the best advantage. Also where a person has only a small vineyard, of say, not more than 3 or 4 acres, such a pump will be all that is required. For large vineyards horse-power machines should be used. Some of these pumps drawn by two horses and worked by two men and a boy will spray an acre of vines in thirty minutes.

In all cases we used the Improved Vermorel nozzle and lance and we can say without hesitation that for our work we have not been able to find anything better.

As to the relative value of tbe treatments, cost, etc., a full account

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