52 EXPERIMENT STATION RECORD. 



Observations were made on the possibility of preventing discolored potatoes 

 from rotting after digging, and it was found that where the discoloration was 

 due to the presence of a fungus nothing could be done to stop the rot. Inhere 

 appears to be little indication that the disease spreads in the soil after ripening, 

 and on this account it is reconnnended that potatoes rotting in the ground should 

 be left as long as the season will permit before digging. 



Notes are given on tomato spraying, in which Bordeaux mixture was applied 

 on different dates for the prevention of leaf spot, and while the treated vines 

 remained green until frost, no data relative to the weights of fruits or yields 

 were kept. In another series of experiments the plants were given 5 applica- 

 tions of Bordeaux mixture, and the yield of sprayed and unsprayed plants is 

 shown in tabular form. In every case the yield from the si)rayed plants was 

 largely in excess of that from the unsprayed ones. 



In a previous publication of the station (E. S. H., 1('>. p. (>(j) an account is 

 given of spraying cucumbers for the prevention of blight. These experiments 

 have been continued, and as the result of 3 years' work with Bordeaux mixture on 

 cucurbits it is shown that there was a decided inci'eaee in yield for the first and 

 third years, when the downy mildew was present, and a decided decrease the 

 second year, when no fungus was troublesome on the plants. This showing 

 raises the question as to whether it pays to spray melons and cucumbers, and 

 in the absence of knowledge relative to the probable occurrence of disease, it 

 would doubtless pay to spray the plants or at least to be prepared to give 

 thorough spraying on the first appearance of disease. 



Potato spraying experiments in 1905, F. C. Stewart. II. J. Eustace, and 

 F. A. SiKRiNE {NeAV York Slatr Sta. Bill. 279, pp. 153-220. pl-i. 5. map 1). — A 

 report is given of the fourth j'ear's experiments in ijotato spraying carried on 

 by the authors in the lO-year series of experiments which have been previously 

 described (E. S. It., 14, p. 875 ; 15, p. 781 ; 17, p. 4G). 



During 1905 the experiments carried on by the station at Geneva gave an 

 increase of 119J bu. per acre when the plants were given 5 sprayings and 107 bu. 

 when given 8 sprayings. At Riverhead, on Long Island, the gain due to 5 

 sprayings was 82 bu. per acTe and to 3 sprayings 31J bu. At this place the flea 

 beetle was the chief enemy of the potato. 



In what are called the farmers' business experiments, in which jiotatoes were 

 sprayed under the direction of the station officers, in 13 experiments, including 

 166S acres, the average gain due to spraying was 4Gi bu. per acre, the cost of 

 spraying .$4.25 per acre, and the average net profit .$20.04 per acre. In 50 

 volunteer experiments, including 407 acres of potatoes, the gain due to spraying 

 was 593 bu. per acre, and the average net profit in 29 of the experiments was 

 $29.85 per acre. 



In comparative tests of the efficiency of soda Bordeaux and lime Bordeaux 

 mixture the rows sprayed 4 times with lime Bordeaux yielded at the rate of 9 bu. 

 per acre in 1 test and 35 bu. per acre In another test more than similar plats 

 sprayed with soda Bordeaux. The addition of Paris green or arsenate of soda 

 to Bordeaux mixture can be performed without any danger of injury where used 

 in moderate amounts. 



During 1905 in unsprayed fields the loss from blight, rot. and flea beetles was 

 estimated at 50 bu. per acre. The experiments conducted by farmers in the past 

 3 years have shown net profits due to spraying of .$22.79 per acre. 



The authors reconnnend I)eginning spraying when the plants are to 8 in. 

 high and repeating it throughout the season at intervals of 10 to 14 days, or 

 until 5 or (i aiiplications have been given the plants. When bugs are trouble- 

 some Paris green or other poison may be added. 



