DISEASES OF PLANTS. 61 



were tested, all the sprayed vines receiving 4 applications of Bordeaux mixture, fol- 

 lowed with 3 of amnioniacal copper carbonate on 1 portion and the other with 3 

 applications of soda- Bordeaux mixture. In all about 12 acres of vines were sprayed, 

 at a cost of |7.10 per acre. The grapes from the unsprayed area were sold at $5.90 

 per acre, while the average return from the sprayed areas was $125.21 per acre. 

 Comparisons between the amnioniacal copper carbonate and the soda-Bordeaux mi>.x- 

 ture are drawn, from which it ajipears that the soda- Bordeaux mixture is to be pre- 

 ferred to the other. A warning is given against the use of eau celeste, as it is not as 

 etticient as the other fungicides and frequently causes injury to the foliage. In con- 

 tiiuiation of the experiments in 1900 on the number of sprayings recjuired, the 

 results obtained were more or less conflicting. The sprayings should, as a rule, be 

 made at weekly intervals from the close of the flowering period until there is no dan- 

 ger from loss. As a rule, from the experiments which have been conducted by the 

 station, the author thinks that it is demonstrated that grape rot, which has almost 

 destroyed the grape industry in parts of Ohio, may be prevented, and that the future 

 for the grape growers is nuich brighter than for a number of years past. Directions 

 are given for the making of the soda-Bordeaux mixture and for the testing of the 

 caustic soda which is used in its j^reparation. 



Tlie relation of grape spraying to public health, A. T>. Selby {OhioSta. Bui. 

 ISO, pp. 4~-4<^)- — At the suggestion of the State Dairy and Food Commissioner of 

 Ohio, the author has prepared a statement relative to the use of fungicides as affect- 

 ing public health. A number of analyses were made of grapes which had been 

 thoroughly sprayed in the experiments for control of the grape rot, and the highest 

 amount of copper oljtained was 0.0004 gm. to 100 gm. of berries. This amount was 

 so small as to be hardly worth consideration. The effect of copper compounds on 

 wine fermentation is commented upon, the author (juoting from foreign authorities 

 which show that there is no danger to be apprehended, the fermentation either 

 removing the copper or rendering it insolul)le and without any importance in wine. 

 An experiment was conducted with sprayed grapes in which jelly was made from a 

 lot of grapes which had been heavily sprayed and which would ordinarily be rejected 

 in the market as improperly sprayed. One hundred gm. of grapes and stems 

 contained 0.00084 gm. of copper. When made into jelly 100 gm. of the incinerated 

 jelly yielded 0.00018 gm. of copper. The grapes in this case were very ripe and both 

 the grajjes and stems were cooked together. Had the green berries been used or the 

 stems removed the amount would have been much smaller. 



The meteorological conditions requisite for injurious fungi, K. Sa.to {Frome- 

 tJu'iis, IS {1901), Noa. GS3, pp. 1S£-135; 6S4, pp. 154-157).— The relation existing 

 between outbreaks of powdery mildews, Peronospora, white rot, etc., and the atmos- 

 pheric conditions are pointed out. The direction of long-continued winds is said to 

 aid materially in spreading these diseases. The observations cover the period from 

 1895 to 1901. 



Experiments with the fungicide sulfurin, K. Mohr {Ztschr. Pflanzenkrank., 

 11 (If'Ol), Xu. 2-3, pj). US, 99). — Tills fungicide, which has been highly recommended 

 for use in protecting grapes against the powdery and downy mildews, is said to be 

 calcium disulphid. This material the author has tested in connection with a number 

 of diseases, and, based upon 10 years' experiments, he strongly recommends it for the 

 prevention of the powdery and downy mildew of grapes, grape anthracnose, peach 

 curl, and apple and pear scat), as well as a number of diseases of roses and other 

 plants. 



The meteorological conditions for the development of mildews, K. S.\jo 

 (Ztschr. Pjianzenkrank., 11 [1901), No. £-S,, jip. 9:3-95). — It is said that the powdery 

 mildew {Oidium tuckeri) made its appearance in a certain part of Hungary in 1899, 

 and the downy mildew {Peronospora vitirola) in 1900. The meteorological conditions 

 for both years from April to August are shown, from which the author concludes 



