540 JOURNAL OF THE KOYAL HORTICULTURAL SOCIETY. 



plates). — Black rot of Grapes due to the attack of the fungus Guignardia 

 Bidwellii causes great loss to grape-growers in the States. Leaves, young 

 shoots, and fruits are all attacked. If the fruit is attacked when very 

 young it turns black and soon drops off, if later, the disease appears as a 

 whitish spot on the fruit, which increases in size till the berry shrivels 

 and becomes covered with the minute black fruits of the fungus. In 

 some cases the berries rot rapidly and become soft. On the young- 

 shoots numerous small, reddish brown spots appear as the result of the 

 attack of the fungus. 



Infection comes in the spring, probably from the winter spores on the 

 old black-rot mummies, and it is desirable that all the infected wood and 

 decayed berries should be pruned away and destroyed by fire as early as 

 possible. Spraying with Bordeaux mixture will then very greatly reduce 

 the amount of disease. Several formulae for the making of Bordeaux 

 mixture were tried and the most effective was found to be 



4 lb. copper sulphate 



3 lb. quick (unslaked) lime 



50 gallons water. 



when spraying was commenced at the time the young branches were 

 eight inches to twelve inches long (no benefit followed earlier spraying) 

 and repeated at intervals five or six times. A good non-staining spray 

 was made by dissolving 1 lb. neutral copper acetate in 50 gallons water, 

 and this was excellent for a final application. Lime- sulphur preparations 

 have not been sufficiently tested to determine their value. Thorough 

 application, at the proper time, with correctly compounded sprays made with 

 pure materials only, gave the best results and sometimes reduced the 

 amount of rot to 1 per cent. — F. J. C. 



Grape-gTOWing\ By 0. B. Whipple (U.S.A. Exp. Stn., Colorado, 

 Bull. 141 ; April 1909). — This deals fully with the cultivation of grapes 

 in the peculiar climatic conditions of Colorado, from the preparation of 

 the soil for planting to the packing of the fruit for market. One obser- 

 vation of possibly general interest is the superiority in flavour, sugar 

 content, and travelling qualities, of the fruit from vines which are allowed 

 to become dry at the roots during the ripening process. — A. P. 



Grape-growing- in New York. By M. J. Dorsey ( U.S. A. Exp. Stn., 

 New York, Bull. 315 ; March 1909).— The author discusses the natural 

 factors influencing grape culture, such as location, soil, climate, &c, and 

 the position of the principal grape districts in this respect. A brief 

 description of the most important species of Vitis is given, together with 

 a table of 161 varieties, showing their size, colour, flavour, season, use, 

 fertility or sterility of blossom, &c, with short notes on their commercial 

 value. — A. P. 



Grape Rot, due to Pestalozzia uvicola Speg. By F. A. Wolf 

 (U.S.A. Exp. Stn., Nebraska, 1908; with fig.).— This disease was first 

 ored in Italy in 1877, and has now appeared in Nebraska on ripe 

 grapes. The first time it has been recorded out of Europe.— M. C. G. 



