DISEASES OF PLANTS. 51 



cides containing larger quantities of copper sulphate or lime. Five or 6 appli- 

 cations, beginning when the shoots were about 8 in. to 1 ft. long, generally gave 

 as good results as where 1 or 2 additional earlier applications had been made. 



Where unsprayed grapes were a total loss from black rot in 1907, the rot on 

 the sprayed plats was reduced to 28.3 per cent. The next season, 1908, when 

 the rot was almost equally destructive on the unspi*ayed plats, on the sprayed 

 plats it was reduced to less than 1 per cent, apparently showing a cumulative 

 effect of treatment for the two seasons. 



The experiments have shown the necessity of covering the vines thoroughly 

 with a fine si)ray of properly prepared Bordeaux mixture, and where the black 

 rot is serious or the foliage very keavy it is found desirable to use trailers 

 attached to the spraying apparatus and have the nozzles directed by hand, so 

 as to properly cover the foliage and fruit. 



The tests of the various lime-sulphur preparations have not yet been suffi- 

 cient to determine their value as a preventive of black rot. Neutral copper 

 acetate in the proportion of 1 lb. to 50 gals, of water has been found the best 

 nonstaining preparation for final applications. 



Coffee diseases of the New World, G. Massee (Roy. Bot. (Jard. Keio, Bui. 

 Misc. Inform., 1909, No. 8, pit. 337-3 U, fio. 1) ■ — A technical description is given 

 of a leaf spot disease of coffee due to Sphcerostilbe flavida. This disease has 

 been known for a number of years and is said to have been reported from 

 several Central and South American countries. 



The leaves, young shoots, and fruits are first attacked, circular whitish 

 patches being produced upon the leaves. I>eaves that are attacked soon become 

 yellow and fall, and in severe cases the tree may become nearly defoliated. On 

 the young shoots the diseased spots are whitish and more or less elongated. 

 The cortex in such i)laces becomes dry and cracks and finally breaks away in 

 small flakes, leaving the browned wood exposed. On the berries the spots are 

 usually whitish and almost circular in outline. 



The fungus spreads rapidly, and it has been found possible to infect young 

 coffee plants by placing ascospores of the SphiBrostilbe stage upon the un- 

 broken surface of the leaves. The fungus is carried over from year to year on 

 diseased shoots and on the fruit, whether hanging or fallen from the tree. All 

 infected shoots should be cut out and, together with the diseased fruit and 

 leaves, collected and burned. 



Notes are also given on a tap-root disease of the coffee tree, duje to nematodes, 

 which is said to be a common disease in the coffee plantations of Sao Paulo. 

 The tap root seems to be the portion attacked by the nematodes, and presents a 

 very characteristic appearance, being swollen and covered with thickened bark 

 soaked with water. The diseased trees are said to be very conspicuous and 

 readily detected, and as a tree once attacked apparently never recovers, it is 

 recommended that all such trees be uprooted and burned. Treating the soil 

 with carbon bisulphid it is thought will also prove an efficient method of con- 

 trolling this disease. 



Notes on the Hemileia disease of coffee and the resistance of certain spe- 

 cies to the fungus, F. C. von Faber (Tropcnpflanzer, 13 {1909), No. 5, pp. 235- 

 238). — An account is given of the leaf spot disease of coffee, due to H. vastatrix, 

 together with estimates showing the amount of loss that it has occasioned. 

 The peculiar susceptibility of Coffra arahica and its varieties to this fungus is 

 pointed out, and a number of species are mentioned as being more or less 

 resistant. 



Mulberry diseases, E. J. Butler {Mem. Dept. Agr. India, Bot. Ser., 2 {1909), 

 No. 8, pp. 18, pis. 4, figs. 2; Indian Agr., 3/, {1909), No. 8, pp. 249^252).— 

 Descriptions are given of twig blight of mulberries {Coryneum mori), mulberry 



