850 EXPERIMENT STATION RECORD. 



cinia primi-spinosw, C. persicce, Sphwrotheca pannosa, and Monilia fructigena. 

 Varieties of peaches found resistant are named in connection with each of the 

 first three fungi above listed. 



A contribution to the study of olive rot, G. de Michele (Bol. Arbor. Ital., 

 7 (1911), No. 3-'f, pp. 179-192, figs. 7).— This disease is said to affect old olive 

 trees of diminished vitality, or young trees in consequence of injuries of 

 improper culture. These conditions favor the activity of bacteria which pro- 

 duce changes in the living tissue followed by gradual death of the tree, the 

 details of the process not yet being beyond dispute. 



Incipient appearances are said to be subdued by cutting out cleanly the 

 affected parts and thoroughly disinfecting the wounds. For more advanced 

 stages a similar but more radical treatment is prescribed. Remedial measures 

 looking to the preservation of vigor in tlie trees are also recommended. 



Eruptive disease, or " exanthema," of orange trees in Australia, C. C. 

 Bbittlebank (Jour. Dept. Agr. Victoria, 10 (1912), No. 7, pp. JfOl-'fO//, figs. 

 2). — The author briefly describes this disease, which is claimed to be physio- 

 logical and to be due primarily to wealiened vitality. This weakening is 

 attributed generally to porous, deep, coarse, sandy soil, lacking in organic 

 matter, drying out quickly after rain; to continued drought followed by heavy 

 rain ; and to the presence of large amounts of nitrogenous manures. 



Remedial measures suggested include the plowing in of green crops previously 

 manured with superphosphates, and avoidance of nitrogenous manures. 



Permanganate of potash in viticulture, C. Tbuchot {Prog. Agr. et Vit. 

 {Ed. I'Est-Centre), 33 {1912), No. 34, PP. 229-231).— TYie author recommends 

 as a remedy for a gray rot of grapes, ascribed to Botrytis cinerea, a mixture of 

 15 parts of permanganate of potash with 85 parts of sifted lime, applied in 

 powdered form, preferably after rain or a heavy dew. In a second formula, 

 5 per cent of alum replaces an equal proportion of the permanganate. The 

 action is claimed to be certain. 



Grape chlorosis and its treatment with sodium nitrate and iron sulphate, 

 E. Chancrin {Jour. Agr. Prat., n. ser., 23 {1912), Nos. 22, pp. 683-686; 23, pp. 

 715, 716). — Chlorosis of grai)e leaves is here held to be due in general to poor 

 nutrition, most commonly with lime as a primary injurious factor assisted by 

 various secondary conditions. 



Experiments were conducted under direction of the author in treating seri- 

 ously affected vines with solutions of sulphate of iron and nitrate of soda. The 

 iron salt did not give very good results. The treatment with nitrate of soda 

 in most instances showed considerable improvement, and in many cases complete' 

 recovery, where the dose amounted to 25 or 30 gm. per stock. 



The subsequent influence of fungicides on the vigor and production of 

 grapevines, and their resistance to chlorosis, J. L. Vidal {Rev. Vit., 37 

 {1912), No. 965, pp. 813-818, figs. 2; ahs. in Internat. Inst. Agr. [Rome], Bui. 

 Bur. Agr. Intel, and Plant Diseases, 3 {1912), No. 8, pp. 1887, 1888).— The 

 experiments reported are said to indicate that mildew exercises a more or less 

 remote influence on grapevines, as shown by the reduction of resistance to 

 chlorosis, weakening of vegetation, and lowering of productivity, these influ- 

 ences being somewhat proportional to the damage inflicted at any given time 

 by the fungus, early invasions usually resulting in greater subsequent damage 

 to the vines. 



The author concludes that protection by spraying should extend not only to 

 present crops but to vines with a view to future returns, even light attacks of 

 mildew being carefully guarded against for the sake of greater vigor in the 

 vines. 



