650 EXPERIMENT STATION RECORD. 



On the treatment of mildew, J. Gagnaiee (Rev. Vit., 35 {1911), No. 891, pp. 

 ^g^ jfQ)_ — The author briefly discusses tlie ravages of mildew in France during 

 1910, and concludes from this year's experience that preventive treatments 

 should be many, and of considerable strength, consisting of alternate applica- 

 tions of liquid and powdered mixtures of copper salts, especially during the 

 period of inflorescence and when the seed in the young grapes are hardening. 



The physical properties of the grape and resistance to the mildew, 

 J. Laurent (Compt. Rend. Acad. Set. [Paris], 152 (1911), No. 2, pp. 103-106).— 

 The author claims that the resistance to the mildew increases with the molec- 

 ular concentration of the sap of the vine, as in a series of experiments it was 

 found that the varieties known to be more or less resistant showed a higher 

 degree of molecular concentration than vines susceptible to the disease. Tests 

 with the potato gave similar results as to resistance against the late blight of 

 the potato. 



A new disease of the mulberi-y, F. Bubak (Ber. Dcut. Bot. GesclL, 2S 

 (1910), No. 10, pp. 533-537, pi. 1). — The author describes as new a fungus, 

 Tlujrococcum sirakoffii, which forms under the bark of the small branches and 

 twigs of the mulberry (Morns alba) black stromatic tubercles which later 

 break through the bark and form irregular black patches on the surface. The 

 mycelium invades both the bark and the bast regions, resulting ultimately 

 in the death of the twigs and of the seedlings which are attacked. 



The diseases of the orang'e, G. Gandara (J/ew. y Rev. Soc. Cient. "Antonio 

 Alzate," 28 (1910), No. 5-8, pp. i 55-^92). —Previously noted from another 

 source (E. S. R., 24, p. 157). 



Treatment of gum disease, A. F. Call (Proc. Fruit Growers^ Conv. Gal., 

 37 (1910), pp. 66-71). — In an address before the thirty-seventh Fruit Growers' 

 Convention of California the author discusses the probable causes of gummosis 

 In lemon and orange trees, and gives the remedies that he and other citrus 

 growers have found ethcient in controlling this disease. 



It is claimed that gummosis of the lemon was most common on land im- 

 perfectly drained, and on trees around which the sediment had collected. 

 From observations and experiments the author concludes that the formation 

 of gum is due to a deadening of the member, destroying its sap-carrying 

 power and thereby stopping the down-flowing sap, which then collects in 

 pockets under the bark. These pockets of sap remain until they are evaporated, 

 thus forming a gum which later rots the bark. It is claimed that lemon trees 

 can be cured of this disease by cutting drainage fuiTOWS for the sap on the 

 trunks about 2 in. apart extending to the limbs, oiling the bark 2 or 3 times 

 at intervals of 2 weeks with some soft animal oil, such as neat's-foot oil, 

 whitewashing the trees, removing the earth and sediment from the foot of 

 the trees, thereby exposing the crown roots to the air, and preventing water 

 from standing around the trees. 



The author also claims that by following the remedies recommended for 

 lemons he was able to cure orange trees of gummosis or scaly bark of the 

 orange. 



Diseases of the areca palm (Areca catechu). — I, Koleroga or rot-disease, 

 L. C. Coleman (Ann. Mycoh, 8 (1910), No. 6, pp. 591-626, pis. 3, figs. 4; Dept. 

 Agr. Mysore, Mycoh 8er. Bill. 2, 1910, pp. VI+92, pis. 16, figs. 6, maps. 2).— 

 The author gives the distribution of the disease, the results of infection experi- 

 ments, morphology of the fungus, and methods used for combating it. The 

 disease is limited to the rainy season, which is about 3J months, and is found 

 in Mysore, North and South Canara, Malabar, and Cochin. 



It usually attacks only immature nuts, producing a rot which causes them to 

 drop off soon after the attack, but it occasionally destroys the tops of the trees. 



