DISEASES OF PLANTS. 53 



(K-ciirs in Natal luultT alino^t all conditions of 8oil, and in many fasen it may be 

 attri))nted to ])ad drainage, although in pome instances a lack of drainage will not 

 ex})lain the occurrence of the disease. 



The peach; its diseases and suggested remedies, W. A. BofciiER {Nen: Zealand 

 Dcpt. A(jr. Rpt. 1903, pp. 450-460, pi. 1). — The peach is said to be almost entirely free 

 from insect pests in New Zealand, but is subject to considerable injury from a number 

 of fungus diseases. Among the diseases described are peach curl, shot-hole fungus, 

 peach rust, and attacks of Cla.^terosporitnn amygdaleannii. This last fungus attacks 

 both the bark and leaf, resulting in the defoliation of trees and their subsequent 

 weakness. The author recommends early and persistent spraying with Bordeaux 

 mixture composed of 10 lbs. of copper suljihate, 10 lbs. of lime, and 40 gal. of water. 



Peach-leaf curl, G. E. Stone {Mta<mrhiii<t'Ui< State Bd. Agr. Nature Leaflet 13, j^p- 

 4, fiO^- ~) • — -^ description is given of the peach-leaf curl, due to E.voascus deformans, 

 and spraying with Bordeaux mixture is reconnnended as an efficient means for its 

 prevention. This fungus is said to annually cause a loss to the peach industry of the 

 United States amounting to from two and a half to three million dollars. 



Quince rust, G. E. Stone (Massachusetts State Bd. Agr. Xatnre Leaflet 11, pp. 3, 

 figs. 2) . — Brief illustrated notes are given on the quince rust caused by Gymnosj>oran- 

 gium sj)p. , for the prevention of which the author recommends thorough and repeated 

 spraying with I^ordeanx mixture. 



The witches' broom disease of cacao [Agr. Xeirx [Barbados'], ..-' {1903), Xo. 26, 

 p. '117, fig. 1). — An illustrated description is given of the witches' broom disease of 

 cacao which was first noticed in Surinam in 1898. This disease greatly damages the 

 trees and is accompanied by a hardening of the cacao pods to such an extent that 

 their production is seriously diminished. In the absence of more definite knowledge 

 of the fungus the only remedy to be suggested is the cutting out of the tufted 

 brandies and burning them as soon as observed. 



The alternate form of .fficidium hihisciatum, W. A. Kellerman {Jour. Mycol., 

 9 {1903), Xo. 66, pp. 109, 110). — The occurrence of the jccidium of this rust in great 

 abundance on plants of Hih'n-rns moschentos led the author to search for its teleuto- 

 sporic form. A number of plants were investigated whit-h grew in the immediate 

 vicinity and finally by means of cultures and inoculations the author discovered that 

 the Puccinia form was Purcin ia m uhlenhergipc, a common rust on Muhlenhergia mexicana. 



A rust of the cultivated snapdragon, W. C. Blasdale {Jour. Mycol., 9 {1903), 

 No. 66, 2}p. SI, 82). — In 1895 the author reported the presence of the uredo stage of a 

 rust on cultivated forms of snapdragon. Later the teleuto stages were produced and 

 the fungus was determined to be a new one and named by Holway and Dietel 

 Puccinia antirrhini. Since that time the fungus has appeared every season when 

 attempts were made to grow this plant, completely destroying all plants before they 

 reached the flowering stage. There appears to be no record of the occurrence of 

 similar disease in other ]iarts of the country, and the author suggests that on account 

 of its destructive character it would be well to guard against introducing it into other 

 regions. 



Grape mildew and the use of sulphur, L. DEGRur.Lv {Prog. Agr. et Vit. {Ed. 

 VEst), 24 {1903) , Xo. 14, pp. 417, 418) . — Attention is called to the fact that for some 

 years complaint has been made by certain viticulturists that the use of suljihur does 

 not prevent tlie attacks of the powdery mildew of the grape. A number of these 

 c-omplaints were analyzed and the author concludes that the failure to jirevent the 

 development of the fungus Avas due in part at least to an insufficient use of sulphur. 

 For the thorough protection of the grapevines at least 3 treatments should be given 

 them in which either 130 kg. per hectare of triturated sulphur or 90 kg. of sublimated 

 sulphur should be used. These figures are given as the maxima, which it is not 

 always necessary to attain, but they should be fairly well approximated. 



