1919] DISEASES OF PLANTS. 249 



tliut II spraying of liiue-suliihur and lead ars"nate be applied. This was sent 

 to coninjitteonien who by prearrangenient passed it on until every grower was 

 readied. It is stateil that great savings have been effected by following this 

 plan of organization, which is to be extended. 



Apple blotch, a serious fruit disease, A. 1). Selby (Ohio t^ta. Bui. 333 (lOlU), 

 pp. Jf91-505, p(fs. ,5). — According to the author, the apple blotch due to Fhyllos- 

 ticta solifaria has become a serious menace to apple production in southern 

 Ohio. The characteristics of the disease are described, and it is stated that 

 fruit affected by the blotch is rendered unsightly and is at times distorted and 

 malformed. The juiciness of the fruit is considerably reduced. On the twigs 

 caid^ers are formed, and the fungus is said to live over winter in the cankers on 

 the twigs. The leaves and leaf stalks are also attacked in a characteristic 

 manner. 



A review is given of experimental work that has been reported for the con- 

 trol of this disease, and, based very largely on work done outside of Ohio, the 

 author suggests methods of control. These include proper pruning, spraying, 

 and working over orchards that are planted to specially susceptible varieties 

 of apples. 



The control of crown gall of apples (Iowa ksta. Rpt. 1018, p. 2G). — A brief 

 report is given on two years' experiments in which a number ttf fungicides 

 were tested to determine their value in preventing crown gall of apples. 



In most instances the materials used proved of little value. However, a 

 thick paste composed of copper sulphate and lime into which the grafts were 

 dipped just before planting has given rather promising results. The mixture 

 sticks to the vmion, does not interfere with the healing process, and seems to 

 kill the organisms that come in contact with the young tree. This method 

 of treatment has been tried for two seasons with such satisfactory results 

 that a nursery company treated this year about 500,000 apple trees prepara- 

 tory to setting them out. 



Powdery mildew of the apple, W. J. Allen and W. le G. Breueton (Af/r. 

 Gas. N. (S. Wales, 29 (191S), No. 6, lip. 408^il2). — Noting results of experiments 

 with various fungicides carried out since 1915, the author states that from 

 this work, which is still in progress, it can be concluded that all mildewed 

 terminal buds or affected wood should be removed and burned at the time of 

 winter pruning. Iron sulphid should be applied as a spray first in the pink 

 stage before the petals begin to open, second in connection with the calyx 

 spray (arsenic) for codling moth, third three weeks later with a second 

 arsenic spray, and fourth with a third arsenic spray. 



Apparently this treatment is more effective for the second season, due to 

 the weakening effect of th(> first year's spraying on tlie fungus. 



Control of black raspberry anthracnose and tip blight (Iowa Sia. Rpt. 19 IS, 

 pp. 26, 27). — ^These two diseases are said to be quite prevalent in the State, 

 and experiments for their control were conducted at Council Bluffs. Lime- 

 sulphur and Bordeaux mixture were tested, three applications being given. 

 No tip blight developed during the season, so that the report of the experi- 

 ments applies only to the anthracnose. Both fungicides checked the disease, 

 but llme-sulplnir seemed more efficient than Bordeaux mixture in this respect. 



Development and treatment of grape downy mildew, L. Ravaz (Prog. Agr. 

 et Vit. (Ed. VEst-Centrc). 38 (1917), Nos. J,8, pp. 529-531; 50, pp. .'}77-6Sl : 39 

 (1918), Noft. 2, pp. 25-29; //, pp. 73-76; 6, pp. 121-125, fig. Jf).— The author gives 

 results of studies on grape downy mildew as carried on since 1914 in the School 

 of Agriculture at Montpellier. 



It is stated that the chemical composition and the physical state of copper 

 fungicides depend largely upon the proportions employed and the mode of 



