DISEASES OP PLANTS. 745 



in the center of each spot. The disease has been observed on apples from Iowa, 

 Missouri, Virginia, New Yorlc, Oregon, and Washington. 



The cause of the trouble is not certainly known, but there is a strong sus- 

 picion of injury by arsenate of lead used in spraying. Low temperatures retard 

 or prevent its development, and the trouble may be partly avoided by placing 

 the fruit in cold storage as soon after picking as possible. See also a note by 

 O'Gara on page 759. 



Maine apple diseases, W. J. Morse and C. E. Lewis (Maine Sta. Bui. 185, 

 pp. 337-392, pis. 16). — This is a discussion of the diseases, both parasitic and 

 nonparasitic, to which the apple orchards of Maine are subject, including rather 

 extended descriptions of the symptoms, range, methods of dissemination, and 

 means of combating those which are the most common and dangerous. 



Under the nonparasitic group, the authors describe : Winter, crotch, frost, 

 hail, and spray injuries, leaf spot, Baldwin spot, stag horn, and lichens on the 

 trees. Of the parasitic diseases, the following are discussed : Scab, Cylindro- 

 sporium fruit spot, sooty blotch, and fly speck of the fruit, Sphneropsis leaf 

 spot, powdery mildew, Penicillium or blue mold, and bitter, brown, and pink 

 rots; Alternaria, Botrytis, Phoma, Hypochnus, Fusarium, Verticillium, En- 

 domyces, and Rhizopus decays ; canker and twig blight, and Sphteropsis, bitter 

 rot, Myxosporium, Corj-neum. Phoma, Cytospora. and pear blight cankers, and 

 crown gall and wood-destroying fungi. Under orchard sanitation, sprays, and 

 spraying, the authors enumei'ate the different kinds of sprays to be used, their 

 preparation, and methods of application, including Bordeaux mixture, and 

 self-boiled, home-boiled, and commercial lime-sulphur sprays. 



Spraying' experiments with, a lime-sulphur summer wash, E. S. Salmon 

 (Jou): Bd. Agr. [London], 11 {1911), No. 11, pp. 8S1-S91). — ^The results are re- 

 ported of experiments with different strengths of home-boiled lime-sulphur mix- 

 tures in regard to foliage injury to certain varieties of apples and gooseberries. 

 It was found that late summer spraying with this mixture caused more or less 

 leaf scorching and leaf fall on certain varieties, the amount of injury deiiend- 

 ing upon the strength of the solution used and the variety of apple or goose- 

 berry sprayed. 



Use of self -boiled lime sulphur in combating' scab and brown rot of peach, 

 H. W. Barre (South CaroIhM Sta. Rpt. 1910, pp. 27, 28).— The results are 

 reported of experiments in which 2 applications of self-boiled lime-sulphur 

 mixture (8:8:50) were used on Carmine and Belle of Georgia peaches, and 

 a third on Elberta. The lime-sulphur spray proved very successful in con- 

 trolling the brown rot, but was not quite so efficient with the scab, due, it is 

 thought, to not thoroughly covering the surface of the fruit with the spray 

 mixture. 



Brown rot experiments in 1909, A. C. Lewis (Ga. Bd. Ent. Bui. 32, 1910, pp. 

 35-.'i3, fig. 1). — The results are given of experiments with self-boiled lime- 

 sulphur mixtures with and without arsenate of lead, with concentrated lime 

 sulphur, and with Bordeaux mixture. 



All the solutions used, with the exception of the self-boiled lime-sulphur and 

 arsenate of lead sprays, severely injured the trees. Three applications were 

 made on the lime-sulphur plats. The first consisted of arsenate of lead and 

 lime, 2 : 3 : 50, and the other two were lime-sulphur and arsenate of lead sprays. 

 8 : 8 : 2 : 50. The self-boiled lime-sulphur sprays did not injure the fruit or 

 the foliage and protected the trees against scab, brown rot, and curculio, 

 while the sprayed fruit had a better color and kept better in storage and in 

 shipping. 



On the means for combating plant diseases, K. MtJLLER (Ber. Grossh. Bad. 

 Landiv. Vers. Amt. Atignstenb., 1909, pp. 108-115). — Experiments made during 



