DISEASES OF PLANTS. 649 



England, flax wilt (Fusarium lini) and flax rust {Melampsora lini), recom- 

 mending for the former continual rotation of crops. 



Eeport of the professor of botany, J. E. IIowitt (Ann. Rpt. Ontano Agr, 

 Col. and Expt. Farm, S8 {1912), pp. 2.9-55).— The author Investigated a number 

 uf ginseng gardens and found that the most serious diseases in Ontario are 

 the Alternaria blight {A. panax), rust, fiber rot or end rot (Thlelavia hasicola), 

 and a soft rot due to bacteria. These diseases are briefly discussed and, so far 

 as definitely known, methods of prevention are indicated. 



A method of treatment for mushroom root rot, 11. P. Bakss {Oreg. Country- 

 man, 6 (1918), No. S, pp. 118-115, figs. 2). — Among the remedies recommended 

 for this disease of fruit trees, due to ArmiUaria mellca, are the removal of all 

 affected or dead roots and bark, disinfection with Bordeaux mixture, lime sul- 

 phur, corrosive sublimate solution, etc. After surgical treatment exposed sur- 

 faces should be protected with tree paint or grafting wax. 



Fusarium leaf roll of potatoes, W, Himmelijauti {Umschau, 11 (lOlS), No. 

 60, pp. 1046, 1047, figs. 7). — This is a somewhat popular and partly graphical 

 presentation of data, most of which have been noted previously (E. S. R,, 28, 

 p 848). 



Potato wilt, leaf roll, and related diseases, W. A. Orton ( U. 8. Dcpt. Agr. 

 Bui. 64 {1914), PP- 4S, pis. 16). — On account of the confusion which exists among 

 plant pathologists and others concerning a number of potato diseases com- 

 monly referred to as wilt, leaf roll, leaf curl, Fusarium blight, bacterial ring 

 disease, etc., the author has undertaken to bring together the information 

 relating to these diseases in order that they may be more readily differentiated. 



The principal diseases discussed in this bulletin are the Fusarium wilt, due 

 to F. oxysporum, which is said to be widespread in America, but not yet recog- 

 nized from Europe; the Verticillium wilt, caused by V. alboatrum, present both 

 in America and in Europe ; the leaf roll, which Is considered an inheritable 

 disease but probably not due to a parasite and which is common In Europe and 

 has lately appeared in America; the curly dwarf, an inheritable, nonparasitic 

 disease, found both In Europe and in America ; the rosette, due to the fungus 

 Rhizoctonia, which is very prevalent in the western United States ; and the 

 mosaic, which is a pathological condition present both In Europe and in America. 

 These different diseases are described at some length and suggestions given for 

 their recognition, and where known control measures are described. A bibliog- 

 raphy is appended. 



Influence of temperature on the spread of potato diseases, F. Gaul {Dent, 

 handle. Presse, 40 {1913), No. 92, p. 1094). — Referring to observations previously 

 reported by Voges (E. S. R., 30, p. 541), the author states his belief that the 

 drop in temperature from 14.5 to 10.3° C. about August 27, 1912, was largely 

 instrumental in checking the progre&s of Phytophthora and in giving a fair crop 

 of sound tubers notwithstanding the wet weather prevalent about that time. 



Diseases and pests of the sugar beet in Bohemia and of the crops used in 

 rotation, 1911, H. Uzel {Ztschr. Zuckcrindus. Buhmen, 38 {1913), No. S, pp. 

 133-140, figs. 2). — A brief account is given of observations made at the phyto- 

 pathological section of the experiment station for the sugar industry at Prague 

 for 1911, including notes on heart rot, dry rot, red rot due to Rhizoctonia 

 violacea, etc., and a formation of teratological character affecting beets; also 

 on Puccinia glumarum and Urocystis occulta on rye, nematodes attacking oats, 

 and other animal pests on various crops employed in rotation. 



Red rot of sug'ar cane, E. J. Butler and A. Hafiz {Mem. Dept. Agr. India, 

 Bot. 8er., 6 {1913), No. 5, pp. 151-17S, pi. i).— This is in pursuance of previous 

 reports by Butler (E. S. R., 18, p. 450; 19, p. 162) on red rot of sugar cane In 



