DISEASES OF PLANTS. 345 



Tasmania. The shrinkage tests on blue gum showed an average shrinlcage in 

 vohmie of 21.8 per cent when dried from a green to an oven-dry condition as 

 compared with an average of about 18 per cent for eastern red oali. Seasoning 

 experiments basett partly upon Australian practice are being conducted to 

 determine the best methods of handling California grown eucalypts. 



What are the causes of the serious failure of natural regeneration of old 

 spruce stands on high situations and how can this unfavorable condition be 

 overcome? How are su.ch. stands to be treated in the future? B. Bavieb 

 (Sclmeiz. Ztschr. ForsHc, 61 (1910), Nos. 5, pp. U5-152; 6-7, pp. 195-201; 8, 

 pp. 227-236). — In this thesis the author aims to answer the above questions. 



How to grow black walnuts, C. A. Scott (Kansas Sta. Circ. 13, jjp. 3). — 

 This circular contains brief suggestions relative to preparing the seed for plant- 

 ing, where and how to plant, and the cultivation and care of black walnut. 



DISEASES OF PLANTS. 



Diseases of economic plants, F. L. Stevens and J. G. Hall (New York, 1910, 

 pp. X+513, figs. 219). — This work treats primarily of the diseases of economic 

 plants which are due to attacks of fungi, bacteria, slime molds, etc., although 

 some attention is given to those troubles generally attributed to physiological 

 disturbances due to environmental or other causes. The book is designed for 

 those who wish to recognize and treat plant diseases without an extended 

 investigation as to their causes, and the information is largely drawn from the 

 authors' experience, supplemented by the published results of investigations at 

 the various agricultural experiment stations and this Department. 



The characters used in describing diseases are the more obvious ones, such 

 as appear to the eye with or without a hand lens, and technical discussions are 

 eliminated as far as possible. After describing the disease the best methods 

 of combating it are given. The diseases are grouped according to crops, and 

 chapters are given on fungicides, spraying, soil disinfection, plant sanitation, etc. 



Plant diseases, M. Hoffmann (Jahresber. Landw., 2If (1909), pp. 203-210). — 

 Brief abstracts are given of several of the more important papers on fungus 

 diseases of economic plants issued in Germany, mainly during 1909, including 

 articles on rusts and smuts of cereals and their control (B. S. R., 21, p. 44G; 

 22, p. 745; 23, p. 46), the heart or dry rot of sugar beets (E. S. R., 21, p. 446), 

 and the leaf-roll disease of the potato (E. S. R., 21, p. 243). 



Report on plant diseases, E. Jordi (Jahrcsher. Landw. Scliule Ri'ittl, 1909-10, 

 pp. 108-llJt). — Tabulated statements are given of reports from various sections 

 on the prevalence of grain smuts and the use of seed soaking as a remedy, on 

 the leaf roll and blackleg of potatoes and the most susceptible varieties, and 

 on the general appearance and yield of cherries and other stone fruits. 



In experiments conducted by the station on the control of stinking smut of 

 wheat and rye it was found that soaking the seed in a 0.2 per cent solution of 

 formalin gave the best results with both crops, while a 0.1 per cent solution of 

 formalin and a 0.5 per cent solution of copper sulphate was less favorable. 

 The germination of the rye was not more injured by the soaking than the wheat. 



Comparisons of the yields of certain varieties of cereals from rusted plants 

 and from healthy plants showed that the rusted plants gave from to to ^ less 

 yield in grain. The breeding and cultivation of rust-resistant varieties is there- 

 fore recommended. 



Mycological review for the year 1909, G. Beiosi (Bol. Min. Agr., Indus, c 

 Coin. [Rome], 9 (1910), 8er. C, No. 5, pp. 79-88). — After discussing the common 

 diseases of the clovers and vetches, a list of plant diseases examined and iden- 

 tified during the year at the botanical station at Pavia is given. 



