1917] DISEASES OF PLANTS. 543 



by the use of the formaldehyde treatment, which is sliown to be both simple and 

 inexpensive. One pint of formaldeliyde is added to 50 gal. of water, and the 

 seed are thoroughly moistened by constant stirring, spread out to dry, and sown 

 as soon as they will run through the drill, or dried more thoroughly if sowing is to 

 be postponed. 



Leaf smut of timothy, G. A, Osnee {New York Cornell Sta. Bui. SSI (1916), 

 pp. 187-230 pi. 1, figs. 14). — The leaf smut of timothy due to Vstilago strke- 

 fortnis, which also occurs on a large number of other grasses, is described. This 

 fungus is of economic importance through its reduction of the yield of hay and 

 of seed. The symptoms of the disease, its etiology, and pathology are described, 

 after which an account is given of the effect of seed treatment by means of for- 

 jnaldehyde, hot water, and copper sulphate solutions. The results, while not con- 

 clusive, are considered to point strongly to the probability that the disease may 

 be controlled by treating the seed with hot water. 



A bibliography is appended. 



Plant diseases affecting alfalfa, L. E. Melchebs {Quart. Rpt. Kans. Bd. 

 Agr., 35 {1916), No. 138, pp. 339-353, figs. 19).— Brief popular accounts are given 

 of a number of diseases occurring on alfalfa in Kansas, the diseases being grouped 

 according to their causes as parasitic or nonparasitic. In the first group the 

 author describes dodder, leaf rust, leaf spots, bacterial stem blight, violet root 

 rot, downy mildew, and a Phoma stem disease. In the second group accounts are 

 given of a stem-cracking disease and yellow top of alfalfa. 



In addition to the diseases enumerated, brief accounts are given of brown root 

 rot, crown wart, and root knot, parasitic diseases which are not yet known to 

 occur in the State. 



Alfalfa crown wart in the western United States, R. McKee {Jour. Amer. 

 Soc. Agron., 8 {1916), No. 4< PP- 244-246)- — Discussing the life history and dis- 

 tribution of Urophlijctis alfalfw, the author states that the question whether or 

 not this fungus is endemic in the western United States has not yet been settled. 

 Alfalfa plants grown in 1910 from seed imported from Peru, where the disease is 

 known to exist, had considerable crown wart in 1914. Plants, apparently 

 healthy, of Medicago falcata, originating at Highmore, S. Dak., and grown in 

 1914 and 1915 on ground that had never before grown alfalfa, showed a few well- 

 developed galls of the crown wart. In this case it is thought that the farm im- 

 plements may have carried the infection from other plants at the station. 



Observations made in the Sacramento Valley are considered to show that the 

 crown wart decreases the yield of hay and shortens the life of the plants. It 

 occurs on light, sandy, and peat soils almost or quite as abundantly as on 

 heavier soils, but is more abundant on overflowed than on higher lands. In this 

 region the fungus is in its active stage of gi-owth during the latter part of winter, 

 spring, and early summer, the galls drying and disintegrating early in July. The 

 disease is thought to be more abundant and widespread in the western United 

 States than is commonly supposed. 



A new disease of beets in northern France, E. MiioE {Vie Agr. et R^irale, 

 5 {1915), No. 19, p. 341, fig. 1). — A description is given of a beet disease which 

 appeared in 1915 in northern France. It is characterized by orange-colored spots, 

 irregular swellings, and distortion of the foliage. The old leaves are the first to 

 show alteration, which is associated with more or less retardation and abnor- 

 mality of development in other parts of the plant. The trouble is thought to be 

 due to physiological causes. 



Is cucumber mosaic carried by seed? J. A. McOlintock {Science, n. ser., 

 ^4 (1916), No. 1144, pp. 786, 7S7). — The author presents evidence which seems to 

 show that the cucumber mosaic, or white pickle, disease is carried by seed. 



