846 EXPERIMENT STATION BECOKD. 



It is thought probable, however, that soil moisture is a more important factor 

 in attack by stinking smut than is the temperature during the germination of 

 the seed. 



A Phoma disease of western wheat grass, P. J. O'Gaba (Science, n. ser., jffS 

 (1916), No. 1099, pp. 110, 111). — A preliminary account is given of a Phoma dis- 

 ease of Ayropyron smithii, a more extended account of which is promised for 

 a later publication. 



Gummosis, or the gumming of fruit trees. G. P. Daenell-Smith and E. 

 Mackixnon (Agr. (Inz. N. .S'. Walc-f, 26 (1915) . Xo. 5. pp. 405-410).— The authors 

 give a brief historical 'survey, with notes on reports by several investigators, 

 dealing more particularly with that of Butler (E. S. R., 24, p. 74G). 



While various causes and remedies are discussed, the general conclusion is 

 reached that the one great measure, at once remedial and preventive in this 

 connection, is proper attention to drainage. 



[Venturia inaequalis and V. pirina in pure cultures], S. P. NovourpenskiI 

 (Zhvr. liolilzni Rnst.. No. 4-5 (1914), P- 1^0: ahs. in Mat. Mikol. i FHopatoI. 

 Ross., 1 (1915), No. 2, p. 61). — The author briefly states that the apple scab 

 fungxis and the pear scab fungus are readily distinguishable in pure cultures 

 by the color of their mycelium and the character of their growth. He also 

 reports his observations on the development of apple scab in storage, the incu- 

 bation period liolng only five days. 



[Fusicladium pirinum in pure cultures], G. TwriTXi^Kii (Jaczewski) (Mat. 

 Mikol. i Fitopalol. Nous., 1 (1915), No. 2. pp. 57-60, figs. S).— Growth of the pear 

 scab fung\is (F. pirinum) in the author's studies appeared to be normal on 

 gelatin as well as on cooked potato, carrot, and pear, but somewhat retardetl 

 on apple. Involution forms such as were reported by NovouspenskTI (see 

 above) in case of the apple scab fungus were not observed in the cultures of 

 F. pirinum. 



[On the etiology of Stippigkeit]. I. L. SERmxov (Zhur. Bnli7\z)ii Rast., No. 

 SS (1914). p. 51 : ahs. in Mat. Mihnl. i Fitopatol. 7?o.<J.<f., 1 (1915), No. 1, p. 75).— 

 Large losses are said to be sustained every year by Russian apple growers 

 through a physiological fruit spot called in Germany Stippigkeit. Certain exi)©- 

 riments conducted by the author have led him to think that this disease is due 

 to intensive culture. 



[White and brown fruit spot of pear], I. Jj. Serptnov (Zhur. Bo1(?zni Rast., 

 No. 4-5 (1914). p. n.^: ahfi. in Mat. Mikol. i Fitopatol Ross., 1 (1915), No. 2, 

 p. 61). — Two leaf spot fungi commonly appearing on pear leaves, Scptoria piri- 

 cola and Entomosporium maculatum, have been reported by the author ns 

 attacking the fruit also. 



Experiments on American gooseberry mildew in Cambridgeshire, F. T. 

 Brooks, F. R. Petherhridge and G. T. Spinks (Jour. Bd. Agr. [London}, 22 

 (1915), No. 3, pp. 227-230). — The purpose of these experiments, which were 

 made in 1913-14, was to see if some form of spraying or soil treatment carried 

 out on a commercial basis could replace the present system of pruning. In 

 1914 the summer stage of the fungus was particularly prevalent and wide- 

 spread, so that the experiments were carried out under severe conditions. The 

 treatment was probalily more carefully done than would often be the case in 

 commercial enterprises. 



Spraying twice in the early part of the spring with lime sulphur or Bordeaux 

 mixture, while somewhat helpful, was not profitable. Soil treatment and 

 winter spraying also proved to be ineffective. Heavy use of farmyard manure 

 favored the disease by causing abimdant succulent growth. Pruning is deemed 

 the only practical means of checking the dise^ase. This is best carried out in 



