846 EXPERIMENT STATION RECORD. 



Troubles of alfalfa in New York, F. C. Stewart, G. T. French, and J. Iv. 

 Wilson {New York State Sta. Bid. 305, pp. 333-416, pis. 12, fig. i).— This 

 bulletin gives an account of the various hindrances to the successful culture 

 of alfalfa in New York, special attention being given to dodder, fungus diseases, 

 and the impurities and adulteration of seed. 



Among the more serious troubles, aside from impure seed and improper soil, 

 are dodder and the leaf spot. Dodder may be prevented to a considerable extent 

 by thoroughly sifting the alfalfa seed before sowing. Apparently the dodder 

 seldom ripens its seed in New York. Moreover, it is found to be a per- 

 ennial and not an annual plant, as generally believed. Where dodder has be- 

 come well established, the infested areas should be cut over and burned and 

 the crowns of the plants cut oft" and destroyed. After this is thoroughly done, 

 the area may be reseeded with clean seed without much probability of reinfesta- 

 tion. 



Among the fungus diseases noted, the leaf spot {Pseudopeziza medicaginis) is 

 the most troublesome and is, in fact, practically the only fungus disease of 

 real importance. The appearance of the fungus, methods of dissemination, 

 etc., are described, and suggestions given for its control. The only practicable 

 method known is mowing the plants, but if close mowing is followed by a period 

 of dry weather the plants suffer severely. When the disease makes its appear- 

 ance shortly before the hay crop is ready to harvest it is advised that the plants 

 be cut early to avoid the loss of leaves, which is sure to follow if cutting is 

 delayed. 



Among other diseases described are wilt (Sclerotinia libertiuna), anthracnose 

 (CoUetotrichum trifolil), root rot and damping off {Rhizoctonia sp. and 

 Pythiitin deliaryanum) , downy mildew {Peronospora trifoUorum), Ascochyta 

 leaf spot {Ascochyta sp.), Stagonospora leaf spot {S. carpatliica{'i)), Cerco- 

 spora leaf spot {C. medicaginis) , Alternaria disease of seed, and frost blisters 

 on alfalfa leaves. Alfalfa is sometimes attacked by nematodes {Ileterodera 

 radicicola) , causing the root knot. A number of diseases of unknown cause are 

 briefly described. 



A bibliography of more than 100 titles concludes the bulletin. 



Alfalfa troubles, F. H. Hall {Neiv York State Sta. Bui. 305, popular ed., 

 pp. 3-16, figs. 2). — This is a popular edition of the above bulletin. 



A new smut on Bromus secalinus, P. Magnus {Hedirigia, ^S {1908), No. 3, 

 pp. 145, 146, fig. 1). — A technical description is given of Tilletia belgrudensis, a 

 parasite of B. secalinus, which the author thinks is specifically different from 

 T. caries. The new species is believed to be widely disseminated in eastern 

 Europe and Asia. 



Dry rot of potato tubers, G. H. Pethybridge and E. H. Bowers {Econ. Proc. 

 Roy. Dublin Soc, 1 {1908), No. 14, pp. 547-558, pi. 1; abs.in Jour. Roy. Hart. Soc. 

 [London], 34 {1908), No. 2, pp. 282, 283).— X description is given of a dry rot 

 of potato tubers. The authors have come to the conclusion that it is due to 

 Fusariuni solani, acting independently of any other organism, and that the 

 fungus is a true pai-asite. Many of the tubers attacked failed to produce 

 plants when used as sets, and others became shriveled to dry hard masses when 

 kept in storage. 



The results of numerous experiments with this fungus are given, and it is 

 recommended as preventive measures that all suspicious-looking tubers should 

 be rejected when the crop is dug and not stored. Stored potatoes should be 

 examined from time to time and all affected tubers removed. Care should be 

 taken to prevent wounding during the lifting and handling of the crop. No 

 wounded tubers should be stored, and storehouses should be disinfected from 

 time to time. 



