566 EXPEEIMENT STATION RECORD. 



with the different fungi showed that those occurring upon the barley would affect that 

 host only, and not oats, rye, or wheat. The other species {H. avenai), while most 

 abundant upon oats, gave a few infections on barley, but none upon the other cereals. 

 The time of seeding and temperature, during the first few days of germination, were 

 found to have an important bearing upon the amount of disease; plants seeded in 

 the cool months of spring or autumn were much more affected than those seeded 

 when the average temperature was higher, July and August seedlings being almost 

 wholly without disease. Differences in susceptibility of varieties are noted, and it 

 is claimed that soaking the seed in hot water or in a solution of potassium sulphid 

 prior to sowing will greatly reduce the disease. 



The gro-wth. of ergot on rye and various grasses, Noffray {Mem. Soc. Nat. 

 Agr. France, 139 {1900), pp. 501-555). — From experiments conducted by the author 

 it is claimed that in the germination of the ergot the sclerotia must not be more 

 than 1 year old and the climatic conditions must be mild and humid. The occasional 

 almost total disappearance of ergot from crops is explained by the unfavorable 

 atmospheric conditions which prevailed at the time of the germination of the fungus. 

 In addition to the rye, the author enumerates 30 species of grass which are subject 

 to attacks of ergot, among them are the dog-tooth grass, couch grass, meadow fox- 

 tail, various species of brome grasses, timothy, fescue grasses, rye grass, orchard 

 grass, and several species of Poa. For the eradication of ergot the author recom- 

 mends careful screening of all seeds, and care to avoid distributing the infected 

 material from one field to another by means of hay or stock. In case of pastures 

 which have become seriously infected, it is recommended that some cultivated crop 

 should be employed for a few years until the danger from propagation has jJassed. 



Potato diseases and their remedies, L. R. Jones ( Vermont Sta. Rpt. 1900, pp. 

 268-281, fig. 1). — In the season covered by this report the atmospheric conditions 

 were, on the whole, favorable to the potato crop. The yields were somewhat 

 reduced by dry weather, but on this account there was less disease than usual. 

 Experiments were conducted to test the comparative value of several fungicides and 

 insecticides when applied to potatoes. Standard Bordeaux mixture to which Paris 

 green w-as added, Bug Death, Laurel green, and gypsum and Paris green were 

 applied under similar conditions. At the time of the first application and for nearly 



2 weeks thereafter but little difference could be distinguished in the condition of 

 the several plats. By the time of the second application marked differences began 

 to show themselves, which increased as the season advanced. In all cases the 

 plants receiving the Bordeaux-Paris-green mixture were more flourishing and the 

 leaves larger and of darker green color. The effect of the different fungicides, as 

 shown by the yield of the various plats, is given in tabular form. The results are 

 especially significant since there was no fungus whatever on any of the potatoes. 

 Bordeaux mixture was again shown to be a valualjle remedy against insect attacks. 

 The amount of gain due to the use of this mixture when applied to experimental 

 plats was almost exactly duplicated upon the main field of the farm, the sprayed 

 plants yielding 223 bu. per acre as compared with 150 bu. from unsprayed rows. 



The number and dates of applications to secure the best results were investigated, 



3 applications being made of the Bordeaux-Paris-green mixture on July 26, August 

 17, and September 8. The yields of potatoes sprayed at different times showed that 

 the first application was the most important one, and that about one-half the entire 

 gain was attributed to that. The second and third applications were about equal in 

 importance, each of which added about 25 bu. per acre to the entire crop. 



Experiments are reported on the prevention of potato scab, in which comparative 

 trials were made of corrosive sublimate, formalin, formaldehyde gas, sulphur, sulphur 

 fumes, and insolation. Where the soil was free from the scab germs and scabby 

 seed was used, a scabby crop resulted, but where the soil was clean and the seed 

 properly disinfected a clean crop was secured. Where the soil was badly infected 



