1084 EXPERIMENT STATION EECORD. 



different varieties to disease is shown and the influence of soils, meteorological con- 

 ditions, fertilizers, seeding, etc., on rust development are discussed. The role of bar- 

 berry and boraginaceous and other plants on the alternate generations of the rust 

 fungus is commented upon at considerable length. The losses due to cereal rusts are 

 discussed and suggestions given for their prevention. Among the suggestions offered 

 are the sowing of resistant varieties, early seeding, and rational fertilizing. 



The treatment of stinking- smut in wheat, J. Reed {Colorado Sta. Bid. 79. 

 pp. S). — A description is given of the stinking smut of wheat caused by Tdldia fniens, 

 and 2 methods of treating the seed for smut prevention are described. In these 

 treatments the seed was either soaked or sprinkled with solutions of copper sul- 

 phate, corrosive su1)limate, potassium sulphid, and formalin. The results oT)tained 

 showed the efRcien(;y of copper sulphate, corrosive sublimate, and formalin, and 

 demonstrated that potassium sulphid, besides being very expensive, isnotan ethcient 

 remedy. Sprinkling the solutions over the grain and thoroughly mixing by raking 

 or shoveling is recommended as the quickest and easiest, as well as most efficient 

 treatment. 



Potato diseases and their remedies, L. R. Jones and W. J. Morse ( Vermont 

 Sta. lipt. 1002, pp. 209-230). — A report is given of the potato diseases as they occurred 

 in 1901 and 1902, the results of spraying experimenis, the relation of date of digging 

 to development of potato rot, the effect of top pruning potatoes, and potato scab 

 experiments. During 1901 and 1902 then; was an unusual prevalence of the late 

 blight and rot due to Ph/tojditJiora i»festfm.'<, and the conditions are believed favorable 

 for the destructive occurrence of the disease in 1903 unless the summer should be an 

 unusuall}^ dry one. In order to prevent serious losses from this cause the authors 

 suggest the selection and saving of seed from the earlier planted crop on light soils 

 so that there will be as little fungus as possible introduced to the seed potatoes, and 

 the thorough spraying of the plants with Bordeaux mixture during the season. 



The spraying experiments reported were begun in 1901, comparison being made 

 between Bug Death and a Bordeaux-Paris-green mixture. The results are given at 

 some length, from which it ai)pears that although Bug Death was used in very large 

 amoimts its ineflicieney as a fungicide was demonstrated. During the second year 

 the spraying exi^eriments were continued but Bordeaux mixture and Paris green 

 alone were used. The results of these experiments are shown and a tabular state- 

 ment is given showing the average gain for 12 years attributed to the use of Bordeaux 

 mixture on late potatoes. The average increased yield attributed to this cause was 

 .115 bu. per acre. 



While carrying on the spraying experiments during the summer the soil of certain 

 rows was sprayed to ascertain whether this treatment would prevent the development 

 of the spores falling upon the soil and reaching the tubers. The results ol)tained 

 are not considered conclusive, and although there was some evidence of eradication 

 of disease this method of spraying is not recommended as practicable. 



The question of how soon blighted potatoes should be dug has been frequently 

 asked the authors, and a series of investigations was undertaken to ascertain the 

 proper time of digging. The size of the plats and the extent of the experiment are 

 considered too limited to admit of generalizations, but it appears that there was 

 usually a greater loss from the earlier digging. So far as the investigations go, they 

 seem to show that where there is danger of potato rot it is best to delay the digging 

 for 10 days or more after the tops have died. 



The effect of top pruning was studied on account of the unusual luxuriance of the 

 potato tops, especially where they had been properly sprayed. The common belief 

 was expressed that such a growth would interfere with the jiroduction of tubers, con- 

 sequently the stalks of alternate rows were clipped back so as to present only about 

 a foot of growth above the soil. The yield from the different rows at harvest is 

 shown, from which it appears that practically ^ of the crop was sacrificed by the 

 cutting of the tops. 



