544 EXPERIMENT STATIOX RECORD. 



Eotutiou of crops for several years is recommended. This fungus, it is thought, 

 may not be distinct from S. libcrtiana, which attaclis vegetables, particularly 

 in storage, and was common in 1912. 



European apple tree canker (Nectria galUgena) was found in an orchard of 

 the college. This is supiiosedly the first report of this fungus on apples in 

 Quebec, though it is thought to be common in the province. 



Pea blight (Ascochyta pisi) was noted, but was not troublesome in 1913. 

 fieptoria pisi was common in some plats. These blights are kept under control 

 by seed selection and rotation. 



Millet smut (Ustilago panici-miUacei) was very serious on Panicum tmli- 

 ueeimi. Fornialin treatment of the seed controls the disease. 



Stripe disease of barley (Helminthosporium yrnmineum) , while severe on 

 oats and on Mansury barley, did not attack other barleys. Formalin treatment 

 gave good results. 



Tip burn of potato w'as severe, being favored by the dry weather, decreasing 

 the vitality of the plants. Conservation of moisture and control of insects and 

 fungi by spraying held the disease in check. Tomato blossom end rot was 

 prevalent, owing also to dry weather. 



Raspberry cane blight {Coniothynitm fuckelii) was also prominent during the 

 dry summer weather. No effective measures of control are known, but cutting 

 out and burning diseased canes and cutting old canes as soon as the berries are 

 picked helps to check the spread of the disease. 



[Plant diseases in Eng'land], R. H. Biffen (Jour. Roy. Agr. Sac. England, 

 74 (1913), pp. 374-376).— This is a part of the report of the botanist for 1913 

 and deals very briefly with cases reported or sent in of diseases affecting cul- 

 tivated plants. 



Bacillus amylobacter seemed to attack potato tubers already infected by 

 Phytophthora infestans. One case of black stalk rot, due to B. melanogenes, is 

 noted. It is thought that the disease may be plante<^l with the seed tubers. A 

 case suspected to be Spongospora scabies was thought to be due to gritty soil 

 constituents (as coal ashes), or to the excessive use of kainit. Uromyces betw 

 and Peronospora schachtii are reiwrted on mangolds, also mildew and club 

 root of swedes. Clover sickness is reported as prevalent, and the use of clovers 

 in rotation not oftener than once in six years is recommended. Bunt of wheat, 

 though reported as being spread by traveling thrashing machines, is easily con- 

 trolled by the copper sulphate or the hot water treatment. 



The fruit diseases reported are peach curl, apple canker, leaf scorch, silver 

 leaf, and strawberry spot. Podosphwra Icucotricha, the cause of apple mildew, 

 was found to be in itself parasitized by a species of Cicinnobolus. 



Outbreaks of white rust (Cystojms candidus) on white mustard and of celery 

 spot (Septoria petroselini apii) were reported too late for effective control. 



Other diseases, as larch canker, mildew on peas, asters, etc.. and a spot dis- 

 ease on tobacco were dealt with. 



The downy mildews, E. M. Du Porte (Ann. Rpt. Quebec Soc. Protec. Plants 

 [etc.], 6 (1913-14). pp. 33-38, figs. 3).— This is a brief discussion of some 

 Peronosporacefe affecting economic plants, with a key to the genera. 



The chemical composition of Bordeaux mixture and its soluble copper 

 content, V. Vebmorel and E. Dantony (Compt. Rend. Acad. Sci. [Paris], 159 

 (1914), No. 3, pp. 266-268). — Reporting a study of the conditions leading to the 

 formation of different comi>ounds in Bordeaux mixture and of the question 

 as to whether the alkaline mixture is free from soluble copper, the author 

 states that when concentrated milk of lime is poured vei*y rapidly into a dilute 

 solution of copper sulphate the visible result is the blue color of stable copper 



