1907.] American Gooseberry Mildew. 



45i 



the others about a quarter of a mile. Thirteen of these were 

 found to be affected during the winter, while the disease 

 was discovered in the remaining eight during the summer. 

 The original source of disease was not, however, traced. In 

 the Pershore district six outbreaks were detected, three of 

 which at Pinvin practically adjoin each other; while two more 

 were found about half a mile away. In one of the two latter 

 cases only was the mildew found in the winter ; the other 

 plantation, which was carefully examined without disease 

 being found, became affected in the summer. Between 

 Pershore and Evesham eight outbreaks have been reported, 

 including cases found during the summer, four of which lay 

 close together, while four were somewhat widely separated. 

 Beyond Evesham four more cases were found, the plantations 

 being in these instances also more or less isolated. Of the 

 remaining cases one occurred in the extreme south of the 

 county, one close to Worcester and another about seven miles 

 to the north of that city. The area is wide, but the disease is 

 scarcely found outside it ; while though by no means every inch 

 in each plantation is affected, there are few gardens that have 

 not a certain number of diseased plants. This, then, appears to 

 be a characteristic of the progress of the infection, and the 

 experience of Worcestershire agrees with the experience of 

 Ireland, Sweden and Germany.* 



Situation and Soil. — It has been asserted confidently 

 that the mildew flourishes only on bushes growing in damp 

 and low-lying situations. f This is undoubtedly the case 

 with several of the outbreaks, notably in one place near 

 Evesham, where the plantation slopes down to a small stream. 

 In two plantations at Pinvin (Pershore) adjoining each other, 

 the disease was noticeable only on the lowest parts of the 

 ground which lie low, and are rather damp from the drainage 



* The following sentence, taken from Herr Wilhelm Herter's article ,on the 

 "American Gooseberry Mildew " in the Centralblatt filr Bakteriologie, Parasiten- 

 kunde tmd Infektionskrankheiten, Zweite Abt., Bd. xvii. , No. 22-24, should perhaps 

 scarcely be taken literally : — " Plotzlich an einem Orte erscheinend, erobert sich der 

 Schadling planmassig von diesem Punkte aus das neue Gebiet, von Jahr zu Jahr 

 schneller und verheerender urn sich greifend und alles vernichtend, was ihm in den 

 Weg kommt." The disease has certainly not appeared in so serious a form in 

 England as yet. 



t This appears to be the case in Germany. Herr Wilhelm Herter says {loc. cit) : 

 "In trockenen und erhoht gelegenen Garten fand ich Sphcerotheca fast nie." 



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