IRISH GARDENING 



VOLUME VI. 



\o. 63 



A MONTHLY JOURNAL DEVOTED TO THE 



ADVANCEMENT OF HORTICULTURE AND 



ARBORICULTURE IN IRELAND 



MAY 



IQII 



Black Stalk-Rot 



By Paul A. Murphv. 



A DISEASE of potatoe; 

 g-ated in Ireland is 

 considerable interest 

 ag-riculturists g-enerally. It 

 to any particular part 

 of the country, but 

 it is at present, per- 

 haps, rather more 

 prevalent in the West 

 than elsewhere, 

 where it has existed 

 probably for many 

 years, although its 

 identity has been 

 hidden in the com- 

 prehensive n aim e s 

 of " Haug"hing-" and 

 "Yellow Blight." 

 Diseases, which for 

 all practical purposes 

 may be considered 

 identical with ours, 

 have been described 

 in Germany, France, 

 Holland, Canada, 

 the U. S. A., and 

 possibly in other 

 places ; so that the 

 pest is widespread, 

 and is not, as might 

 be supposed, peculiar 

 to Ireland. In (ier- 

 many it is estimated 

 that 10 to 15 per cent, 

 on the average, and 

 at times even 75 per 

 cent., of the potato 

 crop is destroyed by 

 this or a very similar 

 disease. So far as 

 I am aware no such 



; recently investi- 



likely to prove of 



to gardeners and 



is not confined 



A SuNGLK Akkected Stalk of Potato 



Showing the abnormal foliage and decay at its base 



severe attack as the latter has yet been ex- 

 perienced in Ireland, but the possibility of 

 such a calamity should be sufficient to put 

 growers on the alert. 



Black stalk-rot is 

 usually the earliest of 

 the potato diseases 

 to manifest itself, 

 infected plants being 

 found as early as the 

 middle of June. Dur- 

 ing the following 

 month or six weeks 

 the attack is at its 

 height, but once 

 August sets in it 

 declines very rapidly. 

 This fact is of import- 

 ance, because at dig- 

 ging time the plants 

 which have died of the 

 disease leave no trace 

 behind them but their 

 entirely rotted, or 

 even more dangerous 

 slightly infected, 

 tubers. As will be 

 shown later, one of 

 the ways, at least, in 

 which the disease 

 lives over the winter 

 is in these slightly 

 attacked tubers. 

 Attacked plants may 

 readily be distin- 

 guished in the field by 

 their light-green or 

 y e 1 1 o w i s h - b r o w n 

 foliage, by their 

 stunted appearance, 

 and by the fact that 



