YELLOW-STRIPE IN DAFFODILS. 



163 



disease I have experienced, several articles on the subject appeared in 

 " The Garden," and Mr. Goodwin noted the occurrence of the disease in 

 a bulb of ' Blackwell,' and said he had attributed it to want of change in 

 the soil, whilst a botanist friend had reported that it was believed to be 

 caused by Bacterium hyacinthi, a disease of hyacinths which is well known 

 in Holland and attacks the bulbs in a resting condition. (" The Garden," 

 April 1906, p. 198). 



Later in the same publication (p. 229) Miss Currey suggested that the 

 cause was to be sought in over-division of the bulbs, a suggestion which 

 is supported by Mr. Watts (p. 271). But on the same page, Mr. Jacob 

 says he has found ' Sir Watkin,' ' Princess Ida,' and ' Grand Duchess ' among 

 the worst offenders, and he arrives at the conclusion that if it be a disease 

 it is not an infectious one. He does not think it is caused by the division of 

 the bulbs, and suggests cold as a possible cause. Mr. Peter Barr (p. 303) 

 notices yellow-stripe as a characteristic of 'M. J. Berkeley,' and puts 

 it down to some inherent weakness, but considers the bulbs, though 

 affected, do better in the grass. In 1907 (p. 75), " K.," from North Devon, 

 mentions an outbreak in a row of ' Sir Watkin ' which he can attribute 

 neither to cold, nor to over-dividing, nor to infected soil, " but if to anything 

 besides constitutional liability, then to heat." He thinks the disease may 

 arise from growing large quantities of bulbs with no other vegetation 

 distributed among them, and advocates planting alternate rows of other 

 plants among the daffodils. On the other hand, Mr. Rollo Meyer, 

 of Ampthill (p. 234), has daffodils planted in rows, in the grass, and in 

 clumps between perennials, and finds instances of yellow-stripe among 

 the plants in all three positions. On p. 402 reference is made to an 

 opinion expressed at a meeting of the Scientific Committee of the E.H.S. 

 that the disease came from over-manuring, and a statement by Mr. 

 Bennett-Poe and Mr. Douglas that if plants affected were cultivated in 

 unmanured soil they would recover. Mr. Leonard Buckland (Australia), 

 p. 414, regards "continual change of soil, maiden loam if possible," as a 

 remedy for the disease. 



Mr. A. M. Kir by (" Daffodils," 1907, p. 22), writing of America, seems, 

 like the E.H.S. Committee, to attribute yellow-stripe to the presence of 

 manure. He says : " Year after year, until I learned to be more strict, I 

 used to see here and there a sickly yellowish-leaved stunted daffodil plant. 

 An examination of the soil almost invariably disclosed a lump of manure 

 either in contact with the bulb or where its roots should have been — 

 probably had been, but were destroyed by contact with raw manure" ; 

 and I gather (p. 35) that he found the spring of 1906 specially bad for 

 yellow-stripe, but is inclined to put down the trouble to a covering of 

 manure he had used. 



With reference to the suggestion that manure, or at least rank 

 manure, may be the cause of the trouble, it is, I think, desirable to dis- 

 tinguish the true yellow-stripe from an injury undoubtedly caused by 

 manure in which the whole leaf of the daffodil is turned yellow by a 

 transverse band often sharply defined, and not running longitudinally 

 down the leaf. This transverse band may be noticed where the beds 

 have been given a heavy top-dressing of manure, and cold weather has 

 arrived and checked the growth after the leaves have begun to push their 



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