20 BULLETIN 1462, TJ. S. DEPARTMENT OF AGRICULTURE 
DISEASES, PESTS, AND UNFAVORABLE CONDITIONS 
During the season of 1924 special attention was paid to the pos- 
sible appearance of diseases in the stocks received from different 
sections. Some daffodil bulbs were submitted with the request that 
this attention be given, the nematode disease being specifically men- 
tioned. In the last three years stocks of daffodils from 13 States 
have been forced. Xone of them was infested with this malady, 
although the disease is known to exist in some localities from which 
bulbs were forced. 
A few daffodil bulbs were gray, but not many. A discussion of 
this malady is found under the consideration of Sir Watkin, on page 
8, and a more complete treatment in United States Department of 
Agriculture Bulletin 1270, The Production of Narcissus Bulbs. 4 
The large daffodil fly (Merodon equestris) was received from two 
sources and the lesser fly (Ewnerus strigatus) from one source in 
tulip bulbs. 
On the whole, the most serious and destructive maladies of daffo- 
dils are those brought about by untoward conditions of culture or 
handling. It is useless to attempt to produce good daffodils over an 
impervious subsoil which keeps the roots in stagnant moisture during 
the wet season. Eaw manures are also inimical to healthfulness of 
the stocks. Either of these conditions will produce basal rots and 
" ring diseases," which are sure to cause alarm and are likely to 
be interpreted as caused by parasitism, when in reality they are a 
reaction to improper environment and disappear when these condi- 
tions are rectified. 
Another very potent cause of trouble is improper storage condi- 
tions, resulting in heating, bruising, or overexposure of the bulbs. 
Some growers dig the bulbs before the tops die and throw the daffo- 
dils into piles, turning these over as the tops decay to prevent " too 
much heating." Such stock will not keep on the merchants' shelves 
any more than will daffodil stocks burned in the sun or those bruised 
in handling. The writer has seen a 75 per cent loss in daffodil bulbs 
caused by rough screening at harvesting time. About 25 per cent 
of the rotted bulbs were literally filled with the larvae of the lesser 
narcissus fly, and the remainder were free of it. 
The economical handling of large quantities of daffodil bulbs in 
storage is difficult to direct, for the reason that the crop is very 
bulky and furthermore because improper storage leads to alarming 
disease. The writer has previously stated that it may be seriously 
questioned whether it is economically practical to shelve a mass pro- 
duction of daffodil stocks, because they must be handled so that they 
are neither heated, bruised, sunned, nor dried out too much. Any of 
these excesses leads to " diseased " conditions which impair the stocks. 
Excessive drying, however, is much less dangerous than poor aera- 
tion with danger of heating. 
The Department of Agriculture has been able to dry and keep 
successfully Emperor and King Alfred daffodils in slatted crates 
holding 1 bushel each, in the climate of Washington, D. C. The 
bulbs were dug after the tops were well dried, and were put directly 
* Griffiths, D. The production of narcissus bulbs. U. S. Dept. Agr. Bui. 1270, 
32 pp., illus. 1924. 
