COMMERCIAL DUTCH-BULB CULTURE. 23 



of handwork involved contributes directly to the possibility of doing 

 a large part of this culling. 



The time when culling can be done to best advantage is while the 

 bulbs are in the bulb house. At this time all imperfect and ques- 

 tionable individuals should be ruthlessly rejected. No stock should 

 be planted which is under suspicion of disease. On the other hand, 

 especially while the grower is working up his stocks, it is necessary to 

 distinguish between imperfections which will result simply in a re- 

 duced yield and those which may cause contamination. For instance, 

 a skinned tulip bulb, even when slightly moldy, may and probably 

 will produce perfectly healthy, although smaller, bulbs than those 

 planted. A healthy reproduction may often occur even when there 

 is no top growth. Consequently, 



it may be highly desirable often /4^4 



to plant bulbs which are of very ^^ t^ ""^ \ 



bad appearance, provided they | ^k 



are not infested with a noxious {? \ 



disease or with insects. Such ' . . 



tulip bulbs will produce again. 1; 



Narcissus bulbs affected with the 

 narcissus fly, however, should be 

 destroyed wherever found; but, 

 even here, one bulb of a clump 

 affected by the fly does not reduce 

 in the least the value of the other 

 bulbs. 



This process of culling should 



,1 • J. J.1 T> ^ Fig. 13. — Narcissus bulbs, showing a good 



be going on constantly. Beds propagation in the sir Watkin variety. 



should be rogued at blossoming 



time, weak plants should be destroyed during the growing season, and 



bulbs of poor quality or found to be infested should be culled out of 



stocks either in storage or in the field whenever and wherever 



detected. 



PROPAGATION. 



All of the classes of Dutch bulbs described in this bulletin can be 

 propagated from seed, but this form of reproduction is used only 

 by the breeder. 



The writers prefer to plant the seed in the autumn in a well- 

 prepared seed bed in a coldframe. The seed should be put in one- 

 half inch deep and mulched with litter, which is removed before the 

 growing season opens. Special care should be exercised to see that 

 there is a constant supply of moisture, so as to prevent the seed from 

 drying out at any time. 



Tulips, narcissi, and hyacinths reproduce naturally in another 

 way also. Upon reaching maturity the bulbs divide into two or 



