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 jjk 
to plant bulbs which are of very /** 
bad appearance, provided they | ■' J ' % r =>, 
are not infested with a noxious , 
disease or with insects. Such - ,*j 
tulip bulbs will produce again. "V 
Narcissus bulbs affected with the 'J - 
narcissus fly, however, should be jffljb. ■ 
-^*^ 
%: 
destroyed wherever found; but, 
even here, one bulb of a clump *ffr.-& 
affected by the fly does not reduce 
in the least the value of the other / L Wuy^iW^ 
buibs. y^m 
This process of culling should 
i • . , -i -r> -. Fig. 13. — Narcissus bulbs, showing a good 
be going 011 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 
