THE PRODUCTION OF NARCISSUS BULBS 13 
jurious to the stocks. It is better to plant the clumps and wait for 
nature to make the separation, which will take place without a 
serious wound and with less injury to the bulbs. 
SIZERS AND SIZING 
As stated elsewhere, the separation of the merchantable from the 
planting stock, which involves also the breaking apart of the bulb 
clump, is essentially handwork. The operations can not be done by 
any machinery yet invented. This accomplishes a large part of the 
sizing, and in practice it is believed that the separation of the large 
bulbs can best be done at the time the clumps are broken, as in tulips. 
In commerce there are three main qualities of these bulbs, depend- 
ing partly but not wholly upon size: (1) Double nosed, (2) first 
size, and (3) second size. The first will usually give two flowers, 
the second is the largest single-flowered bulb, and the third is a 
smaller flowering size. In all of these categories there is a flexible 
rather than a fixed standard of size, for each category is variable and 
must differ with the variety and also with the conception and in- 
tegrity of the seller. It also varies from year to year with the crop. 
The separation of the merchantable from the planting stock at the 
time that the clumps are broken is described here because in the 
writer's experience it is economy to make the separation at this time. 
The further separation of the salable stock by some mechanical sizer 
into the three categories mentioned above is considered elsewhere, 
but perfect segregation of the double-nosed bulbs is difficult to make 
mechanically because some double-nosed bulbs may be smaller than 
first-size single-nosed ones, necessitating again considerable hand- 
work. The process, however, is not so laborious as its discussion 
would indicate, and it must be considered a matter of as great im- 
portance in the bulb industry as are close sizing and grading in the 
various fruit industries. 
In these experimental investigations the only sizer now used is one 
consisting of a series of parallel bars in the form of a grating. (PL 
IV, fig. 1.) The series of bars form the surface of an inclined plane 
about 16 feet long, having a compartment under each separate grat- 
ing for the reception of the bulbs that pass through that grating. 
The bulbs are worked by hand over this series of bars, one man work- 
ing on either side of the incline. Only the planting stock is handled 
in this machine. 
Attention should be called to the difference in performance be- 
tween this form of sizer and one consisting of round perforations in 
a parchment or other thin plane. The grating measures the shortest 
diameter of the bulb, while the round hole measures the longest 
diameter in the case of somewhat flattened bulbs. Another dif- 
ference is likely to be overlooked from the fact that in the use of 
the ordinary parchment sieves used for sizing tulips and described 
in a previous bulletin 3 the bulbs take the size of the sieve on which 
they are caught, while in the grating they take the size of the grating 
through which they pass. In order to make the two systems more 
comparable it is necessary to step the grating system down 1 centi- 
meter, or one size, in order to approximate the round perforation. 
3 Griffiths, David. The production of tulip bulbs. U. S. Department of Agriculture Bul- 
letin 1082, 48 p., 20 pi. 1922. 
