16 
BULLETIN 28, U. S. DEPARTMENT OF AGRICULTURE. 
secured from a grower in one of the Eastern States and tested at 
Bellingham. Figure li graphically shows the results of the test. 
The flowers from bulbs grown at the garden for three seasons were 
practically perfect and compared favorably with those from im- 
ported bulbs. Mr. John W. Macrae Smith and possibly others se- 
cured similar results with this variety in their early experiments in 
bulb growing near Bellingham. 
Fig. 15. — American-grown and Holland-grown tulips in alternate rows on the trial 
grounds of the United States Department of Agriculture. Beginning on the left, 
rows 1, Keizerskroon, o, Pottebakker White, and 5, Proserpine, are from imported 
bulbs. Rows 2, Keizerskroon, 4, Pottebakker White, 6, Proserpine, are from 
Bellingham-grown bulbs. The bulbs from both sources were ordinary commercial 
stock. Photographed April 20, 1911. 
PROPAGATION. 
The narcissus is propagated by seeds when it is desired to secure 
new varieties. The commercial method of propagation of the nar- 
cissus, however, is by offsets. The increase secured at the garden 
varies, according to the variety, from 99 to 380 per cent, and the time 
required to grow commercial bulbs from slabs is from three to five 
years, depending upon the variety, the size and vigor of the offsets., 
and the conditions under which they are grown. 
