ALFALFA SEED PRODUCTION. 5 
watched a bumblebee tripping the flowers in great numbers and on 
two occasions observed honeybees doing the same thing. 
In artificially tripped flowers Burkill found that 12 out of 34 
tripped set seed; 50 flowers from which the standard had been ° 
removed were artificially tripped and none set seed. The impact on 
the standard, Burkill believes, ruptures the stigma sufficiently to 
insure fertilization in about one-third of the cases. Burkill’s inter- 
esting data on the tripping of alfalfa flowers when vertical force is 
applied to the tip of the keel are quoted in full on page 27 of this 
paper. | 
Hunter+ conducted observations on the relation of the number of 
seeds per pod in alfalfa as correlated with the proximity of domestic 
honeybees. He evidently assumes that- honeybees are capable of 
pollinating the flowers, but he does not record any observations of 
his own on this point. Pods were compared from two fields, one 
within half a mile of a large apiary, the other 25 miles distant from 
any domestic bees, none of which were observed in the latter field. 
Of pods taken half a mile from a large apiary, 87 contained 482 seeds, 
or 5.58 per pod; 80 pods taken 25 miles distant from any colony of 
domestic bees produced 268 seeds, or 3.35 per pod. 
Kirchner,” after pointing out that. the data on the self-fertilization 
of alfalfa are contradictory, gives results of his own experiments at 
Hohenheim, Germany. Of exposed clusters of blossoms, 54 on two 
plants with 432 blossoms produced, August 23, 208 pods, which, 
though they were not perfectly ripe, showed that they contained 
636 well-developed seeds. On the other hand, 21 covered clusters 
of blossoms on the same plants with 166 blossoms produced only 2 
pods with 3 seeds. He concludes that alfalfa flowers are self-sterile, 
and suggests that Henslow’s results were due to some experimental 
error. 
Westgate,’ in 1906, Rreeentod a brief review of the work of Henslow, 
Urban, Burkill, and Karohner, calling attention to the Tencgomnants 
in the results of different Senet tnions and pointing out the need of 
further studies. 
Fruwirth* found that inclosed ie occasionally formed a few 
pods at Vienna, Austria. 
Roberts and Freeman® have recorded results of alfalfa pollination 
experiments at the Kansas Agricultural Experiment Station. Great 
1 Hunter, S. J. Alfalfa, grasshoppers, bees: their felationshie: University of Kansas, Department of 
Entomology, contribution 65, p. 84, 1899. 
2 Kirchner, O. Uber die Wirkung der Selbstbestéubung bei den Papilionaceen. Naturwissenschaft- 
- liche Zeitschrift fur Land- und Forstwirtschaft, Jahrg. 3, Heft 1, p. 9-10, 1905. 
3 Westgate, J.M. A method of breeding a strain of alfalfa from a single individual. American Breeders’ 
Association, Proceedings, v. 2, p. 65-67, 1906. 
4Fruwirth, Carl. Die Ztichtung der Landwirtschaftlichen Kulturpflanzen. Bd.3, Berlin, 1906, p. 189. 
5 Roberts, H. F.,and Freeman, G. F. Alfalfa breeding: materials and methods. Kansas Agricultural 
Experiment Station, Bulletin 151, p. 79-109, 14 fig., 1908. 
