106 HORTICULTURAL SOCIETY OF NEW YORK. 



persons who have worked on the problem have come to the conchision that 

 natural crossing in the oat is rare, but to test the point a large number of 

 flowers were emasculated and left uncovered under favorable conditions for 

 crossing, but no seed was obtained, while at the same time artificial crosses 

 were averaging about 75 per cent, of successes. 



The method of making artificial oat crosses during the season was in 

 general as follows : From six to eight nearly mature spikelets were selected 

 from the upper part of one of the heads of the desired female parent ; the 

 basal flower of each was opened, and the three anthers were removed with a 

 fine pair of forceps, care being taken not to injure the young stigma. The 

 remaining flowers of the spikelets were cut away and the emasculated flowers 

 carefully closed. The neighboring spikelets on the head were removed and 

 the emasculated flowers tied up together in strong tissue paper for protection 

 from the omnipresent English sparrow. This paper was held on with fine 

 copper wire, to which was attached a small marking tag bearing the date. 

 This work was always done in the morning, at which time the anthers that 

 would open in the afternoon could be grasped with the forceps without being 

 ruptured. 



The work of pollination is best done at from i to 3.30 p. m., before which 

 time it is hard to find ripe anthers, while later than this most of the pollen has 

 already escaped. Only fresh pollen was used. Flowers emasculated during 

 the morning of one' day were pollinated the afternoon of the following day, 

 when practically all of the stigmas were in the best receptive condition. On 

 pollinating, the emasculated flowers were opened and a liberal quantity of 

 pollen dusted on the stigma from a dehiscing anther freshly removed from a 

 selected plant of the desired male parent, and the flowers were again closed 

 and all re-enclosed in the tissue paper. A serial number was placed on the 

 label and under this number in the field notebook was placed all the necessary 

 data in regard to the cross. 



Dry, hot weather is fatal to good results with artificial oat pollination. 

 Several hundred crosses made during a dry, hot spell in June yielded less than 

 5 per cent, of grain, while the work during a protracted cool period of weather 

 that followed this yielded above 75 per cent, of successful crosses. 



Premature pollination does not kill the stigma of the oat flower, as in 

 some plants, neither does it prevent fecundation, as flowers emasculated and 

 pollinated two or three days before maturity set seed. 



In oat crossing the time of blooming is naturally important and must be 

 taken into account. While with the great majority of grasses the flowers 

 open in the morning hours, the oat flowers open only in the evening or after- 

 noon. On an average the blooming period extends from 3.30 to 6 p. m., but 

 under exceptional circumstances flowers will open as early as 10 a. m., while 

 in some varieties by 2 p. m. almost all of the stamens that would ripen that 

 day were ruptured within the flower. The flowers close again before dark, 

 and as a rule do not open again, but some few unfertilized stigmas can be 

 found protruding the next day. The unfertilized stigmas retain their fresh 

 appearance for a long time, sometimes for ever a week or ten days, but rarely 

 set seed when pollinated more than four days after maturity. 



The work in selection is being carried on along the same lines as the 



