HAND POLLINATION OF ORCHARD FRUITS. 



177 



is emasculated. When put on in this manner it awaits until the stigma comes 

 into the receptive stage and then germinates and grows down and fecundates 

 the ovules. On the other hand, if delayed till the stigma shows to the eye that 

 it is in a receptive condition the style is likely to break down before the pollen 

 reaches the ovules. Or, in short, it is much safer to put the pollen on the 

 stigma too soon than too late. 



APPLYING POLLEN TO THE STIGMA. 



The question of how the pollen shall be applied to the stigma is one of 

 the important details of the work. The use of a camel's hair brush is usually 

 recommended, while others say that as good results and more rapid work 

 can be done by using the finger. In our experiments, out of 73 blossoms of 

 Wealthy and Grant Crab apples pollinated with the operator's finger, 12 fruit 

 set, or 16^2 per cent., and out of 53 blossoms of the same varieties pollinated 

 with a camel's hair brush, 14 fruit set, or 26 l / 2 per cent. If the supply of 

 pollen is abundant, it can probably be supplied as satisfactorily with the ringer 

 as with the brush, but where the supply is limited and must be used sparingly 

 it is likely that more satisfactory results can be obtained by the use of a brush. 



The most pronounced results obtained were those that favor pollination at 

 the time of emasculation. Also, in collecting pollen, it was found that much 

 better pollen was secured from anthers taken from blossoms before the corolla 

 had opened. In general I believe that more satisfactory results can be 

 obtained from hand-pollination by doing the work earlier than is generally 

 practised. 



Hand-pollination is the highest developed art of the plant breeder. By 

 it he is enabled to control his conditions and establish pedigrees with as much 

 certainty as the animal breeder. Inter-planting, natural crossing and various 

 methods of securing cross-pollination may be practised, but they can never 

 establish positive records that will enable the scientist to establish the laws of 

 plant breeding. The scientific plant breeder must continue to follow hand- 

 pollination, and in orchard fruits in which the generations are so slow in 

 reproducing themselves, it is doubly important: 



The conference then adjourned to the Museum of the New York Botanical Garden. 



