ARTIFICIAL rOLLIK.JION OF JiPPlZS 



Artificial pollination has been a to-oic of jon^id-jrable interest to growers 

 in the Northeast for a ;rood many years. In seasons when the blossoming period is 

 cool and wet and fruit set is apt to be light, the interest m artificial 

 pollination is at its height. Also^ there are still occasional orchards v/here 

 self-unfruitful varieties have been planted in solid blocks and in such places 

 the problem of cross-pollination is on annual one unless some other varieties are 

 planted or top-worked in the block. 



The types of artificial pollination which have been tried and tested 

 experimentally to a certain extent are: (l) hand pollination; (2) pollen spraying; 

 (3) pollen dusting; (4) airplane pollination; (5) pollenbombs; and (6) bee-hive 

 inserts. Of these 6 methods hand pollination has been by far the most reliable to 

 datej 



Hand pollination . This method is time consuming and expensive but may pay 

 for itself v;hen natural means of pollination are inadequate. A grower may 

 purchase pollen or "collect his avm from suitable early blooming varieties such as 

 Astrachan, Duchess, and Wealthy, One should be certain that the variety of pollen 

 obtained is suitable for the variety to be pollinated, Baldwin, R» I, Greening 

 and Gravenstein are varieties which have pollen v/hich is undesirable for cross- 

 pollination purposes. The pollen may be applied vj-ith an artist's ^/^'^ brush which 

 has the bristles clipped off straight and held closely with a small rubber band 

 or with the eraser end of a pencil. Flowers are most receptive immediately after 

 they are open. Pollinating one flower in every 5 or 6 clusters on a heavily 

 blooming tree is adequate. Two or three ounces of pollen by volimie is enough for 

 one acrer For those of you who may viish more detailed information on this method, 

 it may be obtained from the Department of Pomology, University of Massachusetts^ 

 Amherst, Massachusetts. 



Pollen sprayi n;^. Adding pollen to water in a sprayer and applying it as one 

 would a fuiigicide or an insecticide has been unsuccessful. The pollen does not 

 seem to stick to the stigmatic surfaceo Also, the stigmatlc surface is so 

 exceedingly small that the chances of pollen grains landing there are very slight. 

 Tests in V.'ashington indicate that after the pollen has been in water IG to 30 

 minutes its germinability was greatly reduced. In Vermont it was found that 

 pollen T/as practically non-viable after passing through the sprayer. 



Pollen dusting , A bellows type of hand duster has been reported upon by 

 experimenters in V/ashington. They find it exceedingly v^asteful of pollen and apt 

 to result in a very uneven set of fruit unless extreme care is used. Those 

 sections of the tree \vhich were directly in line vj-ith the dust stream may be set so 

 heavily that considerable hand thinning must be done. Apparently this method is 

 better adapted to such fruits as cherries. 



A irplane pollination . In tests conducted in trie 'k/enatchee Valley of 

 tiashington this method has failed to show any increase in set over limbs which i.er^ 

 protected by bags during the airplane dusting period. Some growers in the 

 Northwest have tried this method and felt that a set of fruit resulted because of 

 it. However, the absence of any untreated portions of the treated area often 

 makes it impossible to judge the results. It seems doubtful that this method nas 

 any value, '^•'hen one considers hov; extremely small the stigmatic surfaces are 

 compared to the total surface area of the petals and foliage on a tree it is not 



