CHAPTEE XLIII. 

 THE POLLINATION, FERTILISATION AND SETTING OF FRUIT. 



The study of plants teaches us that, in 

 order to produce seeds and fruits, pollen 

 needs to be carried from the anthers of 

 the stamens to the stigma of the pistil; 

 wind and insects are the transporters of the 

 pollen. Wind carries the pollen from the 

 catkins to the nut flower in the case of the 

 cob and filbert nut and the walnut ; it also 

 appears to do so largely in the case of 

 strawberry flowers — at any rate in sunny 

 weather. Our other hardy fruits seem to 

 need the visit of insects to carry the pollen 

 from the anthers to the stigmas in order to 

 mature perfect fruits (raspberry and logan- 



insects for the fertilisation and maturing 

 of their fruits. 



In the cherry, plum, apple and pear a 

 large proportion of the varieties are self- 

 sterile, or nearly so ; that is, only a small 

 proportion of the blossoms will mature 

 fruit with pollen of the same variety ; some 

 of the cherries are even inter-sterile — i.e., 

 show preference as to pollen and will not 

 set fruit with every pollen of a different 

 variety; perhaps this is more the case, for 

 some reason, in America than here. Even 

 in more or less self-fertile varieties in 

 nearly all cases a larger proportion, and 



P E A Pv 



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t, apple: .,., plum ■i.uS.S-?.'Jii^J.:..'*?°^^*^5^'' I 



Pollens oe Vabious Fruits. (Magnified about 200 times, i 

 (Photo by F. Edenden, Wye.) 



berry) ; in the gooseberry and red and 

 black currant the pollen is glutinous (like 

 miniature balls of boiled sago) and needs 

 mechanical transference from the anthers 

 to the stigma. In the plum, cherry, apple 

 and pear one might expect the pollen to be 

 carried from flower to flower by the wind, 

 but observation and experiment in Eng- 

 land, America and Australia prove that 

 this is not the case, only exceptionally or 

 to a very, very small extent, and that the 

 blossoms of these trees are dependent on 



in many cases larger fruit, is produced with 

 pollen of another variety. It is therefore 

 advisable, in order to get the largest quan- 

 tity and best quality of fruit in the case of 

 the apple, pear, plum and cherry, to plant 

 two or more varieties of the same kind of 

 fruit in an orchard or plantation, choosing 

 varieties that are in flower at the same 

 time (avoiding planting very early flower- 

 ing with very late flowering sorts), alter- 

 nating the rows with a different variety 

 every two or three rows, or at any rate 



