THE GARDEN PRIMER 



blossoms. Down the road three hundred feet is another, 

 its pistillate mate. Once or twice I have found on the 

 latter a fugitive berry or two in the autumn, but this is 

 rare. The two are so far apart that the pollen shed by 

 this tree is lost in the air before it reaches the blossoms 

 on the one yonder — consequently fruit rarely "sets." 



Even with those plants whose flowers are perfect 

 and therefore capable of self-pollination, cross-pollina- 

 tion is better, producing usually seed that germinates 

 into stronger and better plants, or else producing fruit 

 of a decidedly superior quality. Nature therefore has 

 arranged to secure cross-pollination for most things, in 

 one way or another, even though they do produce per- 

 fect flowers. 



Sometimes this is accompHshed by ripening the 

 pistils and the stamens at different times, so that when 

 the pollen is shed the pistil of the flower whose anthers 

 shed it is not capable of retaining it. Some plants 

 indeed are self-sterile and absolutely require pollen 

 from another individual in order to set fruit — many 

 times from another variety. 



There are about sixty species known to be more 

 or less self-sterile, according to the Cyclopedia of 

 American Horticulture. The condition is found 

 among grapes and it is by no means uncommon am.ong 

 orchard fruits. Pears and plums show it most fre- 

 quently perhaps; some apples, while not exactly self- 

 sterile, are much improved by being cross-pollinated 

 with another variety (providing the right variety is 

 chosen), the Baldwin apple being a case in point. 



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