Pollination in Orchards. 



381 



pollinizer to 2)rodiice pollen, its market value, and tlie class of fruit 

 to wliicli the self-sterile variety belono-s. 



Varieties differ in the amount of pollen which thej produce, and 

 the pollen production of the same variety is also greatly modified 

 by differences in locality and season. Other things being equal, the 

 variety which produces pollen freely could be used more sparingly 

 in a block of self-sterile trees than one of scanty pollen production. 



84. — Abundance. From Abundance pollen above, from Grand Duke 'pollen 

 beloiD. Some benefit from cross-poUination. 



Little comparative observation has been made on this point as yet ; 

 but, as a matter of fact, most of our common varieties produce an 

 abundance of pollen. 



The number of trees of the pollinizer would also depend largely 

 on whether it has value in itself. If we are planting LeConte to 

 pollinate Kieffer, we would naturally try to get along with the 

 least possible number which will do the work ; but if Bartletts 

 are to be used for the same purpose, we can afford to increase the 

 proportion. Some growers plant every tenth row to the polli- 

 nizer, but the proportion should usually be greater- This mie:ht be 



