151 



Rome Beauty producing with own pollen 

 3 seeds per fruit. Five cross-pollinated 

 varieties produced 5.4 to 6.7 seeds per 

 fruit. A large number of our commercial 

 varieties of apple are self-stevile ; further- 

 more, those that are appai-ently self-fertile 

 or partially so are usually inferior in size 

 to the fruits that set under natural con- 

 ditions. 



Cross-pollination trials are necessary in 

 order to arrive at definite conclusions as 

 to which are the best pollenisers for any 

 commercial variety, there must be mutual 

 affinity between varieties planted to- 

 gether. 



Experiments were made at the Idaho 

 Station in 1915, in order to study this im- 

 portant question. 



Cross-Pollination Results. 



Percentage of fruits 

 set to 100 blossomij 

 cross pollinated. 

 Rome Beauty X Newtown Yellow pollen 10.0 



Rome Beauty X Gravenstein pollen 0.8 



Newtown Yellow X Rome Beauty pollen 15.0 

 Newtown Yellow X Jonathan pollen ... 34.5 



Jonathan X Newtown pollen 27.3 



Jonathan X Rome Beauty pollen 25.7 



Grimes Golden X Wagener pollen 1.3 



Grimes Golden X Mcintosh pollen .^^ qjj g^ 



Wagener X Grimes pollen ^j,g g^g 



Wagener X Mcintosh pollen ' \iish 



Wagener X Gravenstein pollen 0.(5 ,_ 



Mcintosh X Grimes Golden pollen 8.0 '^ 



Mcintosh X Wagener pollen 5.0 



Spitzenburg X Grimes Golden pollen ... 35.0 

 Gravenstein X Wagener pollen 22.5 



These results show that certain crosses 

 give better results than others. Some 

 varieties would appear to be specially well 

 suited to plant together, whilst other 

 varieties should be avoided. To select a 

 good polleniser (1) there should be mutual 

 affinity (2) the two varieties must bloom 

 at approximately the same time; (3) the 

 varieties should be good pollen producers. 



Those who have orchards just coming 

 into bearing, or old orchards for that 

 matter, planted with one or two varieties 

 which are shy pollen producers, should 

 graft one tree at least out of every ten 

 with some variety that is an abundant 

 pollen producer, and blooms at the same 

 time. The final recommendation is to 

 introduce one hive of bees to each acre of 

 apple trees, to carry the pollen from tree 

 to tree. 



