POLLINATION IN ORCHARDS. 



Z^l 



with pollen. This means that the pistils of 

 the self-sterile variet}- must be receptive 

 when the stamens of the pollinizer are ripe, 

 which is possible only with simultaneous 

 blooming". 



The comparative blooming- of varieties is 

 more or less a local problem. Differences 

 of latitude, altitude, soil, nearness to large 

 bodies of water, and weather conditions 

 during the blooming season not only hasten 

 or retard the time of blooming but also dis- 

 turb the order in which the different varieties 

 open. Varieties blossoming together at one 

 place may not another. The best that 

 can be done in the way of generalizing on 

 the question of simultaneous blooming for 

 cross-pollination is to make a chart for each 

 well marked geographical district. To this 

 end several hundred fruitgrowers have kindly 

 taken notes the past two seasons, and when 

 sufficient data is collected these charts may 

 be published. They will indicate in a general 

 way which of our standard commercial varie- 

 ties may be expected to bloom together ; 

 yet each fruit grower should be prepared to 

 make minor corrections for his own farm. 

 Until more definite knowledge is available, 

 each orchardist should learn how varieties 

 bloom in his own neighborhood before plant- 

 ing them for cross-pollination. It is better, 

 but not always necessan.-, that the two 

 should bloom exactly together ; if they over- 

 lap two or three days that is often enough. 

 It is sometimes desirable to plant varie- 

 ties of different botanical species together for 

 cross-pollination, but this will often be im- 

 practicable because of the difference in their 

 blooming seasons. Thus the Oriental pears, 

 as Kieffer, and the European pears, as Bart- 

 lett, usually do not blossom together. Kieffer 

 generally blooms several days before Bart- 

 lett, hence it necessary to pollinate it with a 

 variety of its own class, as Le Conte or 

 Garber. In some places, however, the two 

 groups blossom approximately together, and 

 then varieties like Bartlett and Seckel should 



be used in preference to Le Conte or Garber, 

 since their fruit has a greater market value 

 and the trees are less likely to blight. 

 Whenever the European pears are used as 

 pollinizers for Kieffer it would be well, if 

 otherwise practicable, to work them on 

 quince roots. Standard Kieffers will often 

 bloom two or three years before standard 

 Bartletts planted at the same time, and 

 unless early blooming dwarfs are inter- 

 mingled they may be unproductive these first 

 few years. 



The three classes of commercial plums — 

 Japanese, domestic and native — will usually 

 bloom at different periods in the order 

 named ; but when a ' ' spell " of warm 

 weather succeeds a cold and backward spring, 

 varieties of all these groups will come on 

 nearly together and cross-pollination will re- 

 sult. In some places the blooming seasons 

 of these groups overlap so that some varie- 

 ties of each might be used regularly for 

 cross-pollination. 



The Mutual Affinity of Varietfes. 



Another point to be looked after when 

 selecting a pollinizer for Kieffer, or for any 

 other self-sterile variety, is the mutual 

 affinity of the two. That is, will the pollen 

 of the pollinizer fertilize the pistils of the 

 self-sterile variety readily and also develop 

 them into high grade fruit ? At present but 

 little is known about- the matter. Taking 

 first the possibility of cross-pollination be- 

 tween varieties of different species, there 

 seems to be no doubt but that many varieties 

 of native Japanese and domestic plums will 

 fertilize each other. Orchard experience in 

 many places indicate this ; as when Satsuma 

 is used to pollinate Coe's Golden Drop in 

 California prune orchards. Several success- 

 ful crosses, between the three were also made 

 at Ithaca the past season. Amongst these are 

 .Abundance x Grand Duke (Fig. 1903), 

 Georgeson x Wayland, Berckman x Coe Gol- 

 denDrop,Coe Golden Drop x Satsuma. That 



