758 EXPERIMENT STATION EECORD. 



kinds of nourishment; the fruit l:)uds may ])e injured from winter freezes or late spring 

 frosts; and, finally, blossoms may fail to set fruit from improper pollination. The 

 last factor was made the subject of special investigation daring the season of 1902. 

 Pollination experiments were made in the orchard of the Kansas Agricultural College 

 with a large number of varieties of apples, beginning in most instances practically 

 as soon as the pistillate parent was about three-fourths in bloom. The attempt was 

 also made to use pollen from the staminate parent when the tree was in about the 

 game condition. The results secured show considerable variation in the potency of 

 the pollen of different varieties, both on their own pistils and on the pistils of other 

 varieties. The i)roportion of fruit set to the number of flowers pollinated with jwllen 

 from the variety named was found with a few varieties to be as follows: Ben Davis, 

 25 per cent; Huntsman, 37i per cent; Cooper Early, 37i per cent; Grimes Golden, 

 29 per cent; Jonathan, 52J per cent; Smokehouse, 5 per cent; Missouri Pippin, 33^ 

 per cent; Winesap, 30 per cent; Wine, 29 per cent. This list indicates Jonathan, 

 Huntsman, and Cooper Early as valuable pollenizers for orchards. The data for 

 Ben Davis, as well as for the other varieties, were obtained from 2 or more trees. 

 One hundred blossoms of Ben Davis were covered and thus allowed to fertilize them- 

 selves. Out of this number 26 set fruit. This result is stated to differ from that of 

 Waugh, who found Ben Davis self-sterile. The author states that the self- pollinated 

 Ben Davis fruits were not so large nor so vigorous as those from cross fertilization. 

 The experiments also showed that there was a greater tendency with the self-polli- 

 nated apples to fall from the tree before attaining the size of a hazel nut than with 

 the cross- pollinated fruit. The potency of Jonathan, Cooper Early, and Huntsman 

 was strongly brought out when these varieties were used to cross jiollinate Grimes 

 Golden, Arkansas Black, and Mammoth Black Twig. These latter varieties failed to 

 set a single fruit outside the bags used to cover the cross-pollinated blossoms. 



The variety Jonathan, while standing at the head as a pollenizer of other varieties, 

 was not as potent on its own pistils as Cooper Early. The varietj' Kinnaird was found 

 especially potent on its own pistils. Thirty-five blossoms of this variety were covered 

 with pajier sacks before they opened and produced 35 well-formed fruits. These were 

 but little smaller than the remainder of the fruits on the tree, which was loaded. 

 The Kinnaird is a late-blooming variety and it is hoped that it may have considera- 

 ble value as a pollenizer for Ralls and other late-blooming varieties. 



Attention is called to the fact that varieties listed as shy bearers are those in which 

 the selective power of the pistils is developed to the injury of the fruitfulness of the 

 variety. Thus Jonathan, which is capable of fertilizing nearly every variety in the 

 orchard, responds to but few varieties of pollen itself. Ben Davis, on the other hand, 

 while of little value as a fertilizer for other varieties, responds to almost any variety 

 of pollen. 



In studying the agents of pollination, honeybees were found most useful. The 

 bees work for the most part on the side of the tree away from the wind. With an 

 east wind, 20 l)ees were counted on the west side of a Huntsman tree in full bloom 

 and but 8 on the east side. With a south wind blowing at the rate of 7 or 8 miles 

 per hour, 16 bees were found on the north side and 5 on the south side. Similar fig- 

 ures were obtained at other times with the Kinnaird variety. The bees worked in 

 full sunshine in one case and in shade in another. So far as observed, the bees in 

 every case chose the side of the tree most jarotected from the wind. Bees were noticed 

 to visit the same flower 5 or 6 times within the course of 25 or 30 minutes. While 

 the honeybee was found the greatest agent in pollination, enough other bees w^ere 

 present to insure a crop of fruit when the weather was favorable. 



The extent to which the wind acts as an agent in distributing pollen was deter- 

 mined by exposing prepared microscopic slides at different distances from the tree 

 and at tlifferent heights from the ground. The slides were exposed for varying 

 periods of time and afterwards carefully examined to see how many pollen grains 



