Aprii., 1922 



GLEANINGS IN BEE CULTURE 



227 



^roiitly increased when several colonies of 

 bees were placed in the orchard. It is in- 

 teresting to note that this ranch today 

 keeps a large number of bees and produces 

 large crops consistently year after year. Yet 

 on other ranches in the same section where 

 crops were erratic, the owners did not be- 

 lieve that bees were in any way responsi- 

 ble. In spite of this information printed in 

 the reports of the State Commission of Hor- 

 ticulture and hence available to the county 

 commissioners and others, many growers had 

 no conception of the importance of these 

 useful insects. Many ranchers went to the 

 opposite extreme and disposed of their 

 bees, claiming they were a nuisance at dry- 

 ing time and generally hard to care for. In 

 1916 and 1917 the University of California 

 by means of tents of mosquito netting over 

 prune trees proved conclusively the value 

 of bees in prune orchards. Since that time 

 the use of these insects in the Santa Clara 

 Valley and elsewhere has steadily increased. 

 In 1921 the results of similar experiments 

 demonstrated to the Placer County growers 

 the need of bees for their plums. From in- 

 terest shown thus far it would seem that 

 this district would be a promising field for 

 an energetic beeman with several hundred 

 colonies to rent. 



Process of Fertilization. 



Before proceeding further, it would be 

 well to stop and consider briefly what is 

 necessary to secure a set of fruit. The im- 

 portance of bees is more fully realized when 

 the intricate process of fertilization is un- 

 derstood. Assuming that the orchard has 

 been given normal care, the trees will blos- 

 som in a satisfactory manner at the proper 

 time. Each blossom produces one or more 

 pistils, as the case may be; a large number 

 of stamens; a row of showy white or pink 

 petals; and, on the outside, a row of green 

 sepals. The important organs are the first 

 two, the petals being largely for show. The 

 pistil, or female portion, consists of a young 

 fruit in which is located the unfertilized 

 egg, and above which is a rather long slen- 

 der stalk surmounted by a flattened sticky 

 surface called the stigma. The stamens, or 

 male elements, are long slender filaments 

 bearing the anthers, which enclose large 

 quantities of pollen. Deep down in the flow- 

 er is usually the nectary which secretes the 

 honey. At the proper time the pollen falls 

 upon the stigma, germinates, and sends 

 down a tube thru the pistil to the egg. The 

 male nucleus passes into the egg and unites 

 with the female nucleus, completing the 

 process of fertilization. Under this stimu- 

 lus the young fruit develops very rapidly. 

 If the egg is not fertilized in a compara- 

 tively short time, it shrivels and the young 

 fruit turns yellow and falls to the ground. 



The egg or young ovule remains receptive 

 for perhaps several days, depending some- 

 what upon the climatic conditions. If not 



fertilized during that time it begins to dis- 

 integrate and the young fruit is doomed to 

 fall. Many potential fruits are lost each 

 year because the egg was beyond the recep- 

 tive stage before the pollen tube reached it. 

 Thus, the rate of growth of the pollen tube 

 down the style becomes a very important 

 factor. If the growth is slow, disintegra- 

 tion of the egg may commence before the 

 nucleus can pass over and complete the pro- 

 cess of fertilization. Experiments have 

 shown that pollen tubes grow much slower 

 in cold weather than in warm, which may 

 help to account for light crop following cold 

 springs. Pollen tubes also grow much 

 slower in self-pollinated flowers than in 

 cross-pollinated ones. Self-pollinated fruits 

 are those pollinated with the pollen from 

 the same variety. Cross-pollinated fruits 

 are those produced when pollen from an- 

 other variety is used. This slow growth 

 may be one of the fundamental causes of 

 sterility among deciduous-tree fruits. For 

 full setting it would seem that the ideal con- 

 ditions would be fairly warm clear weather 

 and ample facilities for cross-pollination, so 

 that a strong, active growth would be se- 

 cured in the pollen tubes. 



In addition to this impediment to self- 

 pollination just described, nature has also 

 provided others which are more obvious. 

 Many fruits like the plum and apple do not 

 have the pistil and stamens maturing at the 

 same time. While the pistil is receptive, 

 the pollen is not yet mature. Consequently 

 pollen from another variety must be placed 

 on the pistil to secure fertilization. An- 

 other factor is the one of difference in 

 length of the important organs. In certain 

 varieties of almonds, cherries and plums the 

 pistil is so much longer than the stamens 

 that there is no possibility of the pollen 

 dropping on the stigma. An exception to 

 this rule seems to be the apricot and possi- 

 bly the peach. With but few exceptions the 

 pollen must be transferred mechanically to 

 the stigma of the same or difi'erent flowers. 

 Insects and wind are the only two distrib- 

 uting agents worthy of mention. For prac- 

 tically all of our tree fruits except walnuts, 

 wind as a pollen carrier may be considered 

 as practically negligible in value. Insects 

 are the effective pollen carriers. No one 

 knows exactly of what importance each one 

 is, but the honeybee is usually considered 

 the most valuable. Increased crops, due to 

 the addition of bees to the orchard, is am- 

 ple proof of this statement. 



Fruits Requiring Cross-Fertilization. 



Bees are a vital necessity with many va- 

 rieties of fruits, and are very helpful with 

 nearly all others. Among the fruits which 

 are benefited by bees are almonds, apples, 

 cherries, pears, plums and prunes. Shy bear- 

 ing in almonds, for a time attributed to 

 cold weather and similar causes, is largely 

 due to lack of cross-pollination. In bulletin 



