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ENCYCLOPEDIA OF PRACTICAL HORTICULTURE 



lighter frosts have touched them. The 

 advancement or retardation of the buds 

 may account for this. Though neither 

 the pistil nor the stamens are badly in- 

 jured by the frost, the ovary may be so 

 badly injured that fecundation is impos- 

 sible. Heavy frosts during the blossom- 

 ing period may so impair the fruiting 

 organs as to cause the dropping of the 

 fruits after they have set. 



4. The trees may lack proper nour- 

 ishment. — This may be from a lack of 

 water or it may be from a lack of other 

 plant foods. Orchards which have been 

 improperly cultivated, or which have 

 grown heavy crops of apples and have 

 not had the elements removed by 

 these crops returned, may fail to set 

 fruit buds in the proper manner. In an 

 experiment with pollen from an improp- 

 erly nourished Missouri Pippin, it was 

 found that this pollen was very much 

 less potent than the pollen from a more 

 thrifty tree. Poorly nourished trees were 

 found to be more liable to self-sterility. 

 Many orchards set in the early history 

 of the different sections have ceased 

 bearing, in all probability from the 

 effects of continued starvation, and many 

 other younger orchards fail to set fruit 

 from the same cause. 



5. The trees may fail to set fruit 

 from an excess of certain kinds of nour- 

 ishment. — The above may be the case or 

 they may have plant food at the wrong 

 season of the year. It is a well known 

 fact that the reproductive and the vege- 

 tative powers of a tree are exercised in 

 direct opposition to each other, and a 

 tree making too great a vegetative 

 growth is liable to be barren. This is 

 especially true of orchards planted close 

 to barns, feed-lots or corrals, where the 

 owner is in the habit of dumping ma- 

 nures. Under such favorable conditions 

 to the development of the vegetative 

 portion of a tree, it would be much 

 longer in reaching maturity and would 

 never bear as well as another tree plant- 

 ed in soil with nearer the optimum 

 amount of plant food or with plant food 

 better adapted to its needs. On such a 

 tree the fruit buds would be few and 



would go into winter in an immature 

 condition, with few chances of escaping 

 winter injury. Orchards may fail to set 

 fruit because of too great a growth dur- 

 ing the season when fruit buds are form- 

 ing. A later fall growth may open the 

 road to winter injury because of im- 

 proper ripening of the wood. Winter 

 killing of the immature wood, together 

 with the fruit buds, is very often the 

 result. 



6. Blossoms may fail to set fruit from 

 improper pollination. — Though the trees 

 may be in perfect health, the winter may 

 not have been severe and the orchard 

 may be a mass of bloom, there may be 

 only a fraction of a crop. Isolated trees 

 which are self-sterile cannot set a full 

 crop of fruit because so few bees, the 

 only agents of pollination acting at a 

 distance, visit two trees very far apart 

 during the same absence from the hive, 

 and very few of the blossoms would thus 

 be fertilized. The same would be true 

 of large blocks of trees planted to single 

 varieties. The bees would carry little 

 else than the pollen of that variety. An- 

 other case of improper pollination is 

 noticed when the weather is damp and 

 cold during the blossoming period. Such 

 weather prevents the work of bees and 

 often causes the germination or the 

 decomposition of the pollen grains. Even 

 when the pollen grains are not entirely 

 spoiled, may it not happen that when 

 slightly wet pollen falls on the stigma 

 it possesses just enough vitality to ger- 

 minate and start fecundation, but not 

 enough to carry it through all the 

 changes necessary to complete fertiliza- 

 tion? If such be the case, the pistil 

 after responding would waste away. 

 Vigorous pollen would thus be prevented 

 from fertilizing the pistil, when the 

 weather became bright and warm enough 

 to properly ripen the pollen and bring 

 out the bees, and fruit would fail to set 

 as it should. 



Dry, hot and windy weather may so 

 badly injure the stamens that they can- 

 not properly mature their pollen or it 

 may cause the dehiscence of the anthers 

 before the pollen is mature. The same 



