510 FUNDAMENTALS OF FRUIT PRODUCTION 



which is classified as a perfect flowered variety of the Muscadine group, 

 produces true hermaphrodite flowers only when given proper cultivation 

 and care.^^ Under neglect "its pistils gradually cease to function and 

 the vine assumes the general role of one that is staminate." This is just 

 the reverse of the condition found in the Hautbois race of strawberries, 

 which is reported as perfect flowered and productive when grown under 

 ordinary culture, though in a rich soil the stamens develop poorly and 

 produce little good pollen, the result being a poor setting of fruit. ^* 



The data presented in Table 69 of the section on Nutrition are 

 particularly pertinent. Applications of nitrate of soda to the trees a week 

 or 10 days before blossoming increased the set of fruit by as much as 300 

 per cent in some instances. Data are not available to show just how the 

 fertilizer applications increase fruit setting, though recent investigations 

 indicate that a high nitrogen content in the spur itself favors that 

 process.^^ The results of these and similar experiments in other parts of 

 the country and with other fruits are of far reaching practical importance, 

 for they indicate that fruit setting may be much more completely and 

 directly under control than has been realized. 



Pruning and Grafting. — Pruning and grafting result in a changed 

 environment for at least portions of the plant and in changed nutritive 

 conditions within the entire plant or within certain parts. The general 

 influence of these practices on vegetative growth and fruitfulness is 

 discussed in some detail in the sections on Propagation and on Prun- 

 ing. In addition to those indirect influences on fruit production, how- 

 ever, they often have a more direct influence on fruit setting. Thus 

 Darwin^^ states that plants of Passiflora alata as grown in England are 

 generally self sterile. However, at Taymouth Castle one plant of this 

 species grafted on an unknown variety became entirely self fertile. 

 Pinching the growing tips of the shoots of certain European grape varie- 

 ties when they are 18 to 24 inches long and the blossom bunch is well 

 formed helps materially in the setting of the fruit. ^ Pruning, along with 

 other practices, is reported to be one of the means of keeping the Hope 

 grape (one of the Muscadine group) in a true hermaphrodite condition. ^^ 

 If this is neglected the variety tends to sterihty through a weakening and 

 an abortion of its pistils. The Malta orange grafted on rough lemon or 

 "khatti" stock in Baluchistan produces fruits averaging 16 to 17 seeds; 

 when grafted on the sweet lime the fruits of the same variety average 

 but seven seeds. ^^ In this case the trees have remained fruitful, but 

 fecundity has been modified. Though data on this question as it pertains 

 to deciduous fruits are almost lacking, there is reason to believe that the 

 subject is often of real importance in commercial production. 



Locality. — Fruit setting on trees of the same variety is often much 

 better in one locality than in another. It might be possible to segre- 

 gate the various factors of soil, temperature, humidity, light, etc., 



