39 



no other variety near to it from which pollen could be 

 carried by seed. Even in orchards, if a large number of 

 self -sterile varieties are grown close together, the yield of 

 fruit may not be found to be satisfactory. In both cases 

 it has proved very efficacious to plant near such trees a 

 Siberian or other Crab Apple, which produces a large 

 amount of effective pollen which can be carried by insects 

 from tree to tree. 



After fertilisation, when the young plant is beginning 

 to be formed in the seed, the seed vessel too begins to 

 swell, and it is from observing the latter that we can 

 gather that pollination has been successful. Of course 

 the continued growth of the seed-vessel, as well as the 

 development of the embryonic plant and the storage in the 

 seed of enough food material for its subsequent germina- 

 tion, necessitates considerable activity on the part of the 

 vegetative organs particularly of the leaves. It is for this 

 reason advisable in the case of Peas, Scarlet Runners and 

 French Beans, when they begin to set their pods, to 

 encourage their further growth by the use of suitable 

 stimulants such as liquid manure. 



It is obvious that as the formation of seeds and fruits 

 require increased supplies of food material, herbaceous 

 plants that are heavily fruiting will have less food where- 

 with to develop new flower buds, and graduallv the plant 

 will cease to produce flowers. If, therefore, we are culti- 

 vating plants for the sake of their flowers it cannot be 

 too strongly recommended to pluck oft all flowers as soon 

 as they are dead, so that they should not begin to set 

 their seeds. In the case of Sweet Peas, where the seeds 

 take up a large amount of food material, this is par- 

 ticularly important, but it is a good rule to follow in all 

 cases. The fact that a large supply of food material to 

 fruits may exhaust that available for the production of 

 flower buds will explain reduction m the number of 

 flowers on fruit trees, if an abnormally heavy 

 crop of fruit was produced in the previous season. 

 It is not, however, only the formation of flowers 

 which will be interfered with. Under special cir- 

 cumstances the vegetative organs, too, may suffer. 

 For this reason it is recommended that young 

 fruit trees, which have been recently transplanted, should 

 not be allowed to ripen many of their fruits during the 

 first season after transplantation, as this may interfere 



