POLLINATION OF THE MANGO. 17 



that some are affected less injuriously by a wet soil than others. 

 Most notable among those which flower under conditions somewhat 

 unfavorable may be mentioned the Sandersha and the Julie of the 

 grafted varieties and the No. 11 race among the seedlings. During 

 the early spring of 191 5, when the weather was unusually wet and the 

 ground was scarcely allowed to dry out, all these came into bloom, 

 while the Mulgoba and numerous other varieties failed to show any 

 signs of bloom until the rains had ceased for a time and the wet spell 

 had been followed by two weeks of dry, sunny weather. It is evident 

 that in many varieties some check to vegetative growth, such as is 

 given by a thorough drying of the soil, is necessary to encourage 

 flowering. While conclusive evidence is lacking, it seems probable 

 that fruit buds are not formed in the mango a long time in advance 

 of the flowering season. This is in contrast to many temperate fruits, 

 such as the apple, in which the fruit buds are formed during the 

 summer, lie dormant overwinter, and appear as flowers in the spring. 

 In the mango no indication of tissue differentiation to form fruit buds 

 has been observed in the vegetative cones of the young branchlets until 

 a very few weeks previous to the appearance externally of the young 

 panicle. Thorough drying of the soil a few weeks before the normal 

 flowering season, therefore, should be efficacious in encouraging the 

 formation of fruit buds, and in practice this has proved many times 

 to be the case. 



The necessary check to growth sometimes is produced artificially 

 in the Tropics by root pruning, hacking the trunk, or other means. 

 It seems highly desirable, however, that the check be produced 

 normally through the drying of the soil, and hence the best mango 

 regions probably will remain those where the normal flowering season 

 occurs at a time of year when the weather is usually dry. It is 

 significant, however, that some varieties seem to require this check 

 to a less degree than others, and this may make possible the cultiva- 

 tion of choice varieties which will be much more regular in fruiting 

 than the Mulgoba when grown under slightly adverse conditions. 



LENGTH OF FLOWERING PERIOD. 



In addition to flowering regularly, even when climatic conditions 

 are somewhat unfavorable, another characteristic is important in 

 connection with flowering, i. e., the length of time during which a tree 

 remains in bloom. This varies greatly in different varieties. Some 

 will develop all their flowers within 10 days from the opening of the 

 first buds ; other varieties, such as the Sandersha and the Julie, keep 

 on developing new panicles of flowers throughout several weeks, or 

 even months, and in 1915 there was not a single day between the 

 middle of January and the latter part of May on which flowers could 



