Angewandte Botanik. 557 



attacked in 1910, but all have succumbed. Grosses of Asiatic and 

 native showed greater resistance but all have been seriously affected. 

 Chinquapin-European hj^brids are readily affected, but have great 

 recuperative powers. Chinquapin-native Grosses appear very suscep- 

 tible and do not as readily recover. Wild chinquapin appears measu- 

 rably resistant; Asiatic and chinquapin- Asiatic hybrids are plainl}^ 

 highly resistant. 



Especially important for American growers is the chinquapin- 

 Japan hybrid (between C. pumila and C. crenata) for its vigorous, 

 small, much branched trees, Coming into bearing at three \o five 

 years from the seed. While 100 chinquapin-nuts averaged in weight 

 100 grammes, 100 native chestnuts 395 grammes, was the average 

 of 100 chinquapin-Japan hybridnuts 613 grammes. Time of ripening 

 is very early, forestalling even the wild chinquapin, thus preceding 

 all other chestnuts, the crop being wholly mature by October without 

 frost. The quality of these first-generation hybrids is good enough 

 when cured to be enjoyed thoroughly without cooking. The trees 

 also are valuable, highly desirable for lawn planting as well as for 

 nut growing. The germination percentage of the hybrid nuts is 

 rather low, but about half produce vigorous seedlings with very 

 diverse foliage, resembling beech, oak and holly leaves rather than 

 chestnut. Perhaps breeding experiments with a very promising 

 Chinese chestnut, C. mollisshna, will give good results, as the Chinese 

 plant Shows a marked resistance to Endothia-äi'isedse and nuts of 

 really excellent quality. M. J. Sirks (Haarlem). 



Hume, H. H., Planting persimmons. (Journ. of Heredity. V. 

 p. 131 — 138. 1914.) 



The cause of the unfruitfulness and sporadic fruitfulness in some 

 seasons of the Japanese persimmon [Diospyros Kaki) remained very 

 much of a mystery for many years. As is usual in such cases, 

 many theories have been advanced to account for its non-fruiting. 

 Too much cultivation, lack of potash, growth and development of 

 the calyces were all made responsible for the bad results, but none 

 of these theories proved to be right, Flowers of D. Kaki are of two 

 kinds, pistillate and staminate. More than twenty thousand hand- 

 poUinations have fairly demonstrated that pollination will cause 

 fruit to set and grow to maturity. But the production of staminate 

 flowers occurs at irregulär intervals. They may be found on certain 

 trees one season and not the next. Many seasons may elapse before 

 they appear again. It may even happen that never again they are 

 produced, or they are produced every other season. The pollen, 

 produced by a staminate-flowers bearing tree, is also sufficient for 

 the female flowers of many trees surrounding them. It is a fact that 

 trees of all varieties of D. Kaki, in good health and which bloom 

 under normal weather conditions, can be depended upon to bear 

 good crops if pollinated, and it is equally true (a few varieties only 

 excepted) that they will not do so if pollen is not provided. But 

 there are other factors which enter into the problem of barrenness: 

 they may be unhealthy, they may not bloom a. o., but the breeder 

 has these factors in hand for a great extension. Help from the common 

 American persimmon, D. Vir^iniana, cannot be expected, for no 

 viable seed has been obtained of many hundred handpollinations 

 between D. Kaki and D. Virginiaria. They appear to be absolutely 

 incompatible. The variety, which will give probably best results as 



