366 MANUAL OF TROPICAL AND SUBTROPICAL FRUITS 



flat heads and round bodies. That they are at work in a tree may 

 be known by the discolored bark and by gum oozing from the trunk 

 or branches. Cut away the bark with a sharp knife or chisel and 

 destroy them. Paint the wounds thus made with good, thick, white- 

 lead paint. Carefully paint all wounds when made, and scrape 

 the rough-barked places on young trees. By careful attention to 

 wounds on the trees, they may be prevented from entering, and 

 the trees will live to a good old age." 



Varieties. 



Although 800 varieties are grown in Japan, Ikeda does not 

 consider more than 90 to be valuable. In the United States 

 the number offered by nurserymen is relatively small. The 

 nomenclature of the horticultural varieties in Japan is some- 

 what confused, and doubtless nurserymen have multiplied the 

 names. China possesses a considerable number of varieties, 

 but relatively few of them are yet known in the United States. 



Japanese writers classify kakis according as they are sweet 

 or astringent. Hume points out that such a classification is not 

 tenable, inasmuch as certain varieties fall in the sweet group 

 when carrying seeds and in the astringent group when seedless. 

 He writes in the Journal of Heredity for September, 1914 : 



" Based on the difference in flesh coloration under the influence 

 of pollination, kaki may be divided into at least two groups, first, 

 those which show no change of color of flesh under the influence of 

 pollination, and, second, those in which the flesh of the fruit is dark- 

 ened under the influence of pollination. Since the change in color 

 in the one case is directly due to pollination and in the other pollina- 

 tion has no effect whatever, we shall refer to those varieties which 

 undergo no change in color as Pollination Constants and those which 

 are light colored when seedless and dark colored when seedy we shall 

 call Pollination Variants. Now, all varieties of D. kaki growing in 

 this country or elsewhere may be referred to one or the other of these 

 groups. If varieties which are constantly dark-fleshed whether seedy 

 or seedless should be found, the group of Pollination Constants can 

 then be divided into two groups of light- and dark-fleshed Pollina- 

 tion Constants. It is hardly probable that there are varieties which 

 are dark-fleshed when seedless and light-fleshed when seedy, but if 

 any such should be discovered a similar plan can be followed by divid- 

 ing the group of Pollination Variants." 



