34 



BULLETIN 71, HAWAII EXPERIMENT STATION 



the pulp, and the peculiar flavor are characters indicating rela- 

 tionship to the mandarin group. The variety probably reached 

 Hawaii from Florida. 



The tree is small and of spreading habit. The branches are thorny, the foliage is rather 

 sparse, and the leaves have rounded apexes. 



Fruit — Matures in the fall and the early winter. Form, round, oblate, tending toward 

 ovate, occasionally necked; greatest diameter, 2 to 2% inches; rind, rough, orange red: 

 segments 7 or 8 ; flesh, coarse, orange colored ; juice, plentiful with agreeable flavor ; central 

 pith, small and open ; seeds, plump, 7 to 18, of greenish color in side. 



West Indian 



The West Indian, also called the Mexican, is grown extensive- 

 ly in the West Indies, Florida, and Mexico. 



The trees are short-lived in Hawaii. They remain shrubby, rarely attaining a height 

 of 10 feet. The twigs are well provided with small, sharp thorns, and with light-green 

 foliage. 



Fruit — Form, oval to oblong; the greatest diameter, 1% to 2% inches; rind, firm, smooth, 

 thin and yellow ; flesh, fine-grained and of green color ; juice, plentiful and translucent ; 

 acid, very strong, the flavor being distinctly of the lime, central pith, open and small ; 

 seeds, few to many, wedge-shaped to pointed. 



Tahiti 



The Tahiti is supposed to be a mutation of the Persian vari- 

 ety of lime. 



The tree attains a height of 15 feet and forms a dense mass of foliage. The leaves 

 resemble those of the lemon. The maturing season of the fruit is during early fall to 

 December. The tree is of easy culture and tends to be prolific. 



Fruit — Form, oblong ; the greatest diameter, 2% to 3% inches ; rind, smooth, firm, and 

 green ; flesh, fine grained and green ; segments, usually 10 ; juice, plentiful, almost colorless 

 and strongly acid in flavor ; central pith, open and small ; seedless. 



SUMMARY 



Hawaii is adapted to the growing of all kinds of citrus, and 

 at one time exported oranges to a considerable extent. The 

 industry began to decline previous to 1870 as a result of the 

 development of the more remunerative coffee, sugar, and live- 

 stock industries. The Mediterranean fruit fly is the most seri- 

 ous obstacle to successful growing in Hawaii, but this pest has 

 been brought under partial control by the use of parasitic insect 

 enemies. 



Seed in the navel orange, Victoria pomelo, and Marsh grape- 

 fruit, which normally are seedless, was observed when nearby 

 seed-producing sweet oranges, pomelos, and grapefruit were in 

 blossom at the same time. Isolated trees of seedless varieties 

 have borne large crops of seedless fruit, a fact that confirms the 

 findings in other investigations and indicates that seedlessness 

 is due to lack of pollination. 



The results of investigations by Bonavia (6), indicating that 

 pomelos, and all kinds of Citrus decumana are more closely re- 

 lated to oranges than to any other citrus species, have been veri- 

 fied by observations at the station. Both oranges and pomelos 

 were found to be less likely to produce seedy fruit when light 

 showers at blossoming time were frequent enough to keep citrus 

 pollen heavy with moisture, and to prevent pollen-carrying in- 

 sects from working among the flowers. 



In Hawaii citrus varieties are vegetatively propagated best 

 by grafting the desired scions on either shaddocks or sour orange 

 stock. The most successful have been side-bark unions in which 

 scions of the current year were united with 10-month old seed- 



