CITRUS CULTURE IN HAWAII 



23 



Washington Navel 



The Washington Navel was introduced into Hawaii from Cali- 

 fornia by private growers and by the station. About 1906 the 

 station trees were grafted on sour orange, grapefruit, and sweet 

 orange stock. Since then many trees have been propagated. 

 With good culture the variety produces excellent fruit. 



The trees are rather dwarfed and have few thorns. 



Fruit — Form, roundish, slightly tapering at apex; diameter, 2% to 3% inches; color, 

 yellow ; surface, smooth to pebbled ; rind, thin ; juice, orange-colored, abundant, with acidity 

 and sweetness well blended ; seed, none to few. 



Thompson Navel 



The Thompson is a variety of navel orange and about 1891 

 was introduced to the trade by A. C. Thompson, of Duarte, Cali- 

 fornia. It has been extensively grown in Hawaii, and has proved 

 to be decidedly better than other navel varieties. 



Fruit — Size, medium ; rind, smooth and thin ; pulp, yellow and of fine texture ; juice, 

 abundant and of good quality ; seed, none to few. 



Buckeye Navel 



The Buckeye Navel is occasionally found in cultivation in Ha- 

 waii, but has no advantages over the Washington Navel or the 

 Thompson. The trees of the three varieties are similar in form 

 and in growth, but the fruit differs in shape, and the rind is 

 thinner. The early fruit of the Buckeye often contains a number 

 of spontaneous chimeras. As the ovary grows, ridges, usually 

 reaching from the base to the stigmatic point, develop. Varia- 

 tion is not due to cross-pollination, and cannot be definitely es- 

 tablished by vegetative propagation. Similar sectional chimeras 

 occur in the Valencia orange and in the lemon. 



Fruit — Size, medium ; rind, smooth, thin, and tough ; pulp, fine-grained ; juice, of good 

 flavor; normally seedless, but may become pollinated from other citrus and produce 1 to 15 

 seeds. 



VARIETIES OF MANDARINS 



Mandarin varieties are so different from other oranges as to 

 be classified as a different species (Citrus nobilis). The Nobilis 

 fruit is so called because of its quality. The trees are compara- 

 tively small, but vigorous and prolific ; the branches have numer- 

 ous slender twigs, and the leaf petioles are edged with very nar- 

 row wings ; the flowers are small and white ; the fruit usually is 

 rough, has a distinctive aroma, and is of sweet and pleasing 

 flavor. At maturity the rind is freely separated from the flesh. 

 Hume {18, p. 39), who made a comprehensive study of citrus 

 fruits, states that from the conclusions of De Candolle, man- 

 darins may be considered as natives of Cochin China. A number 

 of varieties are in cultivation in southeastern Asia, the East 

 Indian Islands, and Japan. The species was introduced into Eu- 

 rope in 1805, and into Louisiana about 1850, whence it spread to 

 Florida and to California. 



The Hawaii station in 1906 introduced budded plants of the 

 varieties Dancy, Satsuma, Willow-leaved, and King from Cali- 

 fornia. Representatives of these are still growing in the station 

 orchard and have been the basis of study of the varieties under 

 Hawaiian conditions. Like most other citrus, the varietal char- 

 acters are found mainly in the fruit. 



