Although Florida grows a majority of the sweet oranges produced in the United States, the orange tree is not a Florida native. Spanish invaders introduced the orange tree to Florida soil in the 16th century, and the trees thrived in the warm climate. Indians and pioneers propagated and transplanted orange trees throughout the warmer areas of Florida.
Because it is a flowering, seed-producing tree, the orange tree belongs to the plant kingdom division angiosperm. The seeds produce two seed leaves when germinated. The leaves have a network of veins radiating from the central vein and the stem has a ring of vascular cambium that further classifies oranges as eudicotyledon or eudicots. The orange tree also belongs to the flowering tree order Sapindales, along with mango, cashew, lychee and neem trees.
The orange is in the same family as many strongly scented herbs of the Rutaceae family. The Rutaceae family is characterized by having oil-filled cavities in the leaves making the plant aromatic. The fragrant, white flowers on orange trees are perfect, or complete, flowers with both male and female reproductive organs on the same flower--a characteristic of plants in the Rutaceae family.
The sweet orange that is cultivated in Florida is part of the genus citrus, which is distinguished by the prevalence of citric acid in the pulpy fruit that is covered by a thick, leathery rind. The fruit has a distinct fragrance and is high in essential oils. The orange tree is a subtropical evergreen tree, which is also a feature of the genus citrus. Oranges are also edible and, therefore, part of the subgenus eucitrus.
More than 90 percent of the oranges grown in Florida are used in juice production. The predominant varieties grown in Florida are Hamlin, Pineapple and Valencia. Hamlin is a high-yielding, cold-tolerant variety that produces small, seedless, juicy pale fruit. The Pineapple variety produces pineapple-scented, high-colored, medium seeded fruit. The Valencia orange is a juicy, richly-flavored orange with a thin rind and is nearly seedless.
The citrus industry is the most important contributor to Florida's agricultural economy. Oranges are Florida's most important crop. Citrus fruit processing--the production of canned juices and fruits--is Florida's leading manufacturing industry.