Anne Schwartz, age 12, of Glendale, Ariz., for her question:
HOW MANY LEMONS WILL A LEMON TREE PRODUCE?
Lemon is a small thorny citrus tree that is cultivated throughout the tropical and subtropical regions of the world. Lemon trees are found particularly in California, Italy, Spain and Portugal. More mature lemon trees may produce between 1,000 and 2,000 fruits each year.
In the United States, some lemons are produced in Arizona and Florida, but almost ail commercial crops are grown in Southern California. The production of California lemons averages about 95 per cent of the annual United States output.
The main types of lemons produced in the U.S. are the Eureka, the Lisbon, the Genoa, the Sicily, the Belair and the Villafranca.
The cultivated lemon is probably a hybrid of two wild species of citrus. The probable parent species were lime and citron.
Most cultivated lemon varieties are hybrids that produce little or no true bred seed. Propagation in commercial lemon orchards is usually accomplished by grafting lemon buds onto seedlings of related species, such as orange or grapefruit.
The trees are planted in fertile soil to which fertilizer is continually added. The rows of trees in a lemon grove are spaced from 15 to 25 feet apart, depending on the variety planted and the climate and topography of the region.
Except when extreme temperatures delay blooming, fruits are produced throughout the year. Green, almost ripe fruit is picked from each tree six to 10 times yearly and ripened at moderately warm temperatures.
Lemon trees grow about 10 to 20 feet tall and are sparsely covered with foliage. The flower has five petals, numerous stamens and a solitary pistil. The upper surface of each petal is white and the lower surface is pinkish. Lemon flowers have a sweet odor comparable to, but less marked that, the odor of orange flowers.
The lemon fruit is a pale yellow, elliptically shaped berry, which usually has a small, nipple like protuberance at the apex. The exocarp layer is the leathery rind, containing oil of lemon, which is used in the manufacture of perfumed and lemon flavoring.
The nearly tasteless, spongy, white layer beneath the rind comprises the mesocarp, which contains a substance called citrin or vitamin P. The pulp, which comprises the endocarp layer, consists of eight to 10 segments containing small, pointed yellowish white seeds.
Lemon juice is used widely as a drink and as a component or part of drinks, salad dressings and fish dressings and as a flavoring.
Lemon pulp is also used in making concentrated lemon juice, which is used medicinally for its high vitamin C content.
Lemon trees were first brought from the Middle East to Spain and northern Africa during the Middle Ages.