Description
The lychee tree is handsome, dense, round-topped, slow-growing, 30 to 100 ft (9-30 m) high and equally broad. Its evergreen leaves, 5 to 8 in (12.5-20 cm) long, are pinnate, having 4 to 8 alternate, elliptic-oblong to lanceolate, abruptly pointed, leaflets, somewhat leathery, smooth, glossy, dark-green on the upper surface and grayish-green beneath, and 2 to 3 in (5-7.5 cm) long. The tiny petalless, greenish-white to yellowish flowers are borne in terminal clusters to 30 in (75 cm) long. Showy fruits, in loose, pendent clusters of 2 to 30 are usually strawberry-red, sometimes rose, pinkish or amber, and some types tinged with green. Most are aromatic, oval, heart-shaped or nearly round, about 1 in (2.5 cm) wide and 1 1/2 in (4 cm) long; have a thin, leathery, rough or minutely warty skin, flexible and easily peeled when fresh. Immediately beneath the skin of some varieties is a small amount of clear, delicious juice. The glossy, succulent, thick, translucent-white to grayish or pinkish fleshy aril which usually separates readily from the seed, suggests a large, luscious grape. The flavor of the flesh is subacid and distinctive. There is much variation in the size and form of the seed. Normally, it is oblong, up to 3/4 in (20 mm) long, hard, with a shiny, dark-brown coat and is white internally. Through faulty pollination, many fruits have shrunken, only partially developed seeds (called "chicken tongue") and such fruits are prized because of the greater proportion of flesh. In a few days, the fruit naturally dehydrates, the skin turns brown and brittle and the flesh becomes dry, shriveled, dark-brown and raisin-like, richer and somewhat musky in flavor. Because of the firmness of the shell of the dried fruits, they came to be nicknamed "lychee, or litchi, nuts" by the uninitiated and this erroneous name has led to much misunderstanding of the nature of this highly desirable fruit. It is definitely not a "nut", and the seed is inedible.
Origin and Distribution
The lychee is native to low elevations of the provinces of Kwangtung and Fukien in southern China, where it flourishes especially along rivers and near the seacoast. It has a long and illustrious history having been praised and pictured in Chinese literature from the earliest known record in 1059 A.D. Cultivation spread over the years through neighboring areas of southeastern Asia and offshore islands. Late in the 17th Century, it was carried to Burma and, 100 years later, to India. It arrived in the West Indies in 1775, was being planted in greenhouses in England and France early in the 19th Century, and Europeans took it to the East Indies. It reached Hawaii in 1873, and Florida in 1883, and was conveyed from Florida to California in 1897. It first fruited at Santa Barbara in 1914. In the 1920's, China's annual crop was 30 million lbs (13.6 million kg). In 1937 (before WW II) the crop of Fukien Province alone was over 35 million lbs (16 million kg). In time, India became second to China in lychee production, total plantings covering about 30,000 acres (12,500 ha). There are also extensive plantings in Pakistan, Bangladesh, Burma, former Indochina, Taiwan, Japan, the Philippines, Queensland, Madagascar, Brazil and South Africa. Lychees are grown mostly in dooryards from northern Queensland to New South Wales, but commercial orchards have been established in the past 20 years, some consisting of 5,000 trees.
Madagascar began experimental refrigerated shipments of lychees to France in 1960. It is recorded that there were 2 trees about 6 years old in Natal, South Africa, in 1875. Others were introduced from Mauritius in 1876. Layers from these latter trees were distributed by the Durban Botanical Gardens and lychee-growing expanded steadily until in 1947 there were 5,000 bearing trees on one estate and 5,000 newly planted on another property, a total of 40,000 in all.
In Hawaii, there are many dooryard trees but commercial plantings are small. The fruit appears on local markets and small quantities are exported to the mainland but the lychee is too undependable to be classed as a crop of serious economic potential there. Rather, it is regarded as a combination ornamental and fruit tree.
There are only a few scattered trees in the West Indies and Central America apart from some groves in Cuba, Honduras and Guatemala. In California, the lychee will grow and fruit only in protected locations and the climate is generally too dry for it. There are a few very old trees and one small commercial grove. In the early 1960's, interest in this crop was renewed and some new plantings were being made on irrigated land.
At first it was believed that the lychee was not well suited to Florida because of the lack of winter dormancy, exposing successive flushes of tender new growth to the occasional periods of low temperature from December to March. The earliest plantings at Sanford and Oviedo were killed by severe freezes. A step forward came with the importation of young lychee trees from Fukien, China, by the Rev. W.M. Brewster between 1903 and 1906. This cultivar, the centuries-old 'Chen-Tze' or 'Royal Chen Purple', renamed 'Brewster' in Florida, from the northern limit of the lychee-growing area in China, withstands light frost and proved to be very successful in the Lake Placid area–the "Ridge" section of Central Florida.
Layered trees were available from Reasoner's Royal Palm Nurseries in the early 1920's, and the Reasoner's and the U.S. Department of Agriculture made many new introductions for trial. But there were no large plantings until an improved method of propagation was developed by Col. William R. Grove who became acquainted with the lychee during military service in the Orient, retired from the Army, made his home at Laurel (14 miles south of Sarasota, Florida) and was encouraged by knowledgeable Prof. G. Weidman Groff, who had spent 20 years at Canton Christian College. Col. Grove made arrangements to air-layer hundreds of branches on some of the old, flourishing 'Brewster' trees in Sebring and Babson Park and thus acquired the stock to establish his lychee grove. He planted the first tree in 1938, and by 1940 was selling lychee plants and promoting the lychee as a commercial crop. Many small orchards were planted from Merritt's Island to Homestead and the Florida Lychee Growers' Association was founded in 1952, especially to organize cooperative marketing. The spelling "lychee" was officially adopted by the association upon the strong recommendation of Professor Groff.
In 1960, over 6,000 lbs (2,720 kg) were shipped to New York, 4,000 lbs (1,814 kg) to California, nearly 6,000 lbs (2,720 kg) to Canada, and 3,900 lbs (1, 769 kg) were consumed in Florida, though this was far from a record year. The commercial lychee crop in Florida has fluctuated with weather conditions, being affected not only by freezes but also by drought and strong winds. Production was greatly reduced in 1959, to a lesser extent in 1963, fell drastically in 1965, reached a high of 50,770 lbs (22,727 kg) in 1970, and a low of 7,200 lbs (3,273 kg) in 1974. Some growers lost up to 70% of their crop because of severe cold in the winter of 1979-80. Of course, there are many bearing trees in home gardens that are not represented in production figures. The fruit from these trees may be merely for household consumption or may be purchased at the site by Chinese grocers or restaurant operators, or sold at roadside stands.
Though the Florida lychee industry is small, mainly because of weather hazards, irregular bearing and labor of hand-harvesting, it has attracted much attention to the crop and has contributed to the dissemination of planting material to other areas of the Western Hemisphere. Escalating land values will probably limit the expansion of lychee plantings in this rapidly developing state. Another limiting factor is that much land suitable for lychee culture is already devoted to citrus groves.
Varieties
Professor Groff, in his book, The lychee and the lungan, tells us that the production of superior types of lychee is a matter of great family pride and local rivalry in China, where the fruit is esteemed as no other. In 1492, a list of 40 lychee varieties, mostly named for families, was published in the Annals of Fukien. In the Kwang provinces there were 22 types, 30 were listed in the Annals of Kwangtung, and 70 were tallied as varieties of Ling Nam. The Chinese claim that the lychee is highly variable under different cultural and soil conditions. Professor Groff concluded that one could catalog 40 or 50 varieties as recognized in Kwangtung, but there were only 15 distinct, widely-known and commercial varieties grown in that province, half of them marketed in season in the City of Canton. Some of these are classed as "mountain" types; the majority are "water types" (grown in low, well-irrigated land). There is a special distinction between the kinds of lychee that leak juice when the skin is broken and those that retain the juice within the flesh. The latter are called "dry- and -clean" and are highly prized. There is much variation in form (round, egg-shaped or heart-shaped), skin color and texture, the fragrance and flavor and even the color, of the flesh; and the amount of "rag" in the seed cavity; and, of prime importance, the size and form of the seed.
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