Gonzalo Hernandez de Oviedo, who was one of the first Europeans to study the plants of the New World, called the sapodilla the best of all fruits. More recently, Thomas Firm-inger, an English horticulturist who lived in India, wrote of it that "a more luscious, cool, and agreeable fruit is not to be met with in this or perhaps any country in the world"; while the poetic French botanist, Michel Etienne Descourtilz, has characteristically described it as having "the sweet perfumes of honey, jasmine, and lily of the valley"
While it is scarcely possible to indorse the enthusiastic opinion of Oviedo, the sapodilla must be considered one of the best fruits of tropical America. It cannot vie, perhaps, with the pineapple or the cherimoya, but it is deservedly held in great esteem by the inhabitants of many tropical countries.
The tree is evergreen and stately, sometimes attaining a height of 50 to 75 feet, with a dense rounded or conical crown.
The wood is hard and durable; in fact, lintels believed to be made from it are found in the ruins of Tikal (Central America), dated 22.214.171.124.0 (Maya chronology) or 470 a.d. The branches often extend from the trunk horizontally. They are tough and pliable, which makes the sapodilla more resistant to cyclones and hurricanes than many other tropical fruit-trees. The bark contains a milky latex known commercially as chicle. This product is secured by tapping the trunk, and is exported in large quantities from southern Mexico and Central America to the United States, where it is used as the basis of chewing-gum. The leaves are entire or emarginate, ovate-elliptic to elliptic-lanceolate in outline, thick, stiff, shining, and 2 to 5 inches long. The small flowers are produced in the leaf-axils toward the ends of the branchlets; the calyx is composed of six small, ovate sepals, and the corolla is white, tubular, lobu-late, with six stamens opposite the lobules. The ovary is ten- to twelve-celled, each cell containing one ovule. The fruit is variable in form, but commonly is round, oval, or conical, and 2 to 3 1/2 inches in diameter. The thin skin is rusty brown and somewhat scurfy, giving the fruit a striking resemblance to an Irish potato. The flesh in the ripe fruit is yellow-brown, translucent, soft, sweet, and delicious, but when immature it contains tannin and a milky latex, so that it must not be eaten until fully ripe. The flavor has been likened to that of pears and brown sugar together; it is rich, slightly fragrant, and very pleasing to those who like sweet fruits. The seeds vary from none to ten or twelve and are hard, black, shining, obovate, flattened, and about 3/4 inch long. They are easily separated from the flesh and give little trouble in eating the fruit.
The sapodilla is native to tropical America. Henry Pittier considers it indigenous in Mexico south of the Isthmus of Tehuantepec, in Guatemala, and possibly in Salvador and northern Honduras. It is particularly abundant in the lowlands of Tabasco, Chiapas, and the western part of Yucatan, throughout which region the wild trees are tapped for chicle gum. From its native home it has been carried around the world. It is grown on the western coast of India and in Bengal, and, according to H. F. Macmillan, was introduced into Ceylon about 1802, but it has not become widely cultivated in that island. One meets with the tree in some parts of Africa, and Gerrit P. Wilder says it is common in the Hawaiian Islands. Throughout tropical America, it is abundant from southern Brazil to Florida.
In California the sapodilla has not been a success. Occasional trees in favored locations have lived for several years, but they have never reached the fruiting stage. Frosts have eventually killed most of them, and even the coolness of California nights has proved unfavorable to their natural development. In Florida the plant's cultivation is limited to the east coast from Palm Beach (or perhaps farther north) southward to Key West, and on the west coast as far north as the Manatee River. Mature trees in that state have passed uninjured through temperatures of 28° above zero, according to P. W. Reasoner. On the Florida Keys the sapodilla is one of the favorite fruits.
The common name sapodilla, by which the fruit is known in Florida, is taken from the Spanish zapotillo, meaning small zapote. In Mexico the usual name is chicozapote (often abbreviated to chico); this is derived from the Nahuatl tzicozapotl, or gum zapotl. In Mexico and other Spanish-speaking countries it is also called nispero, a name which properly belongs to the European medlar, Mespilus germanica. The English have formed from this the term naseberry, which is current in the West Indies and India. In the latter country it is called in Marathi chiku. The Maya name yd is used in Yucatan. In southern Brazil one form of the fruit is called sapoti, another sapota, while at Para the name is sapotilha. In German it is called breiapfel, and in French sapotille. The botanical synonymy is rather extensive: Achras Sapota, L., Sapota Achras, Mill., and Sapota zapotilla, Coville, are sometimes used.
The sapodilla is preeminently a dessert fruit. Rarely is it cooked or preserved in any way, although in Cuba and Brazil it is often made into a sherbet. According to Carl Wehmer 1 it contains about 14 per cent of sugar, of which 7.02 is saccharose, 3.7 dextrose, and 3.4 levulose. It also contains a small amount of acid and about 1 per cent of ash.
Although tropical in character, the sapodilla does not require a high degree of humidity nor entire freedom from frost. If liberally irrigated it can be grown in regions where the atmospheric humidity is low. The plant while young is injured by temperatures below freezing, but when mature it withstands 27° or 28° above zero. Although it prefers a rich sandy loam, it thrives on light clay and also on the shallow sandy soil underlaid with soft limestone which is found on the lower east coast of Florida. Indeed, its aptitude for rocky and forbidding situations on the Florida Keys is remarkable. It is said to grow well in India both on red sandy soil along the seashore and in the black alluvial land of the Dekkan.
It is the custom in India to plant sapodilla trees 15 to 20 feet apart. This is too close for the best results, particularly if the soil is rich and deep so that the tree grows to large size; 30 feet apart is probably close enough on good soils. V. N. Gokhale, writing in the Poona Agriculture College Magazine (1911), reports that in India the young plants are set in pits 1 foot wide and 2 to 3 feet deep in which a quantity of sheep-manure has been mixed with the soil, and that the mature trees are regularly supplied with manure two or three times a year.
Little attention has yet been given to pruning. Since the tree is of slow compact growth, it will probably require nothing more than the removal of an occasional unshapely branch. In southern Florida it thrives under the same cultural attention as citrus fruits.
1 Die Pflanzenstoffe.
The sapodilla is usually propagated by seed, but the variation among seedlings in productiveness as well as in quality, size, and shape of fruit necessitates some asexual means of propagation if the most desirable forms are to be perpetuated. Edward Simmonds has shown in Florida that the species can be budded in the same manner as the mango. Grafting and layering have been practiced in India.
Seeds, if kept dry, will retain their viability for several years. They should be sown in flats of light sandy soil, and covered to the depth of 1/2 inch. In warm weather germination takes place within a month. The young seedlings, after they have made their second leaves, may be potted off and carried along thus for a year or two, when they will be large enough to be set out in the open ground. Their growth is slow. If they are to be budded they should be planted in nursery rows which are 3 feet apart, and 18 inches apart in the row. In southern Florida, May has proved to be a good month for budding; in strictly tropical regions it can probably be done at any time of the year, provided the stock-plants are in active growth. Bud wood should be chosen from young branchlets which have begun to lose their greenish color and assume a brownish tinge. It should be examined carefully to ascertain that the axillary buds or "eyes" are well developed. Shield-budding is the method employed, the details being practically the same as in budding the mango. After making the incision in the stock, the bud should be inserted promptly, since the latex soon collects around the wound and renders insertion difficult. Waxed tape should be used for wrapping. After three or four weeks, the stock may be headed back and the wrap loosened, leaving the eye exposed so that it may start into growth.
A. C. Hartless, superintendent of the Government Botanical Gardens at Saharanpur, India, has found that the sapodilla can be inarched and cleft-grafted on Mimusops Kauki, L. Propagated in this manner the tree is dwarfed and bears at an earlier age than when grown on its own roots; it is believed also to be more productive. V. N. Gokhale says that propagation in western India is by seeds and layering. Plants obtained from layers are believed to be more vigorous than those from seed. Eight to ten layers can be made each year from a bearing tree, choosing the branches close to the ground.
Seedling sapodillas rarely come into bearing until six to eight years of age, even when grown under favorable conditions. They usually fruit heavily, and often produce two crops a year, one being much lighter, however, than the other. Due to this habit, together with the natural variation in season among seedling trees, ripe sapodillas are to be found in the markets of tropical America almost throughout the year.
Experiments have shown that the fruit can be shipped successfully and with little care in packing. The skin is thin and delicate and the fully ripe fruit is injured very easily; but if picked while still hard or "tree ripe," it does not begin to soften for several days. Sapodillas have been shipped from the Florida Keys to New York, packed in tomato-crates which hold six small baskets, each basket carrying six good-sized fruits. For local consumption, or for shipping short distances, the common procedure in Florida is to pull the fruits from the trees and simply throw them into boxes or baskets, in which they are carried to market, the ripe ones being picked out daily.
The fruit-flies (Trypetidse) are serious pests of the sapodilla in some regions, their larvae infesting the ripe fruit and rendering it unfit for consumption. Ceratitis capitata, Wied., the Mediterranean fruit-fly, and Anastrepha ludens, Loew., the Mexican fruit-fly, are two of the most troublesome species. The tree is attacked by very few insect or fungous enemies.
Seedlings differ in productiveness, ripening season, and in size, shape, and character of their fruits. Those which are unusually choice or valuable should be propagated by budding, grafting, or layering, and established as named varieties. Occasionally a seedless kind is found, or one whose fruits are very large, weighing a pound or even more. Differences in flavor and quality of fruit are also noticeable. There are not as yet any named varieties known in the trade.