v HAWAII AGRICULTURAL EXPERIMENT STATION HONOLULU, HAWAII Under the supervision of the UNITED STATES DEPARTMENT OF AGRICULTURE BULLETIN No. 55 Washington, I). C. November, 1926 BANANA CULTURE IN hawji!(Mt^!J By W. T. Pope, Horticulturist CONTENTS History and distribution Nomenclature Characters Composition and food value. Propagation Page 1 2 3 8 12 U.S. DEPOSI1QBY Cultural requirements — T3" Harvesting and shipping 19 Enemies 21 Description of varieties 24 Literature cited 47 Banana culture in the Hawaiian Islands has received much atten- tion since the establishment of the Hawaii Experiment Station in 1901, and especially since the close of the World War, when interest in the crop increased. Banana production now ranks third in im- portance of the local agricultural industries, and the fruit surpasses all other food crops in yield per acre. The Territory has a dozen banana varieties of commercial value, four of which are known to export trade, and several others have commercial possibilities. This bulletin directs attention to the comparatively easy culture of the banana in Hawaii, where large areas can be brought into fruit production in a short time. The plant has few enemies such as insect pests and diseases and is seldom damaged by the wind, and demand for the fruit is growing on the markets of the mainland. Local demands for fruit of a higher grade also are increasing. The banana is. for these reasons, deserving of greater scientific study than it has yet received. HISTORY AND DISTRIBUTION The origin of the banana and the story of its development through the centuries is of considerable importance to modern agricultural science. The plant is believed to be indigenous to the warm, moist regions of southern Asia, and was found in cultivation in vast areas in the valley of the Indus as early as 3*27 B. C. by the army of Alexander the Great. Bas-reliefs on the monuments of ancient Assyria and Egypt indicate its early culture, and recent investiga- tions regarding its early history and morphological development show that it was one of the first foods of man and also one of the earliest plants to be cultivated by him. Eraser (12) 1 states that 2 Reference is made by number (italic) to Literature cited, p. 17. 11SG2°— 20 1 1 2 BULLETIN 55, HAWAII EXPERIMENT STATION early inhabitants of the East believed that the banana plant was the source of good and evil and that the serpent which tempted Eve hid in a bunch of the fruit. Undoubtedly this legend influenced the early classifiers who designated two species of the plant as Musa paradisiaca (Fruit of Paradise) and M. sapientum (Fruit of Knowledge). The banana is widely scattered over the tropical world and is most successfully cultivated in a hot, damp climate. In many countries it is as important to the inhabitants as are grain plants to those living in cooler regions. The northern limit of cultivation, usually of the Cavendish variety, is reached in Florida south of 29° latitude, in the Canary Islands, and in Egypt; the southern limit in South Brazil, Natal, East Africa, and in the southern part of Queensland, Australia. The term " Hawaiian bananas " includes a number of varieties in use by the natives when the islands became known to Europeans following the discovery by Captain Cook in 1778. As a result of the study of the people and flora of the Hawaiian Islands it is thought that the banana was dispersed among the Pacific Islands by the Polynesians in their migrations, as the bulblike rhizomes, when partly dry, prove admirably adapted to long distance transportation, and varieties found growing in these islands exist in other island groups of the tropical Pacific. The Maoli group of bananas, for example, is in many respects very similar to that known by the same name in other islands of the south and central Pacific. There are also related varieties of both the Hawaiian Iholena and Popoulu groups. The Mai a hapai banana of Hawaii has the unusual habit of maturing its fruit within the trunk (IS, p. 53), which is characteristic of a variety in Java. The Hawaiian varieties are practically all of the starchy plantainlike kind — most palatable when they are cooked — and their botanical characters are more like those of varieties of the species sapientum than of the species paradisiaca, to which the plan- tain is usually assigned. The Polynesians fully appreciate the importance of establishing these seedless food plants where neither drought nor flood can exter- minate them. The corms are planted in the higher mountain gorges where they are insured against lack of moisture, and freshets aid in distributing certain of the rootstocks and suckers throughout the valleys below. The response which most of these varieties make to cultivation gives evidence that they are highly developed fruit plants which once were adapted to cultivation, but in recent times have lapsed into a semiwild condition. NOMENCLATURE The common name " banana " was adopted from the language of an African Kongo tribe, and first came into use during the sixteenth century. Prior to that time the fruit was called " apple of Paradise " and "Adam's fig." The name " banana " seems to have been borne for a long period by the fruit which was eaten raw. The term '* plantain " was given to a variety which, though closely related to the banana, is edible only after being cooked. Both these fruits belong to the genus Musa of the Musacese or Banana family, natural order Scitaminacese. The botanist Linnaeus (1707-1778) gave the BANANA CULTURE IN HAWAII 6 generic name Musa to the banana group in honor of Antonius Musa, a learned physician of the early Roman Empire. Notwithstanding the fact that the banana was an important agri- cultural crop even before the time of written records, its specific and varietal relations have never been well defined. About 1750 an attempt was made to establish several of the leading species. The name sapientum (affording wisdom) was given to the banana and that of paradisiaca (pertaining to Paradise) to the plantain to differentiate the species of the genus Musa. Later, the name caven- dishii was given to another species of the banana. Other species have since been added and hundreds of so-called varieties brought into cultivation, but few have been completely described. Quisum- bing (7-5, p. 10) states that 77 species have been described. In the work of Baker (£, p. 205) three subdivisions of the genus Musa were made: Eumusa, Rhodochlamys. and Physocaulis. The subdivisions are based on well differentiated characters, mainly pertaining to the floral parts, and are described in detail by Fawcett (11, p. 263), and in the Kew Bulletin for 1894 (1). What determines the difference between bananas and plantains is a problem under the present method of classification. Some botanists are of the opinion that the species sapientum and paradisiaca are the same, with very marked variations, whereas others believe that the former is a subspecies of the latter. Schumann (18, p. 19) places sapientum as a subspecies of paradisiaca. The proper use of the terms " plantain " and " banana," or the specific names sapi- entum and paradisiaca is uncertain, because of the lack of uniform nomenclature for the different forms. A variety has a different name in almost every country where it is grown, the standard com- mercial varieties of American trade proving no exception. The most widely grown commercial variety, for example, is known in different places as Martinique, Jamaica, Gros Michel, and Bluefields. The leading commercial banana of Hawaii is also known by such names as Cavendish, Dwarf, Governor, and Chinese. The native varieties also often have different names in different parts of the same island. In most banana-growing countries a variety may be known by different names in the same locality. Some varieties make a much greater vegetative growth in one localit}^ than in another, and may derive their names from the nature of their growth. In Hawaii several other genera of plants which are closely related to the genus Musa include the Canna, Ravenala, Streiitzia, and Heliconia. CHARACTERS A thorough knowledge of the characters of the banana plant is essential to those seriously attempting its culture. The seedless varieties, by reason of their easy culture, high food value, and immense yields, have become well established, whereas the function of the flower and the possibility of creating new varieties through seed production have not received the attention they deserve. HABITS OF GROWTH The banana plant, as commonly understood, is a tropical herba- ceous perennial which assumes treelike proportions, some of the larger species often reaching 30 or more feet high. The parts of the plant, 4 BULLETIN 55, HAWAII EXPERIMENT STATION though somewhat fibrous, are coarse in structure and often contain as much as 85 per cent water (16, p. IT). The trunk and large leaves present an ornamental appearance and the flowers and fruit par- ticularly are interesting botanically. ROOTS The root system consists of two sets of roots, the horizontal and the vertical ; the former, which is the superior, radiates from around the bulb, whereas the latter extends downward from the base. The main roots are tough and cordlike and of nearly uniform thickness throughout, possessing numerous short, threadlike secondary roots or rootlets growing out at right angles. Both main and secondary roots bear numerous root hairs, or feeders, which absorb liquid plant food from the soil. The food passes along the fibrovascular system of cells of the roots, bulb, and stems, to the leaves. Investigation shows that the banana roots, unlike those of many other plants, can not adapt themselves to adverse conditions, such as sour or heavy soil. The distance to which they extend depends largely upon the nature of the soil. Under favorable conditions the horizontal roots may be found at a depth of 6 inches to 2 feet, and the vertical roots 6 inches to 6 feet, both growing at the rate of 2 feet per month. STEM The true stem is the underground " bulb," morphologically known as a tuberous rhizome, wherein is stored the starchy plant food used in connection with the central bud, root, and sucker-bud-producing tissue. The suckers rise from this tissue as additional trunks of the plant group. The trunk consists of a cylinder composed of coarsely constructed concentric layers, each of which is the base of a leaf- stalk. Combined, these layers protect the younger leaves and the flowering stalk. The plant food is used chiefly in the production of suckers and the growth of the fruit. The production of too many suckers results in poorly developed fruit. A sucker may be consid- ered a plant when it has developed to a size with sufficient roots to maintain its own growth fully. LEAVES The leaves of the banana plant, consisting of leafstalk and blade, vary in number from 8 to 20 or more, depending upon the vigor of the plant. Normally, they are 8 to 12 feet long and 2 feet or more wide. Prior to expanding, the young leaf is cylindrically rolled on itself, being closed at the tip, possibly to prevent water from entering the center of the trunk where the blossom bud is forming. The exposed portion of the petiole or leafstalk, which varies from one to several feet long, is almost cylindrical, its raised edges forming a distinct trough above. The leaves are so arranged as to adapt them- selves to weather conditions. When the sun's rays are perpendicular and too intense, the blade collapses, the under surfaces containing the pores (stomata) coming together and thus protecting the plant against too great evaporation. In wet and moderately cool weather when growing conditions are very favorable the edges of the blade curve upward, permitting increased evaporation, which is necessary 1 Bui. 55, Hawaii Agr. Expt. Station Plate 1 _ m 2 5~ m A.— The flowers of the Chamaluco variety are typical in form of parts of those of most varieties of seedless bananas. (1) Pistillate flower: a, perianth, b, petal of corolla, c, rudimentary stamens, d, style of pistil, e, stigma, /, ovary which becomes fruit; (2) neutral flower; (3) staminate flower: c\ Stamen with anther, /', rudimentary ovary B.— The characters of the flowers of different varieties of bananas are of importance in their identification. Staminate flowers, reading from left to right: Top 'row, 'Apple, Abaca, Bra- zilian, Chamaluco, and Borabora; lower row, Father Leonore, ilamakua, Iholena, Largo, and Dwarf Plantain Bui. 55, Hawaii Agr. Expt. Station PLATE 2 BANANA CULTURE IN HAWAII 5 for rapid growth. The crude plant food which has been absorbed by the roots and carried up the. ..stem is transformed in the leaf, Whence it is distributed where needed to build plant tissue. FLOWERS The following is a brief description of the floral parts: The ovary, or basal part of the pistillate flower, later becomes the fruit. The ovaries of neutral and staminate flowers remain rudimentary and perish. The perianth, corresponding to the calyx of any typical, complete flower, is the protective covering of the more delicate, essential organs known as stamens and pistils. The corolla is much modified in the banana flower, usually being represented by a single free petal, with sometimes three petals, as in the Ice Cream variety and the common plantain. The petal usually holds the nectar surrounding the base of the style. Normally, there are six stamens, but in most seedless varieties only five, the sixth being very rudimentary, or wanting. The anthers, the extreme por- tions of normal stamens, contain the pollen. On reaching maturity they split lengthwise along the margin, exposing the inner surfaces and releasing pollen grains. The exposed surfaces gradually turn dark in a few hours after the flowers open. The portion of the pistil extending from the apex of the ovary consists of a slim style sur- mounted by a more or less globular stigma, the surface showing- evidence of several lobes, usually six in number. The inflorescence of the banana, which undoubtedly has under- gone many modifications since it first became known to man, is of much interest and importance. Its variations are numerous but of a constancy permitting their use as a most reliable basis for systemati- cally distinguishing the varieties. 2 The flowering stalk grows up through the center of the trunk, appearing under normal conditions at the top in the form of a large bud when the trunk is about 9 or 10 months old. The flower bud develops rapidly, and, as it increases in size its weight causes it to hang pendant from the plant. 3 Botanically, the inflorescence is of the monoecious type, the flowers in most species and varieties being pistillate, neutral, or staminate. the last two kinds closely resembling one another (pi. 1, A). The flowers are spirally arranged on the flower stalk in consecutive clusters extending from the base to the apex. One or two of the clusters open at a time. Usually the pistillate flowers open in four to seven days. Each developing cluster, consisting of two trans- verse rows having few to 20 or more flowers, depending upon the variety and conditions of growth, is completely protected by a thick, close-fitting, leaflike bract varying in shape and color with the dif- ferent species and varieties. In color the outward surface of the bracts may be purple, claret, or reddish-brown, powdered with a frostlike bloom, and the inner surface may be red, pink, purple, vio- - Flowers should be chosen for study when they have reached a certain definite point of growth. Pistillate flowers, for example, should be examined aboul the time the last cluster is opening; ;i day or two later the neutral flowers nay be Been; and two days later still the staminate flowers will have developed. ■In The Kusaie and Fei varieties tin- scape with inflorescence remains erect. A strain of the Cavendish banana produces two or more flowering stalks within a single trunk, whereas the native Hawaiian variety Mahoe produces a single flower stalk which divides midway of the cluster and bears twin bunches of fruit (pi. 2, A). 6 BULLETIN 55, HAWAII EXPERIMENT STATION let, yellow, orange, brown, or a blend of several of these colors, which are well displayed when the bract is raised as it rolls back at the top. About this time the flowers beneath the bracts may be visited by in- sects in search of nectar. After completing its work of protecting and displaying the flowers, each bract falls. In the Chinese or Cavendish variety the bracts covering the staminate flowers are persistent (pi. 2, B). The pistillate flowers are the most important of the several kinds forming the inflorescence, particularly the ovaries, which eventually become the fruit. The number of clusters under favorable conditions varies from six to nine or even more, some varieties producing a greater number than others. The ovary is about two-thirds the length of the pistillate flower, and has three seed compartments with many well-distributed ovules, which in the seedless banana remain small and imperfect. The apex of the ovary supports the other floral parts, including the central style, which is surmounted with a plump, six-lobed stigma and surrounded by a whorl of five short, im- perfect stamens. 4 The floral envelope is considerably modified. The outer and longer portion is the perianth, and is said to consist of three sepals and two rudimentary petals all united, but indicated by the five lobes at the end. The third and separate petal representing the corolla is short, wide, deeply cupped on the inner side, and lipped at the edges. In color these floral parts may be pale cream, yellow, red, or streaked, depending upon the variety. The cups of the petals of the three kinds of flowers secrete a clear, viscid nectar of sweet, pleasant flavor. In the Iholena group the nectar has the consistency of jelly, which was a delicacy eagerly sought by the early Hawaiians. In the neutral flowers the stamens and pistils are usually unde- veloped, and the ovary is half the length of the flower. Fertile pollen grains are rarely found in the stamens, and only few varieties in Hawaii, such as the Bluefields and Lady Finger, have neutral flowered ovaries developing into fruits. The male or staminate flowers are arranged in clusters more at the end of the inflorescence. Each flower normally possesses live prom- inent stamens, usually extending beyond the other parts (pi. 1, B). The anthers, or pollen sacks, are long and marked in color, but in most varieties possess no pollen. However, abundance of pollen was found by the writer in the anthers of staminate flowers of the vari- eties Bluefields, Popoulu, Iholena, Lele, Kapua, abaca, Borabora, and Maia Oa. Pollen grains collected from well-developed stamens of pistillate flowers of the last three-mentioned varieties and ex- amined under a compound microscope were found to be spherical in shape and white or yellowish in color. The grains are connected in chains until fairly mature, when they split apart. The pistil is short and undeveloped. The ovary is only about one-third the length of the flower. Usually the perianth and the corolla petal are more highly colored than other parts of the flower, and, like the same organs in the pistillate flower, have colors peculiar to the variety. 4 In some species the stamens are perfect, and occasionally a sixth stamen is present. BANANA CULTURE IX HAWAII 7 Like a number of other fruits of commercial importance, the seedless banana is distinctly parthenocarpic and does not require the stimulus of pollination to insure the setting of fruit (#, p. 293). However. 15 of the :i7 species of the subgenus Eumusa produce fruit containing seeds [11. p. 263). A number of well-established vari- eties of seedless bananas, including Gros Michel (Bluefields) and Apple, have been successfully pollinated by hand and caused to produce seed (1L preface, p. 8). The Ice Cream variety of Hawaii when growing near abaca plants is occasionally naturally pollinated and produces seed. W. J. MacNeil, Oahu College, Honolulu, reports that in 1909 he succeeded in crossing flowers of the Ice Cream vari- ety with pollen from seed-producing banana, presumably abaca. More than one bunch produced seeds, some fruits having 1 to 15. Ten of the seeds, collected at random when dry. weighed 0.6 gram, and were 0.8 by 0.6 by 0.4 to 0.6 by 0.5 by 0.1 centimeter in dimen- sions. Of 50 seeds planted on two different occasions none germi- nated. In nearly all commercial varieties the pistillate flowers with im- perfect stamens are open and their stigmas past the receptive stage for pollen before either the neutral or the st animate flowers are released by the opening of the bracts (pi. 3, A). This fact indicates the need of cross pollination to produce seed. Insects, which are attracted to the flowers by the nectar, might possibly be the occasion of cross pollination, but since seeds are rarely produced, the pollen of most of the commercial varieties either does not develop, or it is infertile. It is believed that the original wild banana bore perfect flowers; that is, having both stamens and pistils, as is still represented in some of the local varieties, and that pollination of flowers of the same cluster was aided by external agencies, such as the wind and insects. In isolated specimens of the local Borabora (pi. 3, B), Maia Oa. and abaca varieties, it was observed that the flowers becoming seed- bearing fruits were pollinated before the staminate flowers, located farther along the rachis, were released from under the bracts. It is also probable that there once were species, if not varieties, whose floral parts were modified, requiring cross pollination to fertilize the ovules and produce seeds capable of germination, just as is now the ca-e with most of the Hawaiian commercial varieties, which usually are parthenocarpic. Examination of a number of these varieties failed to show the presence of pollen on their flowers. Several varieties, such as the Ice Cream and Chamaluco, had some pollen, the surface of whose grains was found to be collapsed, however, sug- gesting infertility. S. C. Harland. of Trinidad, British West Indies, reports crossing successfully the Gros Michel, resulting in the produc- tion of seeds which germinated, giving in one instance a hybrid of highly desirable qualities. Some varieties are known to be bud sports; for example, the Green Red banana of Panama, which O. A. Reinking. pathologist of the United Fruit Co.. states is a bud sport of the well-known Red variety, i- also a bud -port of some yellow variety. A bunch of the fruit of the Green Red banana was found to contain 150 seeds scattered throughout the linger-, only about half a dozen of which were perfect. Doctor Reinking call- attention to 8 BULLETIN 55, HAWAII EXPERIMENT STATION the Burrow Apple plantain as a variety of the species paradisiaca producing seed, a portion of which have been germinated and successfullv grown. FRUIT The fruit of the banana is borne in a bunch consisting of a number of clusters called " hands," which are further developments of the floral panicle. The hands, bearing 5 to 20 or more bananas arranged in two rows, commonly called " fingers," grow separately in spiral ar- rangement on the axis of the rachis, called the stem. The bunch is the commercial unit where bananas are sold wholesale, and is classed as ranging from 6 to 9 hands. Smaller bunches are not readily mar- keted. Standard bunches have 9 hands and weigh from 50 to 80 pounds, varying with the variety and conditions under which pro- duced. Cavendish bananas given good culture may average 85 pounds in w r eight, and rarely 100 pounds per bunch. Large bunches of Bluefields often weigh 100 pounds or more, and occasionally bunches weighing 150 pounds, with 20 or more hands and over 300 fruits, have been exhibited. One bunch shown at the Territorial Fair of Hawaii, 1924, weighed over 170 pounds. The favorite variety of the Hawaiians, Moa, which grows wild in the deep moun- tain valleys, often has less than a dozen fruits to the entire bunch. Given special care, however, this variety can be made to produce a larger number. In Cochin China, the " Lubang " variety (Musa corniculata) produces only one fruit which has the appearance of a large cucumber. The Lady Finger, a commercial banana of the West Indies and now under trial at the station, produces as many as 300 to 400 fruits to the bunch. The Guindy, said to be the best banana of India, often has 1,000 fruits to the bunch (77, p. 181). The King of Thousands, a variety of banana of the Malay Archi- pelago, is said to produce bunches of great size. A bunch measuring 7 feet long and bearing 2,000 fruits was produced in a Singapore garden in 1911 (0, p. 452). The fruit develops in 60 to 80 days after the inflorescence has pushed out of the crown of the trunk. Fruit development, like the growth of the rest of the plant, may be greatly retarded by adverse conditions. Individual fruits of the edible banana vary greatly in size, shape, color, and flavor, according to the variety and cultural conditions. The general description of the fruit of the seedless banana is as fol- lows : Weight, 2 to 16 ounces; length, 1 to 18 inches; shape, elon- gated, cylindrical, sometimes angular, somewhat curved; skin, thin and tender to tough and leathery; color of skin, yellow or red at maturity, and in some varieties, green when ripe; pulp, yellow, pink, salmon, or white in color, soft to firm in consistency; flavor, usually pleasing when the fruit is ripe. 5 COMPOSITION AND FOOD VALUE The composition and food value of the banana are of interest to the grower and to the consumer. From the composition the grower B The fruit should be studied first while it is 1 green but at full size, and later when it fully ripens. Bui. 55. Hawaii Agr. Expt. Station Plate 3 Bui. 55, Hawaii Agr. Expt. Station Plate 4 BANANA CTI.TURE IN HAWAII 9 learns the importance of his crop as a food, and the demands the plant makes upon the soil medium he is to provide; the consumer learns the food value of the fruit, and the dietitian its proper place in the dietary. Analyses of a number of locally grown bananas, made with a slight modification of the method recommended by the Association of Official Agricultural Chemists (#0, p. 77) and published by the station in 1914 (10, p. GG). indicate little difference in composition between them and bananas grown elsewhere. Bananas have a high and variable sugar content, the highest being in the Hawaiian cook- ing, or so-called native, bananas (pi. 4, A). The green fruit of any variety of bananas, such as that used for dehydration in the manu- facture of flour, has a starch content of about 12 per cent, most of which disappears during ripening, along with the tannic or organic acids. Doherty (9, p. 187) reports G per cent of starch remaining in some ripe fruit, and other observers have found less. A test for tannin on cross sections of both the green and ripe fruit showed tannin to be arranged in a narrow line around the outer margin of the fruit and along the three divisions of the core radiating from the center. Eicciardi (17, p. 554) explains that tannin, together with organic acids, like much of the starch, disappears during the process of ripen- ing. Thoroughly ripened fresh fruit is for this reason more easily digested than unripe fruit. The proteins, consisting of albumen and gluten, are small in amount, constituting little over 1 per cent of the edible portion of the ripe fruit. Acidity averages about 0.329 per cent, but runs unusually high (over 0.4 per cent) in the Apple and Brazilian varieties. A similar variation is noted in the different varieties in fat content, in which the cooking banana is unusually high. Table 1 gives the results of analyses of different kinds of bananas. Table 1. — Composition of different kinds of banana fruits Kind Chinese Apple Brazilian Baking (Hawaiian) Fehi Carbohydrates Edible Waste Water Protein Acids Fat as H 2 SO< Sugar Crude fiber 1 i Per cent Per cent Per cent Per cent Per cent Per cent Per cent Per cent 70. 00 30. 00 78.72 1.788 0. 180 0. 245 16.66 0.253 74.49 25.51 68.48 1.238 .223 .417 24.15 .351 68.25 31. 75 72.22 1. 775 . 201 . 406 19.68 .305 75.72 24.28 67.78 1.350 . 518 . 397 26.20 .333 64.29 35.71 72. 13 1.069 .046 .230 » 14. 49 .594 Ash Per cent 0.955 .964 .924 .750 Determined by copper reduction method. The banana leads all other raw fruits in food value and surpasses most of the vegetables in energy value and tissue-building elements. According to S. C. Prescott. of the Massachusetts Institute of Tech- nology, it provides more actual food for the same cost than any other fresh fruit or vegetable, fish, meat, milk, or eggs (16, p. 53). Table 2 compares the nutritive value of the banana with that of some other commonly used Hawaiian fruits. 11862°— 20 2 10 BULLETIN 55, HAWAII EXPERIMENT STATION Table 2. — Comparison of composition of bananas and other fruits Edible portion Waste Water Protein Fat Carbohydrates Acids Kind as H2S0 < i Sugar Crude fiber Ash Banana (Chinese) Mango (Pirie) Avocado (Esbank) __ Per cent 70.00 60.00 Per cent 30.00 40.00 Per cent 78.73 79.48 81.76 53. 18 83.73 87.85 Per cent 1.788 .456 .950 1.575 .548 .681 .375 .400 Per cent 0.180 .032 12. 620 .190 .148 .387 "\~500~ Per cent Per cent 0.245 | 16.66 .221 | 14.78 2.84 -. 049 9. 49 . 140 ! 13. 76 . 882 5. 90 . 660 1 10. 70 ■ 14.20 Per cent 0.253 .508 1.030 1.204 .827 .575 Per cent 0.955 .343 .800 .952 .687 .453 Breadfruit (Hawaiian) Papaya (No. 4610) 77. 75 22.25 Orange (Kona) Pineapple. _ . ... 72. 13 27.87 Apple ... ... 84.60 .300 The world's leading food crops, including wheat, rice, corn, and potatoes, have become great staples because of their large yields of energy-producing food in concentrated and palatable form. In a comparative study of these foods, the banana has been found to lead in total production per acre and in fuel value per acre. Table 3 compares the acre yield and fuel value of a fair crop of Chinese bananas and the other staple crops. Table 3. — Yield and food value of bananas and other crops 1 Kind of crop Fair yield per acre Fuel value per pound Fuel value per acre Bananas.. .... . . ... .... . _ Pounds 32, 000 1,620 3,000 2,240 10, 170 14, 000 Calories 260 1,650 1,620 1,635 295 440 Calories 8, 320, 000 Wheat •_ 2, 673, 000 Rice ... ... ._ .. __ .. . 4, 860, 000 Corn. ---. .. . .......... . 3, 662, 000 White potatoes. __ ______________________ ' 3, 000, 150 Sweet potatoes ... ._ _ _ _ _ ._ _. 6, 160, 000 Hawaii Exp. Sta. Ext. Bui. 6 (1917), p. 4. The yields of bananas, rice, and sweet potatoes given in the table are, as explained by Higgins, based upon the experience of a num- ber of growers in Hawaii, and the estimate of fair yields of the other crops was arrived at by increasing by 50 per cent the average yields of plants in the areas of the United States where they are grown ex- tensively. Average yields can not be considered fair yields, but in- creasing them by 50 per cent would seem to be fair to these crops when comparing them with bananas. The estimated yield for rice includes the two crops which are harvested each year in Hawaii. Locally grown sugar will probably exceed the other crops in caloric value, but it can be used only in limited quantity in the diet. Ba- nanas as fresh fruit are too bulky to form a satisfactory ration, for one must consume 1,400 grams, or approximately 50 ounces, of the fruit to obtain 300 grams of carbohydrate. Reduced to a concentrated form, as by drying or converting into flour, the banana can be used in very large quantities and in times of necessity could replace much of the wheat, corn, potatoes, and similar imports. In these prepared forms the banana is adapted to a much wider use, and its nutritive value compares more favorably with the manufactured products of the cereals and dehydrated fruits. BANANA CULTURE IN HAWAII 11 BANANA FLOUR Both the banana and the plantain form a far more important article of food in some other countries than they do in Hawaii or in any of the United States. Fawcett (11. p. 119) states that they take the place of wheat, rye. barley, and potatoes for an immense portion of the human race. Flour is the most concentrated form to which the banana can be reduced, and is manufactured from fully grown green specimens which have not begun to ripen. In the West Indies the fruit is cut from the bunches and placed in water at about 176° F. for four or five minutes so that the green skin may the more easily be removed. The pulp is then split in halves with a wooden, bone, or silver blade. After the banana has been thus prepared, drying, either by sun or artificial heat, takes place rapidly. AVhen the mois- ture has been reduced to 15 per cent or less, the dried fruit is ground and run through sieves having 120 meshes to the inch. The freshly prepared product has an odor characteristic of the fresh article, and an agreeable and somewhat sweet taste. It may be stored in boxes or barrels lined with paper. Some difficulty has been encountered in making bread with banana flour alone, but when mixed with wheat flour or with oatmeal it proves satisfactory. Good bread has been made from banana flour paste which had been subjected to the action of steam under pressure. Table 4 compares the nutritive value of banana flour and other foods. Table 4. — Comparative nutritive value of banana and other foods 1 Kind of food Moisture Protefn Fat Carbo- hydrates Ash Food value per pound Per cent 75.3 9.7 Per cent 1.3 3.1 11.4 9.2 2.2 Per cent 0.6 .5 1.0 1.9 .1 Per cent 22.0 84.1 75.1 75.4 18.4 Per cent 0.8 2.6 .5 1.0 1.0 Calories 460 1,610 Wheat flour _ . ... _ . 12.0 12.5 78.3 1,650 1,655 Potato (white).. . . 385 i Hawaii Exp. Sta. Ext. Bui. 6 (1917), p. 7. DRIED BANANAS Bananas may be preserved in a concentrated form known as banana "figs," which are simply the dried ripe fruit. Drying as a means of preserving the banana is commonly practiced in theWest Indies and many other countries. Trials of different methods of processing by the station indicate that drying is applicable to Hawaiian-grown varieties, and fig making from the banana seems possible. The following is a simple method of preserving the banana : The firm, ripe fruit, peeled and split lengthwise in halves or fourths, is placed on trays and dried, either in the sun or with arti- ficial heat. Various kinds of driers, including evaporators and vacuum driers, are used. The drying process is complete when the dried product resembles dried figs, prunes, or dates. In drying, the fruit becomes covered wtih a white, sugary powder formed from its own juice. In the ripe fruit the starch turns to sugar, which in the drying process acts as a preservative and enables the fruit to keep 12 BULLETIN 55, HAWAII EXPERIMENT STATION for a considerable time. That the dried fruit compares favorably with other dried fruits is shown in Table 5. Table 5. — Average composition of dried bananas and other dried fruits * Kind of fruit Refuse Water Protein Fat Carbo- hydrates Ash Fuel value per pound Per cent Per cent 29.2 15.4 18.8 14.6 26.1 29.4 Per cent 5.3 2.1 4.3 2.6 1.6 4.7 Per cent 2.3 2.8 .3 3.3 2.2 1.0 Per cent 57.9 78.4 74.2 76.1 68.1 62.5 Per cent 5.3 1.3 2.4 3.4 2.0 2.4 Calories 1,240 1 615 10.0 Figs 1,475 1,605 1,350 1,290 10.0 i U. S. Dept. Agr. Farmers' Bui. 293, p. 14. PROPAGATION Seedless bananas are propagated by asexual methods, three differ- ent parts of the stem being used: (1) Large suckers, 4 to 6 months old, having well-developed basal bulbs (pi. 4, B) ; (2) small suckers, a few weeks to 2 or 3 months old and 8 to 30 inches high; and (3) old stumps of plants that have fruited (pi. 5, A). Large suckers, 4 or 5 feet high, are the forms most commonly used to propagate the banana in Hawaii. The b'ulbs contain a large supply of concentrated food, have tissue ready for root development, and have started to take on the characters, of adult foliage. Care should be taken, however, to see that the flower cluster has not jet begun to form in the trunk. Large suckers should be carefully re- moved from the plant after the fully developed bunches of fruit have been severed. All fibrous roots should be removed, 'the ex- panded leaves cut back to prevent excessive transpiration, and the suckers allowed to dry for several days to heal the cut surfaces before planting. Some growers place the suckers in heaps 8 to 10 deep, cover them with trash to protect them from the rays of the sun, and allow them to remain for about a month. Large suckers have been found to be very satisfactory in local commercial plantings of the Cavendish and Brazilian varieties and to produce earlier and more desirable bunches of fruit than smaller suckers or heads. In some countries the large suckers are cut back to within a few inches of the solid corm or bulb, the central or heart bud is cut out, and all surface buds are removed, excepting one which then takes its strength from the parent bulb. When the heart bulb is not destroyed, a new bulb forms on the top of the old one, producing a plant which may be the more easily blown over. " Peepers," or small suckers less than two or three months old, should be handled with great care to guard against bruising, and should be allowed to dry for several days prior to planting, as a precaution against decay. Small suckers may not prove wholly satisfactory, but can be used in time of scarcity of propagating material. Old banana stumps are sometimes dug up and cut back to heads. They may be planted whole or in longitudinal sections, each of which should have one good bud (pi. 5, A). After the cut surfaces have Bui. 55. Hawaii Agr. Expt. Station Plate 5 A. — Propagating material of banana plants, (l) A medium-sized rhizome •"IilmI"; CI) a large head cut into sections, each having at least one evident bud; (3) small rhizomes which are used entire. The white arrow indicates the bud which develops into the sucker B. — Field of suckers of the Cavendish or Chinese variety set in the customary way for growing at lower levels where irrigation is necessary. The su-kers were BJ t in September, 1924, and photographed two weeks later. Note the arrangement of the trenches BAN" AX A CULTURE IX HAWAII 13 healed the stumps should be planted at least 8 inches deep, with the bud in an upright position. Stumps are said to be used in other countries where commercial varieties are grown on a large scale. CULTURAL REQUIREMENTS SOIL Practically all the agricultural soils of Hawaii may be made suit- able for banana growing. At the lower elevations, where most of the commercial varieties are grown, the soils are conglomerate de- posits formed from various decomposed lavas. 6 Productivity of these soils depends more upon their physical character than upon their chemical composition, although the latter must be given careful consideration. At elevations of 1,000 feet and higher, where the rainfall is sufficient for the production of natural forest growth, the soils consist of decomposed lavas with an abundance of humus. Such soils have excellent drainage on account of the porous nature of the lavas directly underlying them. Except for the clearing necessary, these forest lands are more easily brought into use, but, owing to their altitude, require a longer time to produce crops than the low-lying lands. They produce commercial bananas of excellent quality, and are well adapted to growing most of the native bananas. The virgin forest loam, where the rainfall is adequate, is the ideal soil for banana culture, but a great variety of soils may be success- fully used if their physical and chemical properties are improved by proper tillage, liberal applications of organic matter, and irriga- tion. Water-holding capacity and good drainage are among the essential requirements for banana growing. Moisture must be abun- dant at all times to insure good crop yields. It is estimated that the banana plant requires about 600 pounds of water for every pound of dry matter produced. PREPARATION Land at the lower elevations, where usually the forest growth is sparse, should first be cleared of all vegetation and stones. This may require some expense, but partial clearing preceding breaking the land is a doubtful economy. A well-cleared held means cheaper and better tillage. The banana lands at the lower elevations are largely sedimentary in formation, and rather firmly packed, re- quiring deep and thorough plowing. After weathering by exposure to air and sunshine the roughly plowed field should be harrowed and staked off for planting. The fields customarily are laid out with regularity in small areas of 5 or 10 acre blocks for conveniently carrying on the various necessary operations. The rows are laid out in ditches V/ 2 to 2 feet deep with high ridges between (pi. 5, B). The ditches are made by running a plow several times through each row, after which the loosened soil is thrown to the sides. If the subsoil is hard it should be broken up with a subsoil plow and the soil should be reduced to a fine state of tilth to furnish a suit- 6 In some localities the lava- are mixed with calcareous material consisting either of coral sand brought in from the seashore by the agency of the wind or partly decom- posed coral reefs that have arisen out of the 14 BULLETIN 55, HAWAII EXPERIMENT STATION able bed for the plants. Loosening the soil gives better drainage and a greater feeding area for the roots, which then become deeply established and enable the plant to withstand heavy winds. Thor- oughly preparing the land also greatly increases nitrification and other chemical processes releasing plant food in the soil. IMPROVING THE SOIL In addition to deep plowing and good drainage, banana soils often need some kind of fertilizer. Fertilizing materials include barnyard manures, green manures, lime, and chemical or commercial fertilizers. The soils usually have most of the necessary elements. Nitrogen, potassium, phosphorus, and calcium are the elements most likely to become exhausted and to require replacement by the use of fertilizers. Numerous experiments with fertilizers for bana- nas have been made by private growers, fertilizer concerns, and by the station, alone and in cooperation with growers. Barnyard manure has been found to be very beneficial, especially at the central station in Honolulu. In using fertilizers the grower must be guided not only by his general knowledge of the needs of the plant but also by close study of its growth, including its composition and the action of the soil under treatment. Considerable experience is required to determine the kind of fertilizer necessary and the best method of applying it. Sufficient nitrogen is shown in a vigorous growth of rich green fo- liage, whereas nitrogen deficiency is generally indicated by poor growth of foliage of yellowish color. Nitrogen deficiency is often corrected by the application of barnyard manure and the incorpora- tion of an abundance of humus in the soil, with more moisture. Green manures also assist in maintaining humus, which aids in nitri- fication. Nitrogen deficiency may be temporarily overcome by using nitrate of soda, sulphate of ammonia, or dried blood. Potash also often improves the fruiting quality of banana plants. Both Higgins and Fawcett state that where vigorous plants produce bunches of fruit of inferior size and quality the condition may often be cor- rected by using potash in some form, such as sulphate or muriate of potash. The need of phosphoric acid is probably not so easily determined, but the fact that phosphorus is present in practically every plant cell indicates its importance. Applied as superphos- phate, which is phosphate rock treated with sulphuric acid, phos- phoric acid is often believed to be the correcting element for stunted growth. Lime in excess of that already present in the soil may sometimes be required as a soil amendment, or, what is known as an indirect fertilizer, rendering the potash more available to the plant. It aids nitrification and may also correct soil acidity, result- ing in an improved physical condition. (For fuller discussion of the use of fertilizers, see 11, p. 69.) PLANTING DISTANCES The distance between the rows and the plants in the row varies somewhat with the character of the soil, the amount of moisture available, and the variety to be planted. Different distances are used in setting the Chinese banana, the leading commercial variety BANANA CULTURE IN HAWAII 15 in Hawaii. Success may be obtained by planting 6 by (>; 6 by 7, 7 by 7, 7 by 8, 8 by 9, and 8 by 10 feet; and greater distances are required for large plants, such as the Bluefields and Brazilian varieties. Large plants should be set at least 14 by 1-1 feet on land that is not very fertile, some growers preferring 15 by 15 and 16 by 16 feet. The greater distances permit the growing of a larger number of suckers and fruiting trunks in each clump at the same time. With the greater distances between plants the suckers should be set in large holes, the size of which will depend upon the prepara- tion previously given the soil. In poorly prepared soil the holes must be made very large, being at least 4 feet across and V/ 2 or 2 feet deep, depending upon the character of the subsoil. When the land has been thoroughly plowed and harrowed the holes can be made with a small amount of hand labor. Large suckers of the Chinese variety are set locally at selected distances in holes made in the bottom of the ditch with 5 or 6 inches of soil firmed around each plant. In dry weather the plantings should be watered as soon as the areas of acre-blocks are set. Table 6 gives the planting dis- tances and number of plants per acre. Table C>. — Planting distances and number of plants per acre 1 Distances (feet) 6bv6 6 by 7 7 by 7 7 by 8 8 by 9 Plants (number) 1,210 1,037 888 777 605 Distances (feet) 8 bv 10_ 14 by 14 15 by 15 16 by 16 Plants (number) 544 222 194 170 1 " To find the number of plants required to set an acre, multiply together two distances, in feet, at which the trees stand apart, and divide 43,560 by the product; the quotient will be the number of plants required." (5, pp. 117-119). CULTIVATION Tillage is one of the most important factors entering into the production of good bananas, and success depends to a considerable extent upon the thoroughness of preparation given the soil before planting. Most of the typical banana lands of Hawaii are kept free of weeds by some sort of shallow tillage which is maintained until the plants are large enough to shade the ground completely. The implement best suited to shallow tillage is an animal-drawn, double-shovel culti- vator which loosens the soil to a depth of 2 to 3 inches. Some growers prefer using a 6-inch stirring plow, which effectively loosen:] the soil to a depth of 4 to 6 inches. In cases where cultivators and plows can not well be used the work may be started with a spading fork and finished by hoeing. Cultivation is sometimes given after each rain or irrigation, and in other instances once in six or eight weeks. Only one cultivation a year is necessary after the plants become well established. In parts of the West Indies cover crops are grown during the wet season. A cover crop prevents surface washing, and when tinned under, enriches the soil and improves its texture. The Jerusalem pea (P/u/xeoIus trinervis) is most commonly used, as it makes a fairly dense growth in the shade of the banana plants. 16 BULLETIN 55, HAWAII EXPERIMENT STATION Green manure crops greatly benefit Hawaiian soils, many of which are lacking in organic matter. Some planters consider root cutting, such as is done by the plow, of value particularly during certain seasons. The roots of the banana plant usually grow out horizontally with little branching. If they are severed several feet from the plant the cut ends will send out a number of feeders, which spread in all directions. Root cutting should be done before the plants begin to fruit. In certain parts of Central America where the Gros Michel (Bluefields), and other tall-growing varieties are cultivated, banana plantations are located on forest-covered areas. The locality is first selected, consideration being given such important factors as climate, rainfall, drainage, likelihood of damage by flood and wind, and the feasibility of obtaining labor and supplying transportation. After surveys, trails, roadways, and main drainage ditches are completed, the underbrush is cut sufficiently to permit systematic lining and staking, after which the planting material is set at intervals of 12 to 18 feet each way, or otherwise, as the grower decides best. As the banana plants develop the land is kept cleared of undergrowth, and the remaining trees are removed until finally the forest is replaced by the field. The clumps of banana plants will have in- creased sufficiently in size and number by the end of the year to cover the fields with vegetation maintaining a condition of tem- perature and moisture not greatly unlike that formerly existing in the virgin forest. (For detailed information on the development of banana plantations, see 16, p. 21.) The above outlined method, with some modification, might be ap- plicable to vast areas of Hawaiian subforest lands at elevations of 500 to 2.000 feet. The excellent underdrainage of the geologically new lava soils would greatly lessen the extensive preparation and cultivation necessary on the lower lands where the Chinese variety is most commonly grown. A survey of the banana-growing possibilities on the island of Hawaii at elevations of 500 to 2,100 feet was made by the writer in 1924. Bluefields, Chinese, and several other varieties of the native cooking banana of the Maoli type were found in cultivation in clear- ings at elevations up to 2,100 feet. The plants were free from insect pests and disease and were making luxuriant growth, producing large bunches of fruit, specimens of which on ripening proved to be of excellent quality. Although banana culture at the higher eleva- tions requires a longer time to mature the fruit than it does at the lower levels, cost of production is considerably reduced by the simple methods of culture used, and by the natural rainfall, which makes irrigation unnecessary. It was also found that enough clean, healthy propagating material of the varieties could be assembled and multi- plied rapidly to start a plantation of no small consequence, and that all the stock needed could be obtained in the Territory, thus pre- cluding the introduction of disease and insect pests from other coun- tries against which quarantine regulations now exist. IRRIGATION AND DRAINAGE Where irrigation is to be practiced, the ditches should be laid out on contours enabling the water to cover every portion of each division BANANA CULTUBE IX HAWAII 17 of the field without washing the soil. Drainage ditches should also be provided to prevent the water from accumulating. Newly set fields require a light irrigation about once a week. The water should be admitted to ditches made between the rows when the plant- are well established. Thus centered the ditches will provide a more sub- stantial feeding system for the roots and lessen the tendency of the plant to produce suckers. After reaching the age of fruitfulness a field of Chinese bananas normally requires a thorough watering about every 15 days during the months of insufficient rain. Good drainage is absolutely necessary for the production of first- class fruit. It is just as important to maintain adequate drainage as to have efficient irrigation, and more harm is done by having too much water than by not having enough. Too much water causes water-logging and soil acidity. Deep rather than shallow drainage ditches are most satisfactory. WINDBREAKS Banana plants grow best in localities having little or no wind. The gentler trade winds are not to be feared, but continuous high winds whip the young leaves into ribbons and prevent normal growth. The plants, especially such as are weighted with fruit, may be blown down by unusually high winds, which, fortunately, seldom occur in these islands. Some varieties like the low and stocky Cavendish withstand heavy wind better than others. Of the taller growing varieties, the Brazilian has been found to be best adapted to windy exposures in the Hawaiian Islands. The local banana industry has not yet grown to proportions mak- ing it necessary to utilize all sheltered lands suitable for banana growing. Only such lands have been used as are naturally pro- tected from the prevailing northeast trade winds. Some of the windy localities probably could be utilized for banana culture by growing windbreaks on the windward side of the field, or on a surrounding area of 5 to 10 acres, as the situation requires. Several rows of the Brazilian banana might be utilized for the purpose. The panax (Nothopanax guilfoylia) which grows upright to a height of 15 feet, makes a good windbreak. More permanent wind- breaks may be obtained by planting such rapidly growing trees as the ironwood (Casuarina equisiti folia) and eucalyptus {Eucalyptus vobusta) alternately in rows 10 feet apart and of the same distance apart in the row. The mango (Mangifera indica) also withstands high winds and, on account of its dense top, makes an excellent windbreak. Grafted mango trees have the additional value of pro- ducing good fruit in season. The windbreak trees may be set in three rows 10 feet apart in alternate form with the same distance between trees in the row. The row nearest to the prevailing wind should consist of eucalyptus trees, which make tall, slim growth; the central row should be made up of two kinds of trees, eucalyptus and grafted mango arranged alternately in the row: and the row adjoining the field of bananas should consist entirely of ironwood. The horizontal roots of these 11862°— 26 3 18 BULLETIN 55, HAWAII EXPERIMENT STATION trees can be prevented from encroaching on the zone occupied by the bananas by maintaining a narrow ditch 3 or 4 feet in depth at a distance of about 4 feet from the row of trees adjoining the field. Good examples of controlling horizontal root growth of wind- breaks are to be found in different parts of the Territory. Vigorous and prolific plants can be grown in close proximity to tree wind- breaks where the ditch method is used. A windbreak of round, dense-topped trees intermixed with the taller topped forms makes an irregular and more satisfactory shelter than one of uniformly tall, dense trees. PRUNING Both vigor and productivity of the banana plant are greatly in- creased by proper sucker pruning. The plants soon lose their ability to collect and assimilate sufficient plant food to maintain all their suckers when developed to abnormally large fruiting condi- tions, as is often done for commercial purposes. Fruit of improved size and quality can be had by pruning out the poorer suckers and forcing each clump to produce two to four fruiting trunks. Grow- ers may time their crops to meet market demands. By choosing the right time to start new suckers, it is possible to bring in the greater part of the crop during the season of highest prices. A thorough knowledge of pruning requires considerable study and practice. The difference between desirable and undesirable small suckers is hard to determine. Undesirable specimens should be removed before attaining a height of 2 feet, for the larger they grow the more food they will take from the parent plant, and the more their young roots will interfere with the root system of the clump. Selected suckers of a size for transplanting should be so carefully removed as not to injure remaining suckers or the core and root system of the parent. The roots of the severed sucker should be removed before transplanting. Practically all the work in sucker pruning is done with a long- handled, chisellike cutting tool, commonly called a " sucker spud," which is very similar to the Hawaiian a o-o." After removal of some of the soil from around the sucker the spud is forced straight down between the sucker and the corm of the parent plant to mgke a clean cut without bruising either. In pruning out small, unde- sirable suckers care must be taken to cut far enough into the hard, Avhite part of the corm to prevent the suckers from sprouting again ana necessitating a repetition of the work. The large terminal bud of the flower stalk may be pruned out when the fruit has set and a few clusters of the staminate flowers have fallen. When the earlier leaves of the plant complete their assimilative function they hang pendant around the trunk, protect- ing it from the rays of the sun. If they are pruned out, the outer sheathing of the trunk may be injured and the whole plant may sutler . The dead leaves may be pruned out, however, and used for wrapping the fruit for shipment when the plants are set close to- gether and the trunks are Avell shaded by the foliage. When a iDimch of fruit forms about a leaf petiole the leaf should be pruned out to prevent its causing any irregularity of the fruit. BAN AX A CULTURE IN HAWAII 19 REPLANTING The number of years in which a banana plantation may be kept in production depends upon depth of plowing, physical condition of the soil, thoroughness of preparation, and nature of cultivation. Growers often find it necessary to remove the old rhizomes and other root material from the soil and to prepare the field thoroughly again after 4, 5, or 8 years, depending upon conditions. One of the most productive local fields of Chinese banana is now (1925) in its ninth year of production from setting of suckers. The soil in this field was deeply plowed and was in excellent condition when thoroughly prepared prior to setting selected suckers and has re- ceived theT best of care. Fields in certain parts of Central America are said to have continued to produce during 20 years from a single planting. HARVESTING AND SHIPPING The banana, like the avocado and some other fruits, ripens best when it is picked green. This fact has greatly helped to develop the banana industry of the Tropics as a source of supply of an all- the-year-round fruit for the numerous markets of the Temperate Zone. The best conditions for proper ripening of the banana rarely exists naturally in those parts of the world where the fruit is exten- sively grown, or in the still wider range where much of it is con- sumed. Usually, the jobber receiving the green fruit has the re- sponsibility of ripening it. A careful study of the banana showed the ripening process to be governed by highly important factors such as regulation of temperature, humidity, and fresh-air supply. Only in the carefully regulated ripening room is the high quality of the fruit developed. It is a well-known fact that Hawaiian bananas which are shipped to the markets of the mainland and prop- erly ripened in the ripening rooms are superior to the same kind of fruit cut for local market and ripened in the open air of retail stores. In regard to range of time of harvesting, the banana is less exact- ing than are most fruits. If the fruit is to be shipped long distances, it must be cut from the plant earlier than if intended for use nearer the plantation. The fruit should be allowed to get plump before the bunch is severed from the plant, but not to develop to the stage where it will ripen and decay before reaching the consumer. The exact stage of maturity suitable for certain occasions can be deter- mined only by experience. The terms " full," " too full," and the like are commonly used to express stages of maturity. The fruit should be given the greatest care during all the work of harvesting and shipping to avoid bruising. The bunches are cut from the plant with iy 2 to 2 feet of stem left above the fruit to serve as a convenience in handling it and to aid in keeping it fresh while in transit. Usually three men work together to harvest the fruit of the dwarf varieties, the first man holding the bunch, the second man severing it, and the third man carrying it to the nearest field road. In harvesting the fruit of the higher-growing varieties the cutter hacks the trunk slightly above the middle on the side toward which the bunch is to fall, taking care that it docs not fall against or injure any other plant. The top of the plant with its bunch of fruit is gradually lowered to a workman, who hold- the 20 BULLETIN 55, HAWAII EXPERIMENT STATION bunch while it is being severed. The bunches are then collected and placed on light autotrucks and taken to the packing shed, where they are set upright on straw. The packing shed, usually a rectangular structure with corrugated iron roof, has two open sides to permit convenient handling of the fruit. The earthen floor is covered with a liberal supply of straw to protect the fruit from bruising. The dimensions of the structure depend upon the size of the field to be accommodated, a convenient size being 20 to 40 feet, with one packing shed to each 20-acre unit of the plantation. Near the shed is the washing rack, consisting of a long ridgepole supported horizontally at about 7 feet above a slat floor, and from which are suspended ropes looped to support the bunches conveniently. The fruit is carried to the washing rack, where it is hung and then washed to remove dust, trash, and insects (pi. G, B). The fruit is finally returned to its place in the packing shed for weighing, marking, and grading. Four or five hours later, when the bunches have thoroughly dried, the fruit is inspected in accordance with the plant quarantine regulations of the United States Department of Agriculture and is ready for wrapping. In Hawaii each standard bunch of bananas used for exportation is wrapped separately in a protective covering consisting of (1) paper, (2) rice straw, and (3) banana leaves. The leaves are long, tough, and very light, and are bound about with cheap cord or the fibrous midrib of the banana leaf. Such wrapping material permits free circulation of fresh air about the fruit, and is deemed very necessary when shipping the fruit without refrigeration. The cost of wrap- ping is estimated to be about 5 cents per bunch of fruit. The local banana industry has developed slowly with the steady increase of proper shipping facilities between the islands and the mainland. Commercial production amounts to about *200,000 bunches annually. Table 7 gives the number of bunches and valua- tion of bananas exported from the islands since 1856, when the first shipment was made. As the banana industry in Hawaii continues to develop, methods of shipping the fruit will probably improve. The industry can not make rapid growth until shipping facilities are increased, and steamship companies are not likely to increase their special shipping equipment unless they are assured of a steady supply of freight. The interests of the two are mutual. The local banana grower has long been compelled to export his fruit as deck freight, which is not always a satisfactory method. A change of schedule, made re- gardless of perishable freight, may result in partial or complete spoilage of bananas, the loss of which the grower must stand. Venti- lation afforded deck freight may be better than that in the holds of some vessels, but neither the circulation nor the temperature of the air can be regulated as desired. Specially designed steamers having a part of their freighting capacity equipped with the modern cooling system, such as is used in transporting fruit similar dis- tances from Central American ports, would seem adaptable to Hawaiian banana transportation. The cooling system makes it possible to maintain the desirable temperature of 5G° F., in mod- erately warm climates such as occur between Hawaii and Pacific coast ports of the mainland. Bui. 55, Hawaii Agr. Expt. Station Plate 6 A.— Hand of "Ilai" bananas, a native variety of the Maoli group. One of the best kinds for rooking. A single fruit weighs a pound B. — Washing the bunches of fruit to remove dust and any insects lurking among the bananas. The fruit is then placed in the packing shed, where it remains about a day to dry thor- oughly. It is then wrapped for shipping BANANA CULTURE TN HAWAII 21 Table 7. ■Number of bunches and valuation of bundles exported from the Hawaiian lsj