U. S. DEPARTMENT OF AGRICULTURE. BUREAU OF PLANT INDUSTRY BULLETIN NO. 92. B. T. GALLOWAY, Chief of Bureau. )ATE VARIETIES AND DATE CULTURE IN TUNIS. BY THOMAS H. KEARNEY, PHYSIOLOGIST, PLANT BREEDING INVESTIGATIONS. ISSUED SEPTEMBER 6, 1906. WASHINGTON: GOVERNMENT PRINTING OFFICE, 1906. BULLETINS OF THE BUREAU OF PLANT INDUSTRY. , The work of the Bureau of Plant Industry, which was organized July 1, 1901, is classified under the general subjects of Pathological Investigations, Physiological Investigations, Taxonoinic Investigations, Agronomic Investiga- tions, Horticultural Investigations, and Seed and Plant Introduction Investiga- tions. All the scientific and technical publications of the Bureau are issued in a .single series of bulletins, a list of which follows. Attention is directed to the fact that the publications in this series are not for general distribution. The Superintendent of Documents, Government Printing Office, Washington, D. C., is authorized by law to sell them at cost, and to him all applications for these bulletins should be made, accompanied by a postal money order for the required amount or by cash. Postage stamps and per- sonal checks will not be accepted in payment for publications. No. 1. Relation of Lime and Magnesia to Plant Growth. 1901. Price, 10 cents. 2. Sperniatogenesis and Fecundation of Zamia. 1901. Price, 20 cents. 3. Macaroni Wheats. 1901. Price, 20 cents. 4. Range Improvement in Arizona. 1902. Price, 10 cents. 5. Seeds and Plants Imported. Inventory No. 9. 1902. Price. 10 cents. 6. A List of American Varieties of Peppers. 1902. Price, 10 cents. 7. The Algerian Durum Wheats. 1902. Price, 15 cents. 8. A Collection of Fungi Prepared for Distribution. 1902. Price, 10 cents. 9. The North American Species of Spartina. 1902. Price, 10 cents. 10. Records of Seed Distribution, etc. 1902. Price, 10 cents. 11. Johnson Grass. 1902. Price, 10 cents. 12. Stock Ranges of Northwestern California. 1902. Price, 15 cents. 13. Range Improvement in Central Texas. 1902. Price, 10 cents. 14. Decay of Timber and Methods of Preventing It. 1902. Price, 55 cents. 15. Forage Conditions on the Border of the Great Basin. 1902. Price. .15 cents. 16. Germination of the Spores of Agaricus Campestris, etc, 1902. Price, 10 cents. 17. Some Diseases of the Cowpea. 1902. Price, 10 cents. 18. Observations on the Mosaic Disease of Tobacco. 1902. Price, 15 cents. 19. Kentucky Bluegrass Seed. 1902. Price, 10 cents. 20. Manufacture of Semolina and Macaroni. 1902. Price, .15 cents. 21. List of American Varieties of Vegetables. 1903. Price, 35 cents. 22. Injurious Effects of Premature Pollination. 1902. Price, 10 cents. 23. Berseem. 1902. Price, 10 cents. 24. Unfermented Grape Must. 1902. Price, 10 cents. 25. Miscellaneous Papers: I. The Seeds of Rescue Grass and Chess. II. Saragolla Wheat. III. Plant Introduction Notes from South Africa. IV. Congressional Seed and Plant Distribution Circulars. 1903. Price, 15 cents. 2G. Spanish Almonds. 1902. Price, 15 cents. 27. Letters on Agriculture in the West Indies, Spain, etc. 1902. Price, ir> cents. 28. The Mango in Porto Rico. 1903. Price, 15 cents. 29. The Effect of Black Rot on Turnips. 1903. Price, 15 cents. :;<>. Budding the Pecan. 1902. Price, 10 cents. :: 1 . Cultivated Forage Crops of the Northwestern States. 1902. Price, 10 cents. 32. A Disease of the White Ash. 1903. Price, 10 cents. ."..".. North American Species of Leptochloa. 1903. Price, 15 cents. 34. Silkworm Food Plants. 1903. Price, 15 cents. ::.",. Recent Foreign Explorations. 1903. Price, 15 cents. .">>. The "Bluing" of the Western Yellow Pine, etc. 1903. Price, 30 cents. .".(. Formation of the Spores in the Sporangia of Khtaopus Nigricans and of I'hyconiyces Xitens. 1903. Price, 15 cents. 38. Forage Conditions in Eastern Washington, etc. 1903. Price, 15 cents. :'.!). The Propagation of the Easter Lily from Seed. 1903. Price, 10 cents, lo. Cold Storage, with Reference to the Pear and Peach. 1903. Price, 15 cents. 41. The Commercial Grading of Corn. 1903. Price, 10 cents. 42. Three New Plant Introductions from Japan. 1903. Price, 10 cents. [Continued on page 3 of cover.] Bui. 92, Bureau of Plant Industry, U. S. Dept. of Agriculture PLATE I. HARVESTING DEGLET MOOR DATES AT TOZER. (From a photograph by F. Soler, Tunis.) U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF PLANT INDUSTRY BULLETIN NO.' 92. ' B. T. GALLOWAY, Chief of Bureau. DATE VARIETIES AND DATE CULTURE IN TUNIS. BY THOMAS H. KEARNEY, PHYSIOLOGIST, PLANT BREEDING INVESTIGATIONS. ISSUED SEPTEMBER 6, 1906. WASHINGTON: GOVERNMENT PRINTING OFFICE 1906. BUREAU OF PLANT INDUSTRY. SCIENTIFIC STAFF. Patb&topte'f and Physiologist, and Chief of Bureau, Beverly T. Galloway. Pathologist mid J'Jii/siologist, and Assistant Chief of Bureau, Albert F. Woods. PATHOLOGICAL INVESTIGATIONS. Laboratory of Plant Pathology, Erwln F. Smith, Pathologist in Charge. Diseases of Fruits, Merton B. Waite, Pathologist in Charge. PHYSIOLOGICAL INVESTIGATIONS. Plant Breeding, Herbert J. Webber, Physiologist in Charge. Plant Life History, Walter T. Swingle, Physiologist in Charge. Soil Bacteriology and Water Purification, Karl F. Kellerman, Physiologist in Charge. Bionomic Investigations of Tropical and Subtropical Plants, Orator F. Cook, Bionomist in Charge. Drug and Poisonous Plant Investigations and Tea Culture Investigations, Rodney H. True, Physiologist in Charge. Physical Laboratory, Lyman J. Briggs, Physicist in Charge. TAXONOMIC INVESTIGATIONS. Economic Collections, Frederick V. Coville, Botanist in Charge. AGRONOMIC INVESTIGATIONS. Farm Management, William J. Spillman, Agriculturist in Charge. Grain Investigations, Mark A. Carleton, Cerealist in Charge. Arlington Experimental Farm, Lee C. Corbett, Horticulturist in Charge. Sugar-Beet Investigations, Charles O. Townsend, Pathologist in Charge. Western Agricultural Extension, Carl S. Scofield, Agriculturist in Charge. Dry Land Agriculture, E. Channing Chilcott, Expert in Charge. HORTICULTURAL INVESTIGATIONS. Pomological Collections, Gustavus B. Brackett, Pomologist in Charge. Field Investigations in Pomology, William A. Taylor and G. Harold Powell, Pomologists in Charge. Experimental Gardens and Grounds, Edward M. Byrnes, Superintendent. SEED AND PLANT INTRODUCTION INVESTIGATIONS. Seed and Plant Introduction and Distribution, Adrian J. Pieters and David Fairchild, in Charge. y, Edgi SPECIAL LABORATORIES, GARDENS, AND FARMS. Seed Laboratory, Edgar Brown, Botanist in AGBiC. DEFY* Mississippi Valley Laboratory, St. Louis, Mo., Hermann von Schrenk, Expert in Charge. Subtropical Laboratory and Garden, Miami, Fla., Ernst A. Bessey, Pathologist in Charge. Plant Introduction Gardens, Chico, Cal., Palemon H. Dorsett, Pathologist in Charge. Cotton Culture Farms, Seaman A. Knapp, Lake Charles, La., Special Agent in Charge. Editor, J. E. Rockwell. Chief Clerk, James E. Jones. SEED AND PLANT INTRODUCTION AND DISTRIBUTION. SCIENTIFIC STAFF. A. J. Pieters, Botanist in Charge. David Fairchild, Agricultural Explorer, in Charge of Foreign Explorations. W. W. Tracy, sr., Superintendent of Testing Gardens. John E. W. Tracy, Assistant Superintendent of Testing Gardens, in Charge of Congres- sional Seed Distribution. O. W. Barrett, Assistant. George W. Oliver, Expert. C. V. Piper, Agrostologist, in Charge of Forage-Crop Investigations. J. M. Westgate, Assistant Agrostologist, in Charge of Alfalfa and Clover Introduction. W. W. Tracy, jr., Assistant Botanist. Frank N. Meyer, Agricultural Explorer. Charles F. Wheeler, Expert. A. B. Connor, Special Agent. Nickolas Schmitz, Special Agent. John H. Tull, Special Agent, in Charge of Matting-Rush Investigations. Harold T. Nielsen, Scientific Assistant in Agronomy. 92 2 LETTER OF TRANSMITTAL U. S. DEPARTMENT OF AGRICULTURE, BUREAU OF PLANT INDUSTRY, OFFICE OF THE CHIEF, Washington, D. C., March 1, 1906. SIR: I have the honor to transmit herewith, and to recommend for publication as Bulletin No. 92 of the series of this Bureau, the accompanying manuscript, entitled " Date Varieties and Date Cul- ture in Tunis," by Thomas H. Kearney, Physiologist, Plant Breed- ing Investigations. The importance of this bulletin lies in the fact that it presents a key to the principal varieties of date palms the first available to Americans interested in this fruit. It gives, further, an accurate picture of the conditions under which profitable date culture is car- ried on in the northern edge of the Sahara, and can not fail to be of value to all prospective date growers. Acknowledgment is made of the courteous cooperation uniformly extended to Mr. Kearney by the authorities during his stay in Tunis. The valuable assistance rendered him by M. Hugon, director of agriculture and commerce, and by MM. Chervin, Minangoin, and Tellier, of the direction of agriculture, as well as by the controleurs civils at Tozer, Gafsa, Sfax, and Gabes, and by the caids of Tozer and Kebili, should be especially mentioned. The hospitality ex- tended by Captain Donau, commandant superieur at Kebili, and the great service rendered by him to the Department of Agriculture in having collected, prepared, and forwarded to Tozer 175 offshoots of the best varieties found in the Nefzaoua, merit especial acknowl- edgment. Prof. Milton Whitney, Chief of the Bureau of Soils, and Drs. F. K. Cameron and L. J. Briggs, of that Bureau, obligingly cooperated in furnishing mechanical analyses of the soil samples collected and chemical analyses of the soil and water samples. This paper has been submitted by the Botanist in Charge of Seed and Plant Introduction and Distribution, and was prepared as a result of Mr. Kearney's expedition to the oases of Tunis in search of new varieties of dates. The illustrations which accompany this paper are considered essen- tial to a full understanding of the text. Respectfully, B. T. GALLOWAY, Chief of Bureau. Hon. JAMES WILSON, Secretary of Agriculture. 92 343333 CONTENTS. Page. Introduction _ 9 Characteristics of the region _ _ 11 Geography 11 The Jerid 11 The Nef zaoua 17 Gabes 19 Gafsa 20 Climate 21 Temperature 21 Atmospheric humidity _ _ _ 26 Precipitation _._ ...._ 27 Irrigation and drainage _ _ . 28 Water supply _ _ _ 28 Irrigation system 31 Drainage system 33 Soils of the Jerid region 33 Texture 33 Fertility .'_.. 35 Alkali 36 Culture of the date palm _ 41 Size and value of the gardens _ _ 41 Labor and tenantry system 42 Propagation 43 Preparing the land _ 45 Planting 46 Irrigating 47 Manuring .... 49 Other cultural methods 50 Pollination and male palms _ _ 50 Ripening 51 Harvesting _ 52 Preserving _ 54 Varieties of the date palm in Tunis . - 55 Descriptions of the varieties 60 Varieties of primary importance . .. - - 60 Soft dates .... 60 Dry dates _.. 71 Varieties of secondary importance 74 Dry dates '_ 74 Soft dates .- 76 Varieties of minor importance 82 Drydates 82 Soft dates 84 Varieties imported but not included in the key 90 Varieties included in the key but not imported 92 Descriptive key to the characters of the fruits 94 Synopsis of the groups 96 Key to the varieties _ 97 Index 107 Description of plates 112 92 5 LLUSTRATIONS. PLATES. Page. PLATE I. Harvesting Deglet Noor dates at Tozer Frontispiece. II. Fig. 1. Alkali land in the midst of Tozer oasis. Fig. 2. Work- ing the soil of a date garden with the "messah," or short- handled hoe 112 III. Date palm showing ; ' straddling " of fruit cluster to prevent the breaking of the stalk ...-. 112 IV. Fig. 1. Tronja palm showing characteristic drooping, curved leaves. Fig. 2. A typical male date palm showing numerous leaves 112 V. Fig. 1. Menakher palm with numerous small suckers. Fig. 2. Old Menakher palm with two large fruiting suckers . . _ 112 VI. Fig. 1. Deglet Noor palm. Fig. 2. Lagoo palm. Fig. 3. The town of Nefta, with date garden in left foreground 112 VII. Fig. 1. Fteemy palms, El Oudiane. Fig. 2. Plantation of 6- year-old date palms at Nefta. A Fteemy palm in the fore- ground : 112 VIII. Dates, natural size: 1, Deglet Noor variety: 2, Menakher variety. 112 IX. Dates, natural size: 1, Tronja variety; 2, Boo Affar variety 112 X. Dates, natural size: 1, Horra variety; 2, Kenta variety; 3, Fteemy variety; 4, Mokh Begry variety 112 TEXT FIGURES. FIG. 1. Map showing the location of the Tunis oases with respect to other localities in Algeria and Tunis . _ . ... 12 2. Irrigation canal and diversion dam , Tozer oasis 31 3. Laborer holding a ' ' messah , " or short- handled hoe 44 4. Date-picker holding a " mengel," or straight-bladed sickle, used for cutting off the bunches of dates _ _ 44 5. Camel carrying date offshoots wrapped in palm fiber (leef) for transportation 45 6. Outlines of Menakher seed and fruit. (Natural size) 61 7. Outlines of Deglet Noor seed and fruit. (Natural size) 63 8. Outlines of Boo Affar seed and fruit. (Natural size) 66 9. Outlines of Tronja seed and fruit. (Natural size) 67 10. Outlines of Boo Fagoos seed and fruit. ( Natural size) 67 11. Tafazween seeds and fruits. (Natural size) 68 12. Outlines of Fteemy seed and fruit. (Natural size) 69 13. Outlines of Areshty seed and fruit. Natural size) _ . 71 14. Outlines of Horra seed and fruit. (Natural size) 72 92 7 ILLUSTKATIONS. FIQ. 15. Outlines of Kenta seed and fruit. (Natural size) 73 16. Outlines of Angoo seed and fruit. (Natural size) 74 17. Outlines of Thaby seed and fruit. (Natural size) 75 18. Outlines of Lemsy seed and fruit. (Natural size) _ 75 19. Outlines of Halooa Bayda seed and fruit. (Natural size) . _ 76 20. Outlines of Mokh Begry seed and fruit. (Natural size) 76 21. Outlines of Baydh Hammam seed and fruit. (Natural size) '77 22. Outlines of Kseba seed and fruit. (Natural size) 77 23. Outlines of Doonga seed and fruit. (Natural size) 78 24. Outlines of Besser Haloo seed and fruit. (Natural size) 78 25. Outlines of Okht Fteemy seed and fruit. (Natural size) 79 26. Outlines of Rhars seed and fruit. (Natural size) 79 27. Outlines of Lagoo seed and fruit. (Natural size)' _ 80 28. Outlines of Zekry seed and fruit. (Natural size) 81 29. Outlines of Khalt Mooashein seed and fruit. (Natural size) 81 30. Outlines of Khalt Deglaowia seed and fruit. (Natural size) 82 81. Outlines of Khalt Horraowia seed and fruit. (Natural size) 82 32. Outlines of Bayjoo seed and fruit. (Natural size) 83 33. Outlines of Remta seed and fruit. (Natural size) 83 34. Outlines of Hamra seed and fruit. (Natural size) _ _ 84 35. Outlines of Kenteeshy seed and fruit. (Natural size) 84 36. Outlines of Tantaboosht seed and fruit. (Natural size) _ _ _ _ 85 87. Outlines of Tozer Zaid Safra seed and fruit. (Natural size) 85 38. Outlines of Tozer Zaid Khala seed and fruit. (Natural size) 85 39. Outlines of Sayba Boo Dra seed and fruit. (Natural size) _ 86 40. Outlines of Kharooby seed and fruit. (Natural size) _ 86 41. Outlines of Gasby seed and fruit. (Natural size) _ _ 87 42. Outlines of Bent Segny seed and fruit. (Natural size) 87 43. Outlines of Ammary seed and fruit. (Natural size) 88 44. Outlines of Goondy seed and fruit. (Natural size) 88 45. Outlines of Karooy seed and fruit. (Natural size) 89 46. Outlines of Iteema seed and fruit. (Natural size) 89 47. Outlines of Khalt Hameed seed and fruit. (Natural size) 89 48. Outlines of Chedakh seed and fruit. (Natural size) 92 49. Outlines of Deglet Hamidatoo seed and fruit. (Natural size) 92 50. Outlines of Deglet Hassen seed and fruit. ( Natural size) 92 51. Outlines of Khalt Menakhry seed and fruit. (Natural size) 93 52. Selatny seed and fruits. (Natural size) 93 B. P. I. 302. DATE VARIETIES AND DATE CULTURE IN TUNIS. INTRODUCTION. During the autumn and winter of 1904-5, while traveling as agri- cultural explorer for the Office of Seed and Plant Introduction and Distribution, the writer, at the suggestion of Mr. W. T. Swingle, made two trips to the oases of southern Tunis in order to study the varieties of the date palm grown there and to secure offshoots of the more promising sorts for introduction into the United States. The first visit was made in October and November, the period when the fruits of most of the varieties are ripening and when the harvest is in full progress. On that occasion six weeks were spent in the more important oases, and a careful study of the chief varieties was made. This was considered an essential preliminary to selecting varieties for importation, as very little has been done by Europeans in study- ing the characters of the almost innumerable varieties of the date palm and in ascertaining the relative merits of the different kinds. Nowhere, perhaps, does a greater number of promising varieties 'occur within a restricted area than in these Tunis oases, and the opportunity for comparison of widely differing types was an excep- tionally good one. In the course of the investigations a collection of 97 samples, representing 93 distinct varieties, was obtained. De- scriptions of 105 varieties were drawn up on the spot from freshly gathered fruits, and in many cases the characters of the palms themselves were noted. The fruits of 85 varieties were photo- graphed in naturj^ize, and photographs of the trees of 34 varieties were made. vfk Much informaM^jras obtained regarding the fruits of the dif- ferent % varieties, H^Fsize, appearance, sweetness, flavor, time of ripening, producti|Bss, and keeping qualities. The season chosen for the visit allowej the interesting process of harvesting the dates to be observed. Attention was also paid to the subjects of irriga- tion, cultural methods, and of saline or " alkali " soils in relation to the date palm. 92 9 10 DATE VARIETIES AND DATE CULTURE IN TUNIS. As a result of the first visit to the oases, it was possible for the writer to decide upon the varieties that seemed most desirable for introduction into the southwestern United States. To procure these varieties a second trip to the region was made for the Office of Seed and Plant Introduction and Distribution in February, 1905, and three weeks were spent in collecting and packing the offshoots. In all about TOO offshoots, representing 56 varieties, were obtained, and it required a caravan of 90 camels to transport them to the railway. The importation of so large a number of varieties was thought desirable, because it was recognized that date culture in the United States is still in the experimental stage, and it is impossible to fore- see as yet what varieties will prove most satisfactory. It is quite possible that some of those which thrive best and are most esteemed in their native countries will not succeed with us. On the other hand, varieties that are less esteemed at home may develop valuable quali- ties when transplanted to this continent. Furthermore, in view of the great diversity of climate and soil existing in the parts of the United States where date culture is possible, it seems altogether probable that different kinds will be found adapted to different sec- tions. In that case the existence at some few central points in the Southwest of large collections of varieties will prove to be of cardinal importance in the development of this promising industry. For these reasons, an effort was made to secure a few suckers of every well-marked variety of any value, while, of course, especial endeavor was directed to securing a larger number of each of the finest and most highly esteemed sorts. In a few cases the latter aim was not realized, owing to the rarity of the palms and the reluctance of the natives to part with the suckers. Of the superb Menakher date, for example, one of the principal objects of the expedition, only nine offshoots could be obtained, and most of these were smaller than could be wished. Yet at least a few offshoots were imported of all but one variety of primary value, and only two or three of the varieties that were regarded as of secondary value are wanting in the collection. It might be added that at the time of writing (Oc- tober 1, 1905) from 75 to 95 per cent of the palms imported from Tunis six months previously are showing signs of growth in the different plantations in Arizona and California. The chief object of the present report is to furnish descriptions of the Tunisian varieties imported into the United States, so that they can be identified hereafter. It is recognized that owing to the large number of varieties that have been introduced during the past five years much confusion in regard to the identity of the different sorts is likely to arise unless some attempt is made to place their characters upon record. To this end a descriptive key has been 92 GEOGRAPHY OF THE JERID. 11 worked out, which it is believed will be found useful in identifying the Tunisian varieties. As nothing of the kind has heretofore been attempted so far as the date palm is concerned, it is hoped that, be- sides fulfilling its immediate object, this key will afford suggestions as to the characters that are most serviceable in distinguishing the varieties and will serve as a basis for future studies. To supplement the descriptions contained in the key, each of the varieties imported is discussed under the headings " Varieties of primary importance," " Varieties of secondary importance," " Va- rieties of minor importance," and " Varieties imported but not in- cluded in the key," with respect to the quality of the fruit, time of ripening, productiveness, trunk and foliage characters, resistance to alkali, etc. As an introduction to the study of the varieties, the important geographical and climatic features of the region are treated, 'together with the character of the water supply and the cultural methods in use. CHARACTERISTICS OF THE REGION. GEOGRAPHY. The principal oases of southern Tunis, in which the date palm is the chief culture, form four distinct groups, the Jerid, the Nef- zaoua, Gabes, and Gafsa, each group being separated from the others by wide expanses of desert. (See fig. 1.) Each group differs in many important features from the others, having its special peculiar- ities of climate, soil, and water supply, as well as its characteristic varieties of dates. The Jerid is for us by far the most important group of oases, for there are found in perfection some of the finest varieties of the date palm in the world. It is the only part of Tunis in which the choice Deglet Noor dates are produced in large quantity for European mar- kets, exporting annually from one and one-half to two and one-half million pounds of them. This report, therefore, deals chiefly with the Jerid oases. A brief account of each of the other groups is given in the present chapter, but the discussions of climate, water supply, soils, and culture of the date palm apply almost solely to the Jerid. When reference is made to some other region, it is especially des- ignated. THE JERID. The name " Jerid " (French spelling, Djerid) is an abbreviation of " Beled-el-Jerid " the " cities of date palms." The group con- sists of four oases Nefta, Tozer, El Oudiane, and El Hamma sep- 92 12 DATE VARIETIES AND DATE CULTURE IN TUNIS. arated one from another by several miles of barren, sandy, or stony desert. They lie at the northern edge of the Sahara Desert, nestling at the foot of a line of cliffs that forms the north bank of the Shott Jerid. The Shott, which is about 68 miles long from west to east, is in winter a large, shallow salt lake, and in summer a mud flat, covered toward its center with a shining white crust of salt, much resembling, therefore, the Salton Sink in southeastern California^ Its mean ele- vation is about TO feet above sea level. Toward the northwest it opens into the Shott Gharsa, continued still farther westward as the BoaSaac iK^ S A HL AN S\ E A "CONSTANTINE TUNIS R I A ugoizrt R A D E S E R T 'Ouargla FIG. 1. Map showing the location of the Tunis oases with respect to other localities in Algeria and Tunis. Shott Melrhirh, which borders the Oued Rirh oases of Algeria." Beyond the easternmost of the Jerid oases the Shott Jerid contracts into a strait, which connects it with the much narrower Shott-el- Fejej. The latter extends eastward to within a few miles of the sea, near Gabes. Near its western end the Shott Jerid is bordered on the north by a barren, rocky line of bluffs of the pliocene formation, which farther a See Bui. 80, Bureau of Plant Industry, U. S. Dept. of Agriculture, 1905, p. 18. 92 GEOGRAPHY OF THE JERID. 13 east rises into the Jebel Sherb range of mountains. This escarpment, known as 'the Draa-el-Jerid, runs nearly east and west. West of Nefta it ends in a promontory extending between the Shott Jerid and the Shott Gharsa. It is virtually the southern edge of an arid, gen- erally stony plain, almost devoid of vegetation, which extends north- ward to Gafsa and beyond, rising gradually into the elevated plateau of central Tunis. This plain is intersected by desolate ranges of hills and by deep ravines that contain water only at long, irregular intervals. At the southern base of the Draa-el-Jerid bluffs, and sloping toward the Shott Jerid, lie the three oases of Nefta, Tozer, and El Oudiane, the first being the westernmost. Tozer is 15 miles east of Nefta and El Oudiane about 6 miles east of Tozer. These three oases are well sheltered from the north wind by the terrace behind them, but lie open to the south. On the other hand, El Hamma, 5^ miles north of Tozer, lies on the northwestern side of the Draa-el-Jerid, having the Shott Gharsa to the west, and while protected on the south and east sides it is much exposed toward the north and west. In general aspect all four oases are much alike. They consist of almost unbroken forests of date palms, divided up into many gar- dens that are separated by mud walls and intersected by innumerable irrigation and drainage ditches. The total number of date palms in the region, is variously estimated at from 600,000 to 1,000,000. It has been estimated that the average annual production of dates in the Jerid is about 34,700,000 pounds, of which somewhat more than 5 per cent are of the Deglet Noor variety. (See p. 63.) Of the total product of other varieties, about one-third is consumed on the spot, the rest being exported to various parts of northern Africa. In the shade of the palms (Pis. I; V, fig. 2, and VI) are grown many other kinds of fruit trees oranges, olives, figs, apricots, peaches, pomegranates, and jujubes interlaced with large grape- vines that often hang in festoons from the palm trunks. Beneath the trees are small plots of garden vegetables, barley, and alfalfa. Neither date palms nor other trees are planted with any regularity, and the growth is often so dense that the garden resembles a tropical j ungle. Very beautiful are these gardens in the spring, when the apricot and peach trees are in blossom here and there among the palms and the figs and vines are putting forth their leaves. In autumn, when the dates are ripening, the color effects, especially when the tops of the palms are lit up by the last rays of the setting sun, are some- o By Dollin du Fresnel, Le Djerid Tunisien. Bui. de la Soc. de Geogr. Comm. 22: 38 (1900). 92 14 DATE VARIETIES AND DATE CULTURE IN TUNIS. thing that once seen can never be forgotten. The great clusters of fruit, displaying every tint from bright yellow, through orange, vermilion, and maroon, to plum purple and chestnut brown, with their brilliant yellow or rich orange ivory-like stalks, contrast su- perbly with the dull bluish or gray green of the feathery crowns of foliage. It is small wonder that a whole folklore of poetic legends and proverbs has grown up around the date palm in the regions where it flourishes. The oases, especially Nefta, were formerly much exposed to the encroachment of the wind-blown sand of the desert, but since the French occupation the forestry service has taken effective measures to protect them from this danger. Around each oasis, at a distance from the edge of the gardens generally of 1,000 feet, although vary- ing according to circumstances, a mud wall, surmounted by a fence of palm leaves, has been erected. The sand drifts against this, form- ing an artificial dune sloping outward. As fast as this dune increases in height, the palisade is built higher. The slopes of the dune itself are planted with tamarisks, retain, and other desert shrubs suitable for binding the sand. The. zone between the palisade and the gardens is strictly forbidden to the domestic animals that were formerly pastured there, as they kept the soil in a loose condition and prevented the growth of the natural vegetation that helps to hold it in place. At the most exposed points a series of outer palisades, erected at regular intervals, arrests a good part of the sand before it can reach the barrier which is nearest the gardens. a A number of these legends and beliefs are related by Charlet (Les Palmiers du Mzab, Bui. Soc. G6ogr. d'Alger, 1905. Mohammed enjoined the care of the date palm as an almost religious duty, saying, "The palm is your aunt the sister of your father Adam." He also spoke of the date as " the only fruit which has in heaven the same flavor as upon earth," and described in these glowing terms the palms that grow in paradise: "Trunks of gold, spathes of gold, branches of gold, leaves of gold, stalks of gold, petals of gold, fruits as large as buckets, softer than butter, sweeter than honey." Another Arab poet imagined thus the dates of paradise : " They will be whiter than milk, more transparent than honey, softer than butter; they will have no stones." The origin of the date palm is often the theme of Mohammedan writers. " When God had shaped Adam's body with his hands, a little of the earth which He had used to fashion in his image our first father stuck to his fingers. He rolled it between his hands, making from it the trunk of the palm." The Arabs profess to see many points of resemblance between the date palm and man, its friend and ally. " Like man, it holds up its head; like man, it has a companion of a different sex. Its heart (terminal bud), immaculately white, is as tender and delicate as the brain of a man, the least hurt causing its death. Like man, it fears cold. If one of its branches be cut off, it does not grow out again, and thus is like a man's limb. If one cuts off its head, it dies. The fiber (leef) that surrounds its head resembles human hair." Tho little circle, about 1.5 millimeters in diameter, that is found on the back of the stone is believed to be the impress of the seal of Solomon. 92 GEOGRAPHY OF THE JERID. 15 The Jerid region was evidently occupied by the Romans, and frag- ments of structures belonging to their epoch are frequently met with. Both Nefta (Nepte) and Tozer (Thusuros) are situated on or near the site of ancient Roman towns. Although frequently harried and pillaged by the nomadic Arabs and by other wild tribes of the desert, the oases of the Jerid have been, so far as we know, in a continuous state of cultivation throughout the Christian era. An Arab author of the eleventh century celebrated in glowing terms their fertility of soil and the beauty of their dense forests of date palms. " No other place in Africa," he wrote, " produces so many dates." Until the completion of the railway from Sfax, on the east coast of Tunis, to the rich phosphate mines a few miles to the west of Gafsa (see map, fig. 1), the main artery of communication of the Jerid with the coast was the road, or rather trail, across the Shott Jerid, through the oases of the Nefzaoua, and then along the southern bank of the Shott-el-Fejej to Gabes, the total distance from Tozer to Gabes being about 120 miles. All the dates at that time exported from the Jerid to Europe had to be carried over this road by caravan. Now, however, Tozer is only about 35 miles from the end of the rail- way, and communication with the outside world is comparatively easy. The total population of the Jerid oases is about 30,000, Tozer and Nefta each counting about 9,000 inhabitants. Practically this entire population is supported by date culture, as the other agricultural products of the oases are of so little importance as to be almost negligible and only a very small fraction of the population sup- ports itself by manufacturing various fabrics. Nefta, the most western oasis of the Jerid, is said to occupy over 6,000 acres. The number of date palms it contains is variously esti- mated at from 180,000 to 385,000, of which only 14,000 are said to be of the Deglet Noor variety." The oasis consists of two distinct parts ; on the north a deep basin, called by the French the " Corbeille " (basket), in which arise the springs that water the gardens, and on the south the fan-shaped larger portion, extending to the low salt flats that fringe the Shott Jerid. The town of Nefta (PI. VI, fig. 3), the holy city of southern Tunis, lies between the two segments of the oasis and is itself separated into two parts by a deep'ravine (shown in the foreground of PL VI, fig. 3). Through this ravine runs the stream that carries the waters of the springs from the " basket " to the lower part of the oasis. The palms that occupy the " basket " are of unusual beauty. It is said that a few years ago an English But by the same authority the total number of all kinds is given as only 180,000. 92 16 DATE VARIETIES AND DATE CULTURE IN TUNIS. company made an unsuccessful attempt to purchase this part of the oasis. Better sheltered as it is than Tozer, especially on the north, and said to possess a more fertile soil, Nefta is well situated for date growing, and its palms yield fruit of high quality. Its gardens are celebrated for their beauty, containing many orange, apricot, fig, and other fruit trees, in addition to the date palms, which are largely of choice varieties. More vegetables, grain, and alfalfa (PL VII, fig. 2) are grown here than in the other oases of the Jerid. On the side toward the Shott new palm gardens are being established (PL VII, fig. 2) and are planted as far as possible to the Deglet Noor variety. Tozer oasis lies about 15 miles east of Nefta. The oasis proper extends eastward and southward from the town of Tozer, which, like all the towns of the Jerid, occupies high, open ground outside the gardens. It is the political capital of the Jerid region. The elevation of the town above sea level is about 153 feet, but the oasis is several feet lower. The area of this oasis is variously given as 2,650, 5,400, and 7,400 acres, but it is probably larger than that of Nefta. Different authorities state the number of palms contained in this oasis at from 250,000 to 417,000, of which only about 14,000 are of the Deglet Noor variety. The gardens of Tozer differ from those of Nefta in the smaller development of subsidiary cultures. The chief fruit trees, other than date palms, are figs and pome- granates. The oasis of El Oudiane begins about 5 miles east of the town of Tozer and extends for about 5 miles along the northern border of Shott Jerid, in a band that is from one-half mile to 2 miles wide. It lies so near the Shott that in winter the salt water sometimes rises nearly to the gardens. It is generally described as a group of five oases, but these are practically continuous, although each has its own village. The westernmost, known as El Degache, contains the finest gardens. The terrace, at the base of which the oases lie, is here much higher and closer to the gardens than at Tozer and Nefta, and El Oudiane is the best protected from the north wind of all the Jerid oases. Hence its dates, especially those of the Deglet Noor variety, are admitted on all sides to be the finest produced in the region. There are estimated to be from 120,000 to 212,000 date palms in the El Oudiane oases. As 8,000 of these are said to be Deglet Noors, the percentage of that variety is considerably higher than in the other oases. Besides the magnificent date palms, there are about a The " basket " of Nefta reminds one of the sunken gardens of the Oued Souf (Bui. 86, Bureau of Plant Industry), but is much larger than any of them 92 GEOGRAPHY OF THE NEFZAOUA. 17 25,000 olive trees in the El Oudiane group, most of these being at Degache, where much oil is made for local use. There is also an abundance of other fruit trees, oranges, figs, pomegranates, apri- cots, grapevines, and even a few bananas. In fact, the gardens of El Oudiane are among the best kept and the most attractive in the Sahara. The population is more active and laborious than that of the other oases of the Jerid. El Hamma, situated about 5J miles north of Tozer, lies on the northwest point of the Draa-el-Jerid terrace, on the south declivity of which the other oases are placed. The oasis slopes westward to the Shott Gharsa, instead of toward Shott Jerid. It is practically unsheltered from the north wind, which is probably the chief reason why its dates are the poorest of the region. It contains only 60,000 or 70,000 palms, of which but 800 are Deglet Noors. With a few ex- ceptions, the gardens of this oasis are neglected and have grown up in weeds and grass. Many of the palms receive no attention whatever, and many seedlings of inferior quality have been allowed to spring up. The population is sparse and seems to be thoroughly disheart- ened. Dates are said to mature less perfectly here than in the other oases. THE NEFZAOUA. The region known as the Nefzaoua occupies a narrow peninsula that is bounded on the south by the eastern end of the Shott Jerid and on the north by the Shott-el-Fejej. The latter, which is merely a prolongation of the former, extends eastward to within 14 miles of the coast, near Gabes. From Fetnassa, the northwesternmost oasis of the Nefzaoua group, to Kriz (El Oudiane), the nearest point in the Jerid, the distance is about 30 miles, the road leading diag- onally across the salt-crusted mud flats of the Shott Jerid. From Kebili, the capital of the Nefzaoua (see map, fig. 1), to Gabes, on the coast, the distance is about 64 miles as the crow flies, the direction being a little north of east. By the road usually traveled, which follows the south shore of the Shott-el-Fejej, the distance is some- what greater. Before the railway from Sfax to the phosphate mines Avest of Gafsa was built this road formed the principal outlet to the coast for the Jerid as well as the Nefzaoua oases. Along this route there are a few small oases, but no important ones are en- countered until one nears Gabes. The Nefzaoua comprises a large number of oases more than 1,000, according to the estimates of reliable authorities. Most of these, however, are mere small groves of palms, only forty of them attain- ing any considerable size. They are situated both on the north and the south slope of the stony ridge that forms the backbone of the 30618 No. 9206 2 18 DATE VARIETIES AND DATE CULTURE IN TUNIS. peninsula. This ridge is the western extension of the desert moun- tain range known as the Jebel Tebaga, which forms the southern border of the Shott-el-Fejej. The oases that are on the south side of this ridge are naturally more sheltered from the north wind and better situated for the ripening of dates than those on the north side. The population of the Nefzaoua is stated to be 25,000, distributed in 45 villages. The total number of date palms in the region is estimated by one authority to be 280,000, by another over 1,000,000. The first estimate is probably more nearly correct. It is a pecu- liarity of the Nefzaoua, which places it in strong contrast with the Jerid, that the oases are mostly situated upon the higher lands. The reason is that nearly all the springs are found craterwise at the summits of small volcano-like hillocks, and the gardens of date palms have grown up around them. The water supply is abundant, and owing to the situation of the springs with relation to the gar- dens irrigation is generally easy. In the oasis of Menchia, however, the gardens are generally some distance away from the springs, and water is conducted to them by means of tunnels that have been bored into the sides of the hills in which the springs rise. Some of these tunnels are said to have been constructed in the times of ancient Rome, this region also having been occupied by the Romans. In the Nefzaoua, as in the Jerid, the water sheet is located in cretaceous strata. Menchia is the most important of the oases on the north side of the ridge. Its soil is sa^ndy and contains much gypsum, but not an excessive amount of the more readily soluble salts. On the south slope the oasis which pertains to the two villages of Tlemine and Mansourah is the largest, and its gardens are the best kept of the region. It is said to contain 29,000 palms, while the next largest oasis, Kebili, contains 20,000. In these two oases the soils are gen- erally excellent, although frequently a trifle salty. The culture of the date palm is generally given less care in the Nefzaoua than in the Jerid. Many of the gardens have been allowed to grow up in seedlings of poor quality and are almost choked with weeds. The Deglet Noor variety has not heretofore been grown in the Nefzaoua, although the conditions would appear to be perfectly suitable for it. Recently the forestry service has taken some steps toward establishing its culture in some of the oases. The growing of other fruit trees and of crops of vegetables, cereals, and forage plants among the palms receives much less attention than in the Jerid. A great deal of trouble has resulted from the incursion of wind-blown sand, and here, as in the Jerid, the forestry service has had to under- take the protection of the oases by constructing palisades and by prohibiting the pasturing of animals on the outskirts of the gardens. 92 GEOGRAPHY OF GABES. 19 South of Kebili there is a region of sand dunes, and here the palms, according to M. Minangoin, inspector of agriculture, are grown in sunken gardens, similar to those of the Oued Souf region,* but on a smaller scale. In the oasis of Douz, about 16 miles south of Kebili, this form of date culture reaches its highest development in Tunis. There basins among the dunes are excavated to a depth of about 13 feet and often 100 to 130 feet square (the sand being carried out in baskets) in order to plant a dozen or so palms and a few other fruit trees. The palms grown with such an enormous expenditure of labor almost always belong to inferior varieties. During several months of each year most of the population of this oasis migrates in search of pasturage for its flocks. Upon the return of the inhabitants they must immediately set to work to clear out the sand that has invaded their gardens, a task that requires nearly as much labor as the original excavation. GABES. In extreme southern Tunis the Sahara Desert practically reaches the seashore, forming the region known as the "Aarad." One of the largest and most flourishing groups of oases in the country is that which has for its center the seaport town of Gabes. These oases are well supplied with water, those nearest Gabes chiefly by means of a series of little dams in the Oued Gabes (Gabes River) and its branches, the more distant ones from springs and wells. The large oasis of El Hamma of the same name as one in the Jerid region is famous for its hot springs. This oasis has an area of about 4,000 acres, and the combined area of those nearer Gabes is said to be about the same. About 400,000 date palms are estimated to exist in the oases of Gabes and El Hamma together. At Gabes the humidity, due to the proximity of the sea, prevents the successful growing of the finer varieties, notably the Deglet Noor. While the date palm itself thrives admirably in the Gabes region, and a great number of varie- ties exist there, the fruit produced is far inferior in flavor and sweet- ness to that of the Jerid and the Nefzaoua. Moreover, it is said not to keep well and easily to become moldy. The same criticism applies to the dates grown on the neighboring island of Jerba, where also there are about 400,000 palms. b But at El Hamma, although only l^l miles inland, the quality of the dates is appreciably better. See Bui. 86, Bureau of Plant Industry, U. S. Department of Agriculture, 1905. & It is interesting to know that some kinds of dates can be ripened on the seacoast, even considerably farther north than Gabes. M. Minangoin, inspector of agriculture at Tunis, in a letter to the writer, describes a small oasis of 4,000 to 5,000 palms, situated on a sand spit near Susa (Sousse), about 120 miles north of Gabes. Two kinds of dates are grown, of one of which the fruits must be eaten the day they are gathered, while the other kind can be kept for only 92 20 DATE VARIETIES AND DATE CULTURE IN TUNIS. In respect to other cultures, however, Gabes is easily first among the Tunis oases. Garden vegetables grow to perfection beneath the palms and mature so early that were there better facilities for transportation there would be a large profit in shipping them to European markets. Alfalfa grows beautifully and gives a rapid succession of cuttings throughout most of the year. Large yields of barley are obtained. Fruit trees of various kinds, but especially figs and pomegranates, are abundant and produce fruit that is highly esteemed throughout Tunis. Gabes is celebrated for the production of a small, deliciously flavored banana that is exported in some quantity to Europe. The grapevine grows to enormous size, and individual vines that produce 330 pounds of fruit are said to be not uncommon. Notwithstanding the scanty rainfall, plantations of oil olives in land that is not irrigated, similar to those of Sfax, are being established on the outskirts of some of the oases. GAFSA. The town of Gafsa is situated about 50 miles northeast of Tozer, the capital of the Jerid, and is connected with Sfax, on the east coast of Tunis, by a railway about 125 miles long. The elevation of Gafsa above sea level is about 1,150 feet. Tributary to the oasis of Gafsa itself are one or two other oases of small importance. Gafsa oasis contains from 50,000 to 65,000 date palms. These belong mostly to inferior varieties, and the dates produced are of mediocre quality. Because of its much greater elevation this locality is entirely unsuited to choice varieties, such as the Deglet Noor. The water supply is more than ample for the present extent of the oasis. The date is here hardly a more important' crop than the olive, of which there are many thousands of trees. Oil varieties predominate. At the begin- ning of the Christian era Gafsa (then known as Capsa) was included in the great olive zone that extended from the east coast of Tunis across into Algeria, and of which only scattered fragments remain. four or five days. These must be picked from the bunches as fast as they ripen, which necessitates climbing each palm every day until all of its product is harvested. These dates are sold in the markets of Susa at a rather high price, as they ripen at a time when other fresh fruit is not obtainable. They are eaten only by the natives, Europeans holding them in small esteem. The high value set upon them by the natives is shown by the fact that the off- shoots are sold at a price of $2 apiece. While the two varieties grown at this locality are doubtless of little intrinsic value, it is remarkable that dates of any sort will mature under these climatic conditions ; for at Sfax, where the sum- mers are slightly hotter than at Susa, the normal sum total of mean daily temperatures from May 1 to October 31 is only 1,968 F., and the normal sum of mean daily maxima during the same period is only 3,375 F. 92 TEMPERATURE. 2 1 At the present time the culture of the olive as carried on at Gafsa leaves much to be desired, and the gardens are generally not well cared for. The pomegranates of Gafsa are considered the best grown in Tunis. CLIMATE. The climate of southern Tunis is essentially that of a desert, al- though modified by the nearness of the sea. This modification is, of course, most marked at Gabes, on the coast, which has a more humid atmosphere and lower summer temperatures than the other oasis groups, and is consequently not well adapted to the culture of the finest varieties of dates. At Gafsa the air is drier than at Gabes, but the high altitude (1,000 feet) lowers the temperatures and shortens the summer to a degree that renders this oasis unsuitable for the late- ripening varieties. Only in the Jerid and the Nefzaoua oases do we find the climatic conditions that are necessary for the perfect ripening of the finest sorts of dates. TEMPERATURE. In the following tables data are given for five localities in Tunis where the date .palm is the principal culture, viz, Tozer and Nef ta (Jerid), Kebili (Nefzaoua), Gabes, and Gafsa. The normals for the different localities and for different months have been compiled from records of observations covering periods of unequal length, being from nine to thirteen years at Tozer. The monthly normals for Gabes and Gafsa have been corrected so as to agree with the normals of fifteen years for each seapon (winter, spring, summer, and autumn). All temperatures are given in degrees Fahrenheit. a As given by G. Ginestous (Etude sur le Climat de la Tunisie, Bui. Dir. Agr. ft Com., Tunis, 1902, pp. 64, 210, 334, 413; 1903, p. 103). The discrepancy be- tween tbe seasonal normals given by this author and the monthly normals compiled from various sources is usually only a fraction of 1 degree Fahren- heit for each month, although sometimes amounting to 3 or 4 degrees. The monthly normals have been compiled from the records published in the Annales du Bureau Central Meteorologique de France and in the quarterly Bulletin de la Direction de 1'Agriculture et du Commerce de Tunis. Those for Nefta and Kebili, localities for which seasonal normals are not given by Ginestous, are based upon short periods of observation, in no case exceeding six years, and in some cases of only three years, although generally four or five years. 92 22 DATE VARIETIES AND DATE CULTURE IN TUNIS. TABLE 1. Normal mean temperatures of localities in the desert regions of Tunis, Algeria, and the United States. Month. Tunis. Algeria. United States. 1 1 1 W 1 , , J E i 1 4 a M 5 x" & |j 2 <5 i af it .9 to ^ 1 January ... 51.3 55.9 62.1 68.7 76.1 86.2 92.0 92.0 83.1 73.0 61.7 52.3 50.5 56.3 61.1 69.2 74.5 84.3 89.1 88.8 83.8 72.9 61.4 53.0 49.6 56.5 61.7 71.9 74.8 84.1 89.4 87.0 82.5 72.5 59.8 52.0 51.8 55.6 59.7 64.2 69.2 76.3 81.3 81.0 80.0 72.8 62.9 54.3 49.2 53.7 58.1 64.2 71.4 80.4 85.6 a?. 4 81.7 71.3 59.8 48.6 50.5 53.2 58.3 mi 71.8 80.6 87.1 85.8 78.8 67.6 57.2 51.3 67.1 47.3 49.8 54.9 64.0 74.8 86.0 92.1 85.1 83.7 68.4 58.5 48.9 67.8 46.8 51.8 59.9 66.4 73.6 82.4 90.7 86.0 78.1 63.5 52.9 45. 66.4 49.8 54.3 53.9 67.0 74.4 83.9 90.2 88.2 81.4 69.3 58.5 52.3 68.6 54.1 58.6 63.9 69.9 76.9 84.4 91.2 90.4 84.3 72; 4 62.3 55.9 72.0 55.9 (50.5 68.4 79.7 87.5 96.6 101.3 99.7 89.5 78.4 67.0 57.4 February March . . . April M? y .::.:::::::::::::::::::::::: June July August Rfiptftrn V>r October JfovftTn'bpr December Year 71.2 70.4 70.1 67.4 67.4 78.5 Comparing the Tunis localities among themselves, we notice that during most of the year the Jerid oases (Tozer and Nefta) are the warmest, and that next to them is the Nefzaoua (Kebili) . In Novem- ber, December, and January, however, the highest means are reached at Gabes, on the seacoast. The normal yearly means are higher in the Jerid and the Nefzaoua than in any of the Algerian oases. The difference is particularly noticeable during the Avinter months, when the means are decidedly lower in the Algerian oases than in those of the Jerid and the Nefzaoua. The normal means of most months are higher in the Jerid and Nefzaoua oases than at Phoenix, Ariz., but lower than at Yuma, Ariz. They are much lower in every month than at Volcano Springs, Cal. TABLE 2. Normal mean maximum and minimum temperatures of localities in the desert region of Tunis. Month. Mean maxima. Mean minima. Tozer. Nefta. Kebili. Gabes. Gafsa. Tozer. Nefta. Kebili. Gabes. Gafsa. January 59.4 65.5 72.5 81.3 89.1 99.7 107.1 104.6 93.7 83.2 70.5 60.3 63.7 70.0 76.1 86.5 89.0 99.2 104.9 103.8 98.3 86.1 76.1 71.0 57.9 65.8 72.5 84.4 88.3 96.9 103.8 101.3 95.1 82.6 70.6 61.1 62.7 67.6 71.3 76.0 78.9 85.3 90.8 91.4 91.9 83.6 73.3 65.6 59.5 66.2 70.4 80.7 85.2 96.5 102.8 101.2 96.2 84.0 75.0 60.2 42.8 46.5 52.3 56.8 65.3 74.1 77.6 79.5 72.5 63.1 53.2 44.7 eoT 37.7 41.3 47.3 54.1 60.2 69.2 73.2 74.4 69.5 58.1 50.5 40.1 39.2 41.9 48.2 56.8 60.2 68.2 73.4 72.2 69.8 60.6 48.2 42.4 40.7 43.6 48.6 53.5 58.0 67.2 71.0 71.3 71.0 61.5 50.5 44.2 56.8 39.5 39.3 44.6 49.9 56.3 63.9 69.7 69.1 66.0 57.3 47.2 37.7 February March April.. May June July August September October November December Year 82.2 85.4 81.7 78.2 81.5 56.3 56.8 53.4 92 TEMPERATURE. 23 As is shown by the foregoing table, the normal yearly maxima are highest in the Jerid oases (Tozer and Nefta) and are lowest at Gabes, on the coast. In winter the maxima are higher at Nefta, but lower at Tozer than at Gabes. At Tozer the minima are higher for nearly every month than at any other locality in Tunis, while at Nefta those for June, July, and August are higher than at any other locality excepting Tozer. Comparing Gafsa, which has an elevation above sea level of 1,000 feet, with Gabes, on the coast, we find the maxima higher at the former point in all seasons except winter. The minima are lower at Gafsa than at Gabes in every month of the year. A climatic factor upon which the success of date culture largely depends is the sum total of heat received during the ripening period, which can be taken as comprising the six months from May 1 to October 31. As it is still a question whether the sum total of the daily means or those of the daily maxima give the best expression of this factor, both sums have been computed for the Tunis locali- ties, and are given in the following table. Following the sugges- tion made by Mr. W. T. Swingle, 6 the sums of the daily means are based upon the excess of the normal monthly means over 64.4 F., while in computing the sums of the daily maxima above 64.4 deduc- tion has been made for normal monthly minima that fall below that temperature. a As pointed out on p. 21, however, the results for Nefta and for Kebili are based upon too short periods of observations. Bui. 53, Bureau of Plant Industry, pp. 65-68. 92. DATE VARIETIES AND DATE CULTURE IN TUNIS. TABLE 3. Sums of daily mean and daily maximum temperatures above 64-4 f- from May 1 to October 31, at localities in the desert regions of Tunis, Algeria, and the United States.** Locality. Sum of daily mean Sum of daily maxi- mum Period covered by observations. Remarks. tures. tempera- tures. Tozer, Tunis 3,555.5 5,818.5 9 to 13 years All varieties including Deglet Noor, ripen perfectly. Nefta, Tunis 3,277.7 5,710.4 3 to 6 years Do. Kebili, Tunis 3, 183. 1 5 357 6 4 to 5 years Several first-class varieties ripen perfectly. Deglet Noor not yet CKbes, Tunis . 2,272.7 3,936.5 15 years grown. Finest varieties do not ripen well; even second and third class dates Gafsa, Tunis 2,738.1 4,943.9 do do not always ripen perfectly. Too cold to mature the finest vari- eties. Biskra, Algeria... 3,304.0 5,489.0 10 years (means), 12| years (maxima). Many varieties ripen perfectly, but the Deglet Noor is generally un- Ayata, Algeria... 3,488.0 5,932.0 3 years (means), 4 years (maxima). satisfactory. Deglet Noor ripens well in hot sum- mers, imperfectly in cool sum- mers. Phoenix, Ariz .... Salton, Cal 3,019.0 4 823 5,523.0 7 306 Many years (means) , 4 years (maxima). 12 years (means) 2 Many varieties ripen well, but not the Deglet Noor. Dates not grown average years (maxima). It would appear that for purposes of comparison of different localities as to their suitability for the culture of fine varieties of dates the sums of the daily maximum temperatures are more satis- factory than those of the daily means. For at Biskra, Algeria, where the Deglet Noor seldom ripens properly, the normal sum of the daily means is higher than that given above for Nefta, and only 250 degrees lower than at Tozer, yet at both of these Tunis localities the Deglet Noor rarely fails to mature, while the normal sums of the daily maxima both at Tozer and at Nefta are considerably higher than at Biskra. Furthermore, at Ayata, Algeria, in 1891, when Deglet Noor dates ripened "very slowly and imperfectly," the sum of the daily means was 3,431, or only 124 degrees lower than the normal for Tozer as given in the table. But in favor of the sum of the means rather than of the maxima is the fact that at Ayata, where the Deglet Noor does not ripen well every season, the normal sum of the maxima is nearly 100 degrees higher, while that of the means is about 70 degrees lower than at Tozer. At Phoenix, Ariz., where the Deglet Noor will probably not mature, the sums of daily mean and daily maximum temperatures are several hun- dred degrees lower than at Tozer. At Salton, Cal., however, both o The sums for Biskra and Ayata, Algeria, and for Phoenix and Salton, in the United States, are those given by Swingle, Bui. 53, Bureau of Plant Industry, pp. 66 and 68. As explained by Mr. Swingle, the method of observing tempera- tures formerly used at Salton has probably made the sum for that point appear to be higher than is actually the case. 92 TEMPERATURE. 25 sums are so very much higher than at Tozer that, even when we make a considerable allowance for the probable overestimate, due to the way the observations have been taken at Salton (see p. 24), we can not doubt that the Salton Basin is hot enough for the perfect ripen- ing of all the Tunis varieties of dates. At Gabes, on the coast of Tunis, only second or third rate varieties are grown, and even these often fail to mature well, as would be expected from the low sums of temperature (much lower than at Tucson, Ariz.). At Gafsa, also, where the sums of the daily mean and daily maximum temperatures are, respectively, nearly 300 and nearly 500 degrees lower than at Phoenix, none of the first-class varieties can be successfully grown. A comparison of the weather of several successive years at Tozer during the six months that are most decisive in the ripening of dates, with statements of the character of the succeeding crops, is presented in the following table : TABLE 4. Climatic conditions and character of date crop at Tozer, 1901 to 1905. Year. Sum of means, May to October. Sum of maxima, May to October. Rainfall, May to October. Character of crop. 1901 1902 1903 1904 1905 3,459 3,899 3,309 3,719 3,565 5,335 5,922 5,793 5,622 5,643 May 0.87 Yield not stated. Quality lowered by September rains, especially inferior sorts, which contained many worms. Crop very large, but quality somewhat injured by autumn rains. Crop much smaller than in 1904. Crop very large and of excellent quality. Harvest retarded until October 23-26. Dates ripened imperfectly. June July August September . October.... May 1.07 .84 2.78 June . . July .... August September. October .... May .... 0.64 1.78 2.42 June .. July August September. October 0.9H May .93 June July August September. October.... (May 0.08 .13 .13 .34 0.17 .75 .11 June ... July . August September. October.... .40 1.43 Judging by the data for 1904, the period of the writer's visit, when the crop was admitted on all sides to be an unusually fine one, both as to the quality and quantity of the fruit, it would seem 92 26 DATE VARIETIES AND DATE CULTURE IN TUNIS. as if the sum of the daily means, which in 1904 was more than 150 degrees higher than the normal, were a more satisfactory basis for comparing one season with another at the same locality than the sum of the daily maxima, which was about 200 degrees lower than the normal. Furthermore, in 1905, when the ripening of the dates was late and imperfect, the sum of the daily means was nearly nor- mal, while that of the daily maxima was again nearly 200 degrees lower than the normal. In 1903, w T hen the crop was much smaller than in 1904, the sum of the daily maxima was only 25 degrees lower than the normal, while the sum of the daily means was nearly 250 degrees below the normal. Still more conclusive are the data for 1902, a year when the crop was unusually large. The sum of the daily maxima of that season was only 100 degrees higher, while that of the daily means was 350 degrees higher than the normal. TABLE 5. Mean maximum and minimum temperatures at Tozer during the months of May to October, 1904 and 1905. Year. May. June. July. August. September. October. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. Max. Min. 1904... 90.3 89.4 65.3 63.5 89.2 98.2 75.7 72.7 104.7 105.0 85.4 80.0 108.7 104.3 84.4 79.7 96.2 97.3 73.7 75.9 83.1 78.6 61.3 62.8 1905 Comparing further the good year 1904 with the poor year 1905 at Tozer, we find that while the mean maximum was much higher in June and slightly higher in July in the latter year, the August and October maxima were considerably higher in 1904, while those for May and September differed little in the two years. The mean minima during the first four months of the season were considerably higher in 1904 than in 1905. ATMOSPHERIC HUMIDITY. The amount of moisture in the air is an important factor in date culture. At Gabes, in Tunis, one of the few localities in the world where the date palm is extensively grown on the seacoast, the qual- ity of the fruit is often seriously impaired by this cause (see p. 19). In the following table the mean relative humidity for each of the four seasons and for the year is given for several localities in North Africa, where date culture exists, and for localities in the south- western United States, where it can probably be successfully intro- duced. 92 PRECIPITATION. 27 TABLE 6. Mean relative humidity at localities in the desert regions of Tunis, Algeria, and the United States. Season." Tunis. Algeria. United States. Tozer. Gabes. Gafsa. Biskra. Ouargla. Yuma. Winter Per cent. 70.6 63.0 52.0 59.6 Per cent. 70.1 65.0 64.1 67.6 Per cent. 64.0 57.6 47.0 59.6 Per cent. 59.8 47.7 34.9 51.3 Per cent. 48.5 46.4 30.1 47.6 Per cent. 46.9 38.3 41.7 44.7 Spring . Summer Autumn. Year 61.3 66.7 57.0 48.4 43.1 42.9 Winter comprises December, January, and February ; spring, March, April, and May ; summer, June, July, and August ; and autumn, September, October, and November^ As shown by the above table, the Tunis oases have at all seasons a decidedly more humid atmosphere than those of Algeria. At Yuma the air is drier than at any of the North African localities, except in summer, when Yuma is more humid than Biskra and Ouargla. Comparing the three Tunis localities one with another, we find that at most seasons the humidity is greatest at Gabes, as would be expected from its situation on the coast, and least at Gafsa, which lies in the midst of extremely arid elevated plains and is cut off from the sea by ranges of desert mountains. Tozer in winter is slightly more and in spring little less humid than Gabes, but in summer and autumn it is decidedly drier. All things considered, the humidity at Tozer is surprisingly higher for a locality where the finest kinds of dates are produced. PRECIPITATION. TABLE 7. Normal precipitation, in inches, at localities in the desert regions of Tunis, Algeria, and the United States. Season. Tunis. Algeria. United States. Tozer. Nefta. Gabes. Gafsa. Biskra. Tou- gourt. Ouar- gla. Phoe- nix, Ariz. Yuma, Ariz. Volcano Springs, Gal. Winter 1.7 2.4 0.1 0.7 1.4 2.1 0.2 0.7 2.8 1.9 0.1 2.7 2.4 3.4 0.6 1.9 2.1 2.2 0.6 1.8 2.0 1.6 0.1 1.3 1.4 1.4 0.1 0.7 2.3 1.0 2.0 1.5 1.3 0.4 0.5 0.6 1.1 o.i 0.2 0.2 Spring Summer Autumn. Year 4.9 4.4 7.5 8.3 6.7 5.0 3.6 6.9 2.8 1.6 The total annual rainfall of the Jerid oases (Tozer and Nefta) is very much less than that of Gabes, on the coast of Tunis, and of Gafsa, which has an elevation of 1,000 feet above sea level. Tozer The relation of the rainfall of the Tunis oases to date production is dis- cussed under the heading " Ripening," on pp. 51 and 52 of this bulletin. 92 28 DATE VARIETIES AND DATE CULTURE IN TUNIS. has about the same total precipitation as Tougourt, in Algeria, con- siderably more than Ouargla, Algeria, and considerably less than Biskra, Algeria, and Phoenix, Ariz., the last two localities having nearly the same total. The Colorado River Valley and the Salton Basin in the United States receive considerably less rain than any of these North African localities. Regarding the distribution by sea- sons, we find that nearly one-half of the total precipitation falls in spring in the Jerid oases, a larger proportion than at any of the other localities given in the table. The autumnal precipitation is relatively smaller at Tozer and at Nefta than at any of the other localities excepting Volcano Springs, Cal. At Phoenix and Yuma, Ariz., the rainfall in summer forms a much higher proportion of the total for the year than at any of the other points included in the table. IRRIGATION AND DRAINAGE. As the water supply and irrigation conditions of the oases of the Nefzaoua, Gabes, and Gafsa have been briefly discussed under the heading " Geography," only the Jerid region will be treated in this place. WATER SUPPLY. The oases of the Jerid, unlike those of the Oued Rlrh, in Algeria, are watered by means of springs instead of wells. This is explained by the fact that the Jerid oases are situated at the very base of the terrace that marks the northern frontier of the desert, while the Oued Rirh group lies well into the Sahara. Attempts to obtain artesian water in the Jerid region have so far been unsuccessful. The springs of the Jerid are all situated at about the same eleva- tion 135 to 150 feet above sea level. They originate in strata of cretaceous formation at the base of the line of bluffs. As the springs are very numerous and in many cases very large, maintaining a prac- tically constant flow throughout the year, it seems unlikely that the scanty rainfall of the region itself can account for the abundance of the water supply. 6 The general temperature of the water as it issues from the ground is about 86 F., and varies little from season to season. a See Bui. 53, Bureau of Plant Industry, U. S. Dept. of Agriculture, pp. 44-40, where the irrigation of the date palm in the Algerian Sahara is described ; also, Bui. 80, Bureau of Plant Industry, pp. 36-38, where this subject is discussed. 6 Holland, Hydrologie du Sahara Algerien, pp. 182, 183, holds that the water which feeds the springs of the Jerid must constitute an artesian sheet, derived largely from the eastern spurs of the Aures Mountains and flowing deep under the elevated plain which abuts on the shotts of southern Tunis. On the other hand, Doumet-Adanson (Sur le regime des eaux qui alimentent les oasis du Sud 92 WATER SUPPLY. 29 The oasis of Nefta is supplied with water by a large number of springs that arise in the " Corbeille," or "basket" (p. 15). Their combined flow, amounting to about 292 gallons (1,100 liters) per sec- ond, gives rise to the stream which waters the southern part of the oasis. This quantity of water is estimated by Rolland to be sufficient for irrigating the entire oasis at the rate of about 2 acre-feet per acre annually. Taking as the number of date palms existing at Nefta the mean of the two estimates given on page 15, we should have 282,500 trees. If the total supply furnished by the springs were divided equally among them, each would receive about 0.24 quart per minute, or about 86 gallons per day. As it has been calculated by Holland that to give the best results each date palm should be allotted at the source of sup- ply 0.53 quart (0.5 liter) per minute (hence about 190 gallons per day) 6 it is evident that the supply available is not sufficient for the perfect irrigation of more than one-half of the date palms of the oasis. The 140 springs that supply the oasis of Tozer with irrigating water give rise to a stream that delivers about 278 gallons (1^050 liters) per second; hence about 3,200,000 cubic feet daily. This quantity is estimated to suffice for irrigating the oasis at the rate of about 1.5 acre- feet per acre annually. Assuming that there are 385,500 palms (the mean of the two estimates given on page 16) in this oasis, and making the calculation upon the same basis as for Nefta, the share of water at the source of supply available for each tree would be only 0.17 quart per minute, or 62.4 gallons per day, which is less than one-third the amount (0.53 quart per minute) esti- mated by Holland as the optimum. It should be noted, however, that the distribution of water among the different parts of the oasis is very de la Tunisie, Assoc. Frang. Avancem. Sciences, 1884, p. 72) regards the infil- tration water drained through the sands of the adjacent region as sufficient to supply these springs. He does not consider the water sheet to be of artesian character. a Holland, assuming that there were 201,100 palms at Nefta, calculated that there should be available for each, at the source of supply, 0.33 liter (0.35 quart) per minute. In his, as in the writer's calculation, no deduction is made for the amount of water lost to the palms through seepage and evaporation from the ditches, growing of other crops, and use by the inhabitants and their domestic animals. & See Bui. 53, Bureau of Plant Industry, p. 45. c A much lower estimate has been made by M. Minangoin, inspector of agri- culture at Tunis, of the amount of water theoretically available for each date palm in the oasis of Tozer. He states that the combined flow of the 140 springs is only 1,700,000 (instead of 3,200,000) cubic feet daily; and assuming that there are 300,000 trees in the oasis, he arrives at the figure of 42 gallons (160 liters) as representing the amount available at the source of supply for each palm daily. 92 30 DATE VARIETIES AND DATE CULTURE IN TUNIS. unequal, the palms in some gardens being amply and even super- abundantly irrigated, while thousands of trees receive no irrigation whatever, except by seepage. There is some indication that the flow of the springs at Tozer is diminishing in volume. It would appear also that there has been a gradual lowering of their level, due to the progressive cutting down of the beds of the streams derived from them, and that in consequence the irrigable area of the oasis is diminishing. 6 In the oasis, or oasis group, of El Oudiane 60 springs furnish the water with which the gardens are irrigated. They are generally smaller than those of Nefta and Tozer, and their flow is said to be perceptibly diminishing. Their waters are not united to form a large stream which is subsequently divided and subdivided by dams, as in the oases just described, but are for the most part conducted directly to the gardens. These, owing to the small width of the oasis and its situation at the very foot of the terrace, are nowhere far removed from the sources of supply. At El Hamma there are 15 springs of considerable size, one of them having a temperature of 107.5 F. (42 C.). To this spring, which is much frequented by the natives for the sake of the hot baths it affords, the oasis owes its name, which means " the bath." A sample of irrigating water was collected by the writer in the main stream of Tozer, above the first dam which divides it. This water, tested both at the moment of collection and two months later, when the analysis was made, gave neither an alkaline nor an acid reaction. Its electrical resistance at the time when the sample was taken was 117.3 ohms at 60 F. The chemical analysis, made in the laboratory of the Bureau of Soils, showed 209.2 parts of soluble matter per 100,000 of water. The composition of the soluble con- tents was as follows, in percentages of the total : TABLE 8. Chemical composition of irrigation water, Tozer oasis. Components (ions). Conventional combinations. Calcium 8.50 Calcium sulphate 28.87 Magnesium 4.54 Magnesium sulphate 17.36 Sodium 9 13 Potassium chlorid 23 47 Potassium 12.34 Magnesium chlorid 4.11 Sulphions 34 23 Sodium chlorid 16.68 Chlorions 24 33 Sodium bicarbonate 9 51 Carbonic acid 6 33 100 00 100.00 o At Biskra, in Algeria, 0.12 quart per palm per minute is found to give satis- factory results, the water being retained at the bases of the trees in holes that are dug for the purpose. (See Bui. 53, Bureau of Plant Industry, p. 47.) 6 Doumet-Adanson (ibid.) noticed old date palms at Tozer that could no longer be irrigated, being no less than 40 feet above the present level of the springs. 92 IRRIGATION SYSTEM. 31 It is evident from this analysis that the water afforded by the springs of Tozer is pure enough to be used with perfect safety in irrigating any crop grown there. As the springs of the other oases of the Jerid have a similar origin to those of Tozer, it is probable that the composition of their waters differs little from the foregoing. IRRIGATION SYSTEM. Irrigation at Tozer has been brought to a higher stage of develop- ment than elsewhere in the Jerid, and a description of the system in use at Tozer will serve for the other oases as w T ell. a It is said to have been elaborated long ago by an Arab named Ben Chabet, and to have been religiously maintained, unchanged as he planned it, to this day. FIG. 2. Irrigation canal and diversion dam, Tozer oasis. The details of its management are transmitted from father to son in a certain family. Having perfected the system at Tozer, Ben Chabet offered to do the same service for the inhabitants of Nefta, who were constantly in dispute over their water rights, but their jealousy of Tozer prevented their accepting his offer. "French students of the Tozer system praise very highly the ingenuity and thoroughness with which it has been worked out. The main stream which collects the waters of all the springs of Tozer is divided and subdivided by a series of dams made of palm logs (fig. 2) until the water reaches the ultimate divisions or seguias (ditches) which supply each individual garden. The log which For a detailed account of this system, see F. Masselot, " Les Dattiers des Oasis du Djerid," Bui. Dir. Agr. et Com. Tunis, 1901, pp. 137-142. 92 32 DATE VAKIETIES AND DATE CULTURE IN TUNIS. is laid across the canal to form the dam is divided into a series of long, shallow notches, separated by narrow ridges. The number of notches in each dam corresponds to the number of parts into which the stream is to be divided at that point. Thus, if three-fifths of the water is to be diverted into one of two branches and two-fifths into the other, five notches are cut, the water passing over three of them going to the first branch and the rest to the second. The notches being all of the same length and depth, the division is quite accurate. Divisions of the main stream down to the twenty-first part of the total flow are not transferable, belonging for all time to the same district of the oasis. Smaller fractions of the water, however, can be alienated, and there is much bartering of water rights among the different proprietors of gardens. At all the principal diversion dams, guards are stationed day and night to prevent any tampering with the water, there being three guards at the first diversion and two at each of the other important ones. These guards are paid with a bunch of Fteemy dates from each garden that receives water passing over the dam they tend, those at the first diversion being entitled to a bunch from every garden in the oasis. The " amin," or expert, who supervises the entire system has also the right to select a bunch of Fteemy dates fr6m every garden, his being the first choice after the " khammes," or tenant, of the garden. The principal canals are kept up by assessment upon all the owners of gardens supplied by them. Smaller ditches (seguias) must be kept in order by the tenants of the gardens served by them, and it is also the duty of the khammes (tenant) to be on hand at the small dam which diverts water into his ditch when it is the turn of his garden to receive water, for there is a fixed hour for the irrigation of each garden. The method of measuring time in connection with this irrigation system is an interesting one. A metal cup-like receptacle, called a " gadous," is filled with water and hung up in a convenient place by the dam. The bottom of the receptacle is perforated, and the hole is always of the exact size necessary to let all the water run out in just five minutes. The water that runs over a notch in the dam during the time required for the gadous to empty eleven times (hence, in fifty-five minutes) is sufficient to irrigate thoroughly a garden of 2.4 acres (1 hectare), the length of the notch being fixed and its depth corresponding to the velocity of the current. a The " amins " (pronounced " ameens ") are selected from among the older in- habitants of the community for their knowledge of agricultural matters. Their function is to act as arbiters in disputes concerning water rights, the rela- tions between proprietors and tenants, the sale of agricultural products, etc. 92 TEXTURE OF SOILS. 33 The gardens are divided into small plots by means of banks of earth, to facilitate irrigation, as in the basin method used in the United States. The water from the ditch (seguia) is turned into the nearest plot through a breach made in its bank, the ditch being dammed at that point with a few spadefuls of earth. When the soil is sufficiently saturated, the farther bank is cut, allowing the water to pass on into the plot beyond ; and so on, until the whole garden has been irrigated. In this way not only the date palms, but the other fruit trees and the small crops among them that occupy a portion of every garden, are irrigated simultaneously. DRAINAGE SYSTEM. Owing to the situation of the oases on the edge of the Shott Jerid and the great amount of water used in irrigation, its soils would be completely water-logged were it not for the excellent provision that has been made for drainage. Each garden is provided with open drainage ditches, or " khandaks," these being generally about 166 feet apart and about 5 feet deep. They are constructed at the ex- pense of the proprietor of the garden, the work of keeping them open devolving upon his tenant. Several of these smaller drains unite to form a large ditch, which is kept up by an association of the proprietors whose gardens are served by it, each contributing in proportion to the size of his water right. Finally, at Tozer. all the drainage ditches empty into a main one called the " Khandak-el- Kebir." which runs along the southern side of the oasis and carries its drainage water to the Shott Jerid. In former times, when Tozer was frequently raided by the savage nomadic tribes of the desert, this large drainage ditch also served the inhabitants as a moat for the defense of the oasis. Not only is this excellent drainage system useful for ridding the oasis of surplus water, but it renders inesti- mable service in preventing the harmful accumulation of salts or "alkali." (See p. 36.) SOILS OF THE JERID REGION. TEXTURE. As the soils of the Jerid region only were investigated, the discus- sion which follows relates only to that group of oases. All samples for analysis were collected at Tozer, but the composition of the soils of the other three oases is probably similar, except that those of Nefta apparently contain a higher percentage of sand. The date palm is said to grow most rapidly and vigorously in the soils that are richest in clay, although yielding a better quality of fruit in the sandier soils. 30618 No. 9206 3 DATE VARIETIES AND DATE CULTURE IN TUNIS. The following table gives the results of mechanical analyses of the samples taken, as furnished by the Bureau of Soils. Descriptions of the localities where each sample was obtained will be found in Table 11, on page 37, under corresponding numbers. TABLE 9. Mechanical analyses of soils of Tozer oasis. a a a 1 fi o 3 a 3 r- 1 d a rH 3 o a H Num- ber of Depth of Character of soil. 3 S d li d O pi?" sample. "> " $& 3 g 6 1 a fl 3 d 8 d o'