Citrus fruits; an account of the citrus fruit industry, with special reference to California requirements and practices and similar conditions

Front matter

CITR

F..R.U.I IS t;

ciencG Series

Preface

The citrus industry has now reached a high state of development in both California and Florida. Furthermore, it is progressing with rapid strides. Old World practices and precedents have been largely ignored in the development of an industry characteristically American in spirit and new in methods. The readiness with which the growers adopt new and better methods is an indication of the virility and youthful vigor of this new industry.

The literature has hardly kept pace with the industry and is scattered through a large number of periodicals and reports. On this account, it is largely unavailable to those who need it most. The last comprehensive work published in California was that of Lelong in 1902. This quickly ran out of print and for the last six years lias been rare.

The present volume represents an attempt to discuss underlying principles in such a way as to emphasize the importance of certain stable fundamentals upon which the rapidly changing superstructure is built. It has also been the aim to describe the industry as it exists to-day, and bring together in orderly arrangement all the information available at this time which is worth while.

vi Preface

The author has enjoyed the cooperation and assistance of many friends. The chapter on History and Development has been read and criticised by J. M. Guinn of Los Angeles. Professors E. J. Wickson, E. B. Babcock, B. A. Etcheverry, W. T. Home, and H. J. Qaayle, together with Messrs. W. S. Reed and E. O. Essig, have kindly read and criticised parts of the manuscript. E. G. Dezell of the California Fruit Growers' Exchange read the chapter on Marketing. I am indebted to my co-worker, I. J. Condit, for contributing parts of the chapters on insects and fumigation. For cordial cooperation in taking the atmometer records reported on in Chapter XII, I am under obligation to W. M. Mertz of the Citrus Experiment Station. Some historical and other data Uwsed in Chapter 'XIV on "Frosts and Orchard Heating " lias been taken from the excellent graduating thesis of Carl Nichols.

For the use of certain illustrations I am indebted as follows: to Carl Nichols for Nos. 10, 14, 15, 64, 65, and 86; to W. I. Jones for Nos. 57 and 58; to the Roeding & Wood Nursery Company for Nos. 110, 111, & 110 ; to L. H. Moore for Nos. 113 and 120 ; to Professor H. S. . Fawcett for No. 128 ; to professor H. J. Quayle for Nos. 139, 141, 142, 143, 144, 145, and 147; and to Professor C. W. Wood worth for No. 151.

J. ELIOT COIT.

Berkeley, California, February 17, 1915.

Chapter I Pages

History and Development ...... 1-24

First planting of orange seeds in California, 1 — first . commercial orchard, 2 — other pioneer plantings, 3 — early citrus fairs, 5 — the panic of 1884-1886, 6 — the cottony cushion scale, organization of cooperative marketing, 8 — California citrus shipments, 9 — other factors which have made for progress, 10 — history of the Washington Navel orange, 13 — the citrus industry in Arizona and Sonora, 23

CHAPTER II Geography and Climatology of California . . . 25-39

Classification of citrus areas, 26 — southern coast, 28 — interior valley, 80 — northern coast, 31 — the frost hazard, 33 — atmospheric humidity, 34 — winds, 36 — sunlight, 38

CHAPTER 111

Botany, Gross Structure, and Habits or Growth . 40-64

Classification, 42 — conspectus, 43 — structure of the citrus plant, 45 — roots, 45 — wood, 46 — leaves, 49 — thorns, 51 — flowers, 52 — pollination and seed formation, 55 — polyembryony, 59 — structure and composition of the fruit, (50 — seasons of blossoming and harvest, 63 — longevity, 64

vii viii Contents

Chapter IV Pages

Seedling trees no longer planted, 65 — the struggle between many varieties, 65 — the survivors few in number, 66 — the orange, description of varieties, 66 — the lemon, description of varieties, 72 — the pomelo, description of varieties, 75 — the mandarin, description of varieties, 78 — the Swingle- Webber hybrids, description of varieties, 79 — the citron, 80 — the shaddock, 81 — the lime, 81 — the kuraquat, 83 — the sweet lemon, 83 — the trifoliata, 83

Chapter V

The seed-bed, 84 — source and cost of seed, 86 — preparation and planting of seed-bed, 87 — eradication of scale from nursery trees, 90 — planting seed-bed stock, 91 — propagation, 92 — cutting bud- wood, 93 — storing bud-wood, 94 — time of budding, 95 — method of budding, 95 — training the nursery tree, 100 — balling and shipping, 102

CHAPTER VI HoRTTrULTURAL INSPECTION AND QUARANTINE SERVICE . 106-113

The California State Commission of Horticulture, 106 — inspection of interstate shipments, 107 — quarantine orders, 109 — State Fruit Growers' Conventions, 109 — the County Commissioners of Horticulture, 1 10 — duties of county commissioners, 110 — compulsory fumigation, 110 — the necessity for inspection. 111

CHAPTER VII Improvement ok Citrus Fruits by Breeding . . . 114-131

Hybridization, 115 — structure of citrus flower, 1 15 — cross-pollination, 116 — improvements most needed, 118

Conienis ix

— vecjetativo mutations or bud-sports, 118 — kinds of variations, 110 — fluctuations, 115) — mutations, 120 — sectorial chimeras or mixed plants, 121 — performance records needed, 124 — record of West Highland (irove, 126 — selection of bud-wood, 128 — pedigreed stock, l.'JO

CHAPTER VIII Ji;i)GixG Citrus Fruits ....... 182-188

Orange score-card, 133 — orange standards, 133 — lemon score-card, 184 — lemon standards, 135 — pomelo .score-card, 180 — pomelo standards, 136 — packed box score-card, 137 — packed box standards, 137 — exhibit score-card, 138

Chapter IX

Selection of Site and Preparation for Planting . 139-140 Selection of site, 139 — score-card for citrus lands, 139

— the frost question, 140 — water supply, 141 — soil adaptations, 142 — clearing and leveling land, 145 — amelioration of hardpan by the use of dynamite, 146

CHAPTER X Planting the Orchard ....... 147-164

Orchard plans, 147 — number of trees per acre, 149 — distance of planting, 149 — contour planting, 151 — time of planting, 151 — root-stocks, 151 — digging the holes, 155 — setting the trees, 156 — intercropping, 159 — the cost of planting, 160

CHAPTER XI Cultivation, Fertilization, Cover-crops . . . 165-186

Plowing, 165 — cultivating, 168 — mulching, 173 — orchard tractors, 174 — fertilizing, 175 — humus, 178 — green manure crops, 181 — summary of soil management, 184

Contents

CHAPTER XII Irrigation

Amount of water needed, 188 — atmometer records, 189 — sources and cost of water, 192 — methods of distribution, 193 — time of application, 195 — methods of application, 198

CHAPTER XIII Pruning and Topworking

Pruning trees in the nursery row, 205 — pruning oranges, 207 — suckers versus fruit wood, 209 — pruning lemons, 213 — disposition of prunings, 217 — pruning frosted trees, 217 — reheading young trees, 218 — reheading mature trees, 220 — topworking old trees, 223 — pruning tools, 225 — wounds and dressings, 226

PAGES

187-203

204-229

Chapter XIV

Historical cold periods, 230 — season of frost in California, 231 — forecasting frosts, 233 — factors influencing the occurrence of frost, 234 — local conditions affecting frost, 236 — conditions indicating frost in California, 237 — how plants are injured by cold, 239 — prevention of frost injury, 243 — orchard heating with oil, 252 — requirements of orchard heaters, 253 — types of oil heaters, 257 — installation of heaters, 259 — properties of fuel oils, 260 — storage for oil, 262 — oil heating operations, 264 — care of heaters, 267 — cost of oil heating, 268 — separation of frosted from sound fruit, 270 — cooperation in frost fighting, 274

230-276

CHAPTER XV Picking and Packing Oranges

Importance of careful handling, 277 — causes of decays, 278 — clippers, 279 — picking bags, 280 — methods of

277-301

Contents xi picking, 281 — the sweating of green fruit, 285 — the acid-sugar ratio, 289 — brushing and washing, 21)1 — grading and sizing, 292 — packing and loading, 295 — precooling, 297 — shipping, 298

CHAPTER XVI Picking and Packing Lemons ...... 302-317

Season of maturity, 303 — market, demands, 302 — sweating autumn lemons, 305 — storage of winter lemons, 306 — packing and shipping, 309 — grading and sizing, 310 — picking pomelos and tangerines, 312 — packing-houses, 314

chaptp:r XVII

Blemishes of the Fruit and theiu Prevention . . 318-330

Insect blemishes, 319 — fungus blemishes, 319 — mechanical blemishes, 321 — bruises, 321 — thorn-stabs, 321 — cultivator vscars, 321 — clipper cuts, 321 — stem punctures, 321 — machine injuries, 322 — fumigation scars, 322 — shoulder spots, 323 — hail scars, 323 — soil scars, 323 — windfalls, 324 — cement dust, 324 — physiological blemishes, 324 — sunburn, 324 — frost, 325 — off-bloom, 325 — mottled-leaf, 325 — exanthema, 325 — malformations, 326 — brown spot, 326 — splits and cracks, 326 — puffing, 329 — peteca, 329 — diy center of lemon, 329

CHAPTER XVIII By-products .... .... 331-343 United States importations of citrus by-products, 332

— commercial by-products, 333 — citric acid, 333 — lemon and other oils, 334 — uiifennented orange juice, 38.",

— orange vinegar, 336 — orange wine, 337 — candied citron, 337— oil of neroli, 338 — petit grain oil, 338 — xii Contents

PAGES

tincture of orange flowers, 338 — essence of orange flowers, 338 — dried and candied peel, 339 — lime juice, 339 — orange paste, 340 — crystallized baby oranges, 340

— glacedkumquats,341 — domestic recipes, 341 — orange or lemon jelly, 341 — orange marmalade, 342 — pomelo marmalade, 342 — citrus-rhubarb marmalade, 343

CHAPTER XIX Markkting 344-354

Methods of selling fruit, 344 — independent growers, 344 — independent associations, 345 — California Fruit Growers' Exchange, 345 — the local association, 346 — the district exchange, 347 — the central exchange, 348 — collecting and handling money, 350 — exchange advertising, 351 — method of organizing cooperation associations, 351 — Florida Citrus Exchange, 353 — Citrus Protective League of California, 353

CHAPTER XX Profit and Loss 355-363

Average returns, 355 — over-capitalization, 356 — eight requirements for success, 357 — capital recjuired, 358 — cultural costs itemized, 361 —average yields, 362

— average prices received, 362 —judging orchards and lands, 362 — score-card for citrus land, 363

CHAPTER XXI Diseases and theik Control ...... 364-402 Brown rot gum disease, 364 — botrytis gumming, 366

— .scaly-bark, 367 — twig gumming, 367 — leaf gumming, 3(}8 — gumming of seed-bed stock, 368 — exanthema or die-back, ^M) — mal-di-gomma or foot-rot, 372 — toadstool root-rot, 373 — mottled-leaf, 374 — wither-tip, 380

Contents

XI 11

— twig l)light, 382 — cottony mold, 388 — brown rot fruit decay, 386 — blue mold and green mold, 387 — gray mold, 388 — black rot of Navel orange, 388 — brown spot, 389 — damping off, 391 — citrus canker, 392 — melanose and stem end rot, 394 — nail-head rust, 395 — scab or verrucosis, 395 — diplodia rot of oranges, 397

— red blotch of lemon, 398 — yellow spotting of oranges, ;]98 — stem end spot, 399 — trunk rot, 399 — galls and knots, 401 — black pit of lemons, 401

CHAPTER XXII Citrus Insects and thkir Control ..... 403-430

Black scale, 405 — red or orange scale, 411 — yellowscale, 414 — purple scale, 414 — cottony cushion scale, 417 — soft brown scale, 418 — citricola scale, 419 — hemispherical scale, 420 — greedy scale, 420 — oleander scale, 420 — citrus mealy bug, 421 — citrus red spiders, 423 — silver mite, 424; — orange thrips, 425 — aphis or plant louse, 427 — orange tortrix, 428 — Fuller's rose beetle, 429 — western twelve-spotted cucumber beetle, 430

CHAPTER XXIII Insect Control by Fumigation ..... 431-452

History of fumigation, 431 — fumigation by hydrocyanic acid gas, 435 — tents, 435 — equipment of tents, 437 — generators, 437 — cyanide, 438 — acid, 439 — operation, 440 — season of fumigation, 443 — dosages, 449 — dosage schedule for sodium cyanide, 446 — new Woodworth dosage table, 450 — cost of fumigation, 452

CHAPTER XXIV Various Orchard Pests and their Control

Citrus nematode, 453 — the pocket gopher, 456 ground squirrels, 458 — poisons, 459

453-459 xiv Contents

Chapter XXV

Other bibliographies, 461 — references to literature dealing with particular fruits, 461 — orange growing in United States, 461 — growing in other countries, 463 — varieties, 464 — breeding, 467 — insects, 467 — diseases, 468 — lemon, 469 — lime, 471 — mandarin, 471 — pomelo, 472 — kumquat, 471 — citron, 473 — references to literature dealing with citrus fruits in general, 473 — miscellaneous references, 473 — propagation, stocks, scions, 478 — breeding, 479 — soils, roots, 481 — irrigation, 482 — ^fertilization, 483 — cover-crops and green manuring, 484 — varieties, botany, 485 — chemistry, judging, 486 — pruning, 487 — curing, storing, sweating, packing, 489 — marketing, organization, statistics, tariff, 490 — by-products, 492 — frost fighting, frost injured fruit, 494 — insect pests, 496 — fumigation, 497 — diseases, 499

LIST OF ILLUSTRATIONS

Washington Navel ()ran2;e ...... Frontispiece

km;. l'A<iK

1. Thomas A, Garey, a pioneer citrus nurseryman ... 4

2. The passing of the old seedling orange groves . . .12 o. Mrs. L. C. Tibbet, who first brought the true Navel orange

to California ......... 18

4. One of the two original Washington Navel orange trees

brought to California . * . . . . . .21

5. California citrus areas ........ 27

6. Four-year-old Valencia orange grove in Los Angeles County 28

7. Typical scene in Los Angeles County. Windbreak of Gre-

villea rohusta on right ....... 35

8. Pinus radiata, a native pine, used as a windbreak . . 36

9. Orange tree denuded of foliage on windward side by three

days of desert \vind . . . . . . .37

10. Growth rings in a flattened brace-limb of lemon ... 47

11. Result of experiment which shows that a girdled orange tree

may grow new bark. A. Untreated ; B. Treated . 48

12. Valencia orange blossoms 53

13. Lemon blossoms showing perfect, partly aborted and aborted

pistils. Stamens removed in latter case ... 54

14. Orange flower x 2. p, pistil ; a. stigma ; c, style ; o, ovary ;

s, stamen ; h, anther ; e, filament ; d, nectary ; g, sepal ;

/, petal 57

15. Polyembryony. Two orange seedlings from one seed . . 60

16. The earliest known illustration of a Navel orange. From

Ferrarius' " Hesperides," 1646 67

17. One type of Australian Navel orange 69

18. Eureka lemon, uncured ....... 73

19. Lisbon lemon, uncured 75

XV

XVI

List of Illustrations

FIG.

20. Seedless pomelo, flowers and fruit. From Volckamer's

" Hesperides," 1708

21. Dancy Mandarin orange

22. Satsuma Mandarin orange

23. Nagami kumquat .

24. Citrus seed-bed under lath

25. Citrus seed-bed in the open

26. Bench-rooted orange seedling

27. Orange bud-wood .

28. Cutting a bud

29. Making incision in stock

30. Inserting bud

31. Tying inserted bud

32. Orange buds in nursery row tied to lath stakes

33. Healing of the bud union

34. Balling orange trees in the nursery

35. A shipment of defoliated balled orange trees

36. Two-year-old orange trees, balled, ready for market

37. Type of standard Washington Navel orange .

38. Washington Navel oranges showing fluctuations in the navel

Such variations cannot be preserved by budding

39. Variegated sport. Note white areas in leaves. From Volck

amer's " Hesperides," 1695 .

40. A variegated sport of Valencia orange. Notice white margin

of leaves , . . . .

41. Sectorial chimera of Valencia orange

42. Orange showing sectorial chimera. From Ferrarlus' " Hes-

perides," 1646

43. What is known as the "Wrinkled" sport of Eureka lemon

compared with normal fruit. Both from same tree

44. Chart showing by dotted line the small proportion of profit-

able trees, and by heavy line the large proportion of trees which only pay for their care. West Highlands Orchard, (Adapted from Norton) . . . .

45. Cow peas as an intercrop in young lemon orchard

46. Breaking a layer of hardpan by means of a stick of dynamite

discharged in each tree hole

122 124

129 153

Lid of Illu.slrdfloihs' x\ii

KIO. VM.r.

47. Newly set tree properly protected from sun . . . .158

48. Cultivating newly set orange trees with eight-chisel cultivator HHi

49. Cloddy condition due to land being worked while too wet . 1()7

50. Ground under trees worked with ease by means of orchard

tractor 169

51. Orchard tractor doing the work of eight mules in a hot

desert valley 171

52. Heavy plowing with an orchard tractor of the caterpillar

type 173

53. Substituting baled lima bean straw for manure in lemon

orchard near Whittier, California . . , . .176

54. Cull oranges used as a humus-forming fertilizer . . . 180

55. Canal lined with cement. Transformation of desert hills

into orange groves 187

56. Preparing the ground for furrow irrigation. (From U. S.

D. A. Farmers' Bui. No. 404) 190

57. Irrigating stands in operation . . . . . .194

58. Zigzag furrows for whetting the ground between the trees . 197.

59. Overhead irrigation system in old orange orchard near

Covina, California 199

60. King soil sampler. Of use when irrigating .... 202

61. A well pruned Eureka lemon orchard. Photographed,

August 10th, near Alhambra, California . . . 205

62. Prototype of California pruning saw. From Volckamer's

" Hesperides," 1708 207

63. " California " pruning saw, used throughout southwest . 208

64. Good type of pruning saw above ; poor type below . .210

65. One of the best types of pruning shears . . . .211

66. Vigorous fruiting brush growing in the place of suckers . 212

67. This extra vigorous shoot terminated at six inches with a

fruit showing that excess of food did not change it into

68. A .sixty-acre three-year-old Valencia orchard top-worked to

lemons. The pajier bags protect the buds from rose

beetles 215

69. Fifteen months' growth on stocks shown at Fig. 68 . . 21(5

70. 'I'll ree-y ear-old Navel head on top-worked sweet seedling . 221

XVlll

List of Illustrations

FIG.

71. Pruning a frosted lemon orchard .....

72. A. Normal vesicles of lemon. B. Enlarged vesicles from

frosted fruit six months after injury

73. Frost splitting of bark on fruiting brush of lemon

74. Three-year-old trees protected v^ith cornstalks .

75. Screen of tobacco cloth as a frost protection

76. Big six .

77. Eichhoff coal burner .

78. Hamilton down-draught

81. Pomona pipe-line heater

83. Canco .

84. Kayo .

85. Hislop .

86. Hamilton reservoir

87. Troutman .

88. Adamson torch .

89. Coal-burning orchard heaters. Fuel stored in boxes under

trees .....

90. Orchard heaters ready for lighting

91. Orchard heaters in old Valencia grove

92. Placement of orchard heaters. Extra fuel in cans under

trees

93. The perforated stack gives good combustion but may admit

rainwater ....

94. The water separator for frosted fruit

95. Thermometer station of the Pomona Valley Orchard Pro-

tective Association

96. Tuttle fruit clippers with rounded points

97. Dashboard picking bag

98. Covina picking bag ...

99. Woodward picking bag ...

100. The Wiss clip])er now being sui)ersede(l

shown at Fig. 9(5 ....

101. Metal attachment for proi)])ing up limbs by the

^uttle

PAGE

261 262 263

266 271

275 279 280 281 282

283 283

Lid of Illn.slniflon.s

XIX via. rA<iK

102. Worm brushes used for polishiiii; oranges .... 284

103. Rope feed liopper 285

104. Orange sizing nKVchine ....... 280

105. Box press and nailing machin(! ...... 287

106. Citrus fruit truck .288

107. Tacking stand 280

108. Box-squeeze, small size ....... 200

109. Car-squeeze, large size . ' . . . . . .291

110. Interior view of the Pioneer Fruit Co.'s orange packing

house at Lindsay, California ..... 294

111. Orange packers at work . . . . . . . 290

112. A typical orange box label 299

113. General arrangement of orange packing house . . . 300

115. Two-story lemon packing house, Glendora, California . 304

116. Lemon washing machine and sorting table .... 307

117. Lemon curing tents in packing house near the coast . . 309

118. Truck for handling trays of ungraded lemons . . . 310

119. Packing lemons from sorting trays . . . . .311

120. Lemon packing house, second floor and elevation . . 314

121. Typical lemon box label ....... 315

122. Combination box label . . • . . . . . 316

124. Scar caused by rubbing on the ground .... 323

125. Orange splits. Side splits above and Navel end splits below 327

126. Horizontal cracks are very different from splits . . . 328

127. Peteca of lemon 329

128. The Fawcett method of treating gum disease. Note types

129. Reddish gum areas on under side of leaves caused by

130. Exanthema pustules on Valencia orange twigs . . . 370

131. Mottled-leaf disease on Eureka lemon .... 375

132. Advanced stage of mottled-leaf disease showing multiple

buds 377

133. Spot caused by wither-tip 380

134. A " nest " of cottony fungus 384

XX

List of Illustratiom

KIG.

135. Black rot of Navel

136. Brown spot of Navel orange . . , .

137. Stem-end spot of orange

138. Pruning stub on orange tree infected with schizophyll

139. Black scale on orange twig

140. The red scale on orange .....

141. Work of red scale on orange tree

142. The purple scale enlarged . .

143. Cottony cushion scale ......

144. Citrus mealy-bug

145. Scars due to citrus thrips

146. Fuller's rose beetle ......

147. The work of Fuller's rose beetle ....

148. Scars on rind of orange caused by katydid .

149. A fumigation demonstration .... 160. Method of marking fumigating tent 151. Flashlight picture of marked fumigating tents um

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