McGRAW-HILL PUBLICATIONS IN THE BOTANICAL SCIENCES EDMUND W. SINNOTT, CONSULTING EDITOR ECONOMIC BOTANY This book is produced in jutl compliance with the government's regulations Jor con­ serving paper and o.ther essential materials. SELECTED TITLES FROM McGRAW-HILL PUBLICATIONS IN THE BOTANICAL SCIENCES EDMUND W. SINNOTT, Consulting Editor Babcock and Clau8en-Genetics Lutman-Microbiology Belling-The Use of the Microscope Maximov--Plant Physiology Boysen Jensen-Growth Hormones Miller-Plant ~hysiology in Plants Pool-Flowers and Flowering Plants Braun-Blanquet and Fuller and Con­ Sass-Elements of Botanical Micro- ard-Plant Sociology technique Curtis-The Translocation of Solutes Seifriz-ProtoplasIll in Plants Sharp-Introduction to Cytology Eames-Morphology of Vascular Plants Sharp~Fundamentals ot Cytology Eames and MacDaniels-Plant Sinnott-Botany Anatomy Sinnott and Dunn-G.enetics Fitzpatrick-The Lower Fungi Smith-Cryptogamic Botany G(J,umann and Dodge-Comparative Vol. I, Algae and Fungi Morphology of Fungi Vol. II, Bryophytes and Haupt-An Introduction to Botany Pteridophytes Haupt-La1oratory Manual of Ele- Fresh-water Algae of the U. S. mentary Botany Swingle-Systematic Botany Hill-Economic Botany W eaver-Root Development of Field Hill, OverhoUs, and Popp--Botany Crops Microtechnique Weaver and Bruner-Root Develop. Johansen-Plant ment of Vegetable Crops Loomis and 'Shull-Methods in Plant Physiology Weaver and Clements-Plant Ecology Experiments in Plant Physiology W odehouse-Pollen Grains There are also the related series of McGraw-Hill Publications in the Zoologi­ cal Sciences, of which A. Franklin Shull is Consulting Editor, and in the Agricultural Sciences, of which Leon J. Cole is Consulting Editor. ECONOMIC BOTANY A Textbook of Useful Plants and Plant Products . BY ALBERT F. HILL Re8earch Assistant in Economic Botq.,,'11 . Harvard University . I . FIRST EDITION FIFTH IMPRESSION 'McGRAW-HILL BOOK COMPANY, INC. NEW YORK AND LONDON 1937 COPYRIGHT, 1937, BY THE MCGRAW-HILL BOOK COMPANY, INC. PRINTED IN THE UNITED "TATES OF AMERICA All rights reserved. This book, or parts thereof, may not be reproduced in any form without permission of the publil5hers. THE MApLE PRESS COMPANY, YORK, PA. PREFACE For some years past there has been an ever-increasing feeling among educators that the average college courses in elementary science have fallen far short of meeting the needs of the average student. For the most part such courses have been conducted on the supposition that their sole purpose was to lay the founda­ tion for further advanced work in their particular field. For the man who knows what he wants, this is essential. Many students, however, fall into other categories. Some take a first course because it is required; others to see whether or not they might become seriously interested in a subject; and still others out of idle curiosity or some less tangible reason. In such cases an elementary course should be so constituted as to be interesting and profitable to the extent of adding to the student':,; general fund of knowledge even if he does not continue in the field. In other words the course should have more of a cultural than a purely technical value. As Gager states it in the preface to his "General Botany," "A subject has cultural value in proportion to the number of human contacts it gives the pupil, the extent to which it broadens his views and extends his interests and sympathies." The field of applied science, dealing with the practical or economic aspects of a subject, lends itself much better to such treatment than does the field of pure science. This is particu­ larly true of botany. From earliest time plants 'have been intimately bound up with human existence. Not only have they played an important part in the everyday life of mankind, but they have had a profound influence on the course of history and civilization. A knowledge of the industrial, medicinal, and edible plants cannot fail to broaden one's outlook. Even though the value of including a considerable amount of economic material in a beginning course in botany may be recognized, the limitations of time or various curriculum require­ ment,., usually render such a procedure impracticable. It should be possible, however, to offer at lea,.,t a half-year cour,.,e devoted to economic plants as a supplement to the usual first year's v vi PREFACE work. Such a course would appeal to students in chemistry, economics, and other fields, as well as to those interested particu­ larly in plant science. Moreover, such a course in economic botany ought to be valuable to the science itself. Botany, more than any other science, has suffered from a lack of interest and appreciation on the part of the average person. Any attempt to educate the layman as to the importance of plants cannot fail to be productive of some beneficial results, and may help in establishing botany on a par with chemistry, physics, geology, and zoology in the eyes of the world. The present book is the outgrowth of several years' experience in presenting a one-semester course dealing with economic plants. The material utilized is 6f necessity limited, for the whole field of economic botany is too vast a subject, and only the surface can be scratched. An attempt has been made to include the most important plants of America and other parts of the world insofar aR they enter into international commerce. It has not seemed advisable to give the detailed morphology of -the various species discussed, or to consider too fully their agricultural and commercial aspects. Such information can be obtained from supplementary readings which should be an integral part of the work of the course. A list of 160 important reference works is appended, and the instructor will find numerous articles available in current magazines, government bulletins, and similar sources. For the benefit of anyone interested in the taxonomic phases of the subject, a systematic list of the species discussed is appended. Although intended primarily as a textbook, this work should have an appeal to the ordinary reader, since material of too technical a 'nature has been avoided as far as possible. The author wishes at this time-to express his sincere apprecia­ tion of all the assistance that has been granted him during the preparation of the book. He desires especially to thank Professor Oakes Ames, who has read the entire manuscript, for his constant interest and valuable suggestions; Professor Samuel J. Record, F. Tracy Hubbard, and Horace N. Lee, who have criticized various sections; and all others who have in any way contributed with advice and comments. Special thanks are due the staff of the Botanical Museum of Harvard University for their cour­ tesy in placing the facilities of the museum at his disposal and for their friendly cooperation'in many ways. PREFACE Vll The author is also deeply indebted to many institutions and individuals who have contributed photograph~ for use as illustra­ tions. In this 'connection his thanks are due the Bureau of Plant Industry and the Forest 'Service of the United States Department of Agriculture; the Botanical Museum, the Arnold Arboretum, and the Gray Herbariu~ of Harvard University; the Massachusetts State College; the University of Maine; the University of Minnesota; the Connecticut Agricultural Experiment Station at New Haven; Breck and Company; the United Fruit Company; E. L. Patch and Company; the United States Beet Sugar Association; the Minute Tapioca Company; and the following individuals: Professor S. J. Record, Professor H. W. Youngken, Professor W. H. Weston, Professor D. H. Linder, Dr. F. M. Dearborn, and Mr. R. E. Schultes. The author further wishes to express his indebtedness to Ginn and Company, the McGraw-~ill Book Company, Inc., P. Blakiston's Son & Company, The Macmillan Company, World Book Company, and the editors of the American Journal of Pharmacy for permission to reproduce various figures which have appeared in their publications, due credit for which is given in each instance. ALBERT F. HILL. HARV ARD UNIVERSITY, April, 1937. CONTENTS PAGE PRE~'ACE ...•.• V INTRODUCTION CHAPTER I THE IMPORTAN;t:E AND NATURE OF PLANT PRODUCTS. 1 • "INDUSTRIAL PLANTS AND PLANT PRODUCTS CHAPTER II FIBERS AND FIBER PLANTS. 21 CHAPTER III FOREI-lT PRODUCTS: WOOD AND CORK . 62 CHAPTER IV FORERT RESOURCES. , 96 CHAPTER V TANNING AND DYE MATERIALS .. .. 134 CHAPTER VI RUBBER AND OTHER LATEX PRODUCT:';. 153 CHAPTER VII f GUMS AND RESINS . 168 CHAPTER VIII ( ESSENTIAL OILS . .: ... 194 CHAPTER IX FATTY OILS AND WAXES .. ....... 210 CHAPTER X SUGARS, STARCHES, AND CELLULOSE PRODUCT". 228 DRUG PLANTS AND DRUGS CHAPTER Xl MEDICINAL PLANTS. 251) ix x CONTENTS· PAGE CHAPTER XII FUMITORIES AND MASTICATORIES . 279 FOOD PLANTS CHAPTER XIII • THE HISTORY AND NATURE OF FOOD PLANTS .. 297 CHAPTER XIV THE MAJOR CEREALS. 309 CHAPTER XV THE MINOR CEREALS AND SMALL GRAINS . • .1 . 334 CHAPTER XVI LEGUMES AND NUTS .. ' · . 352· CHAPTER XVII VEGETABLES . o' • • • • 377 CHAPTER XVIII FRUITS OF TEMPERATE REGIONS . : 406 CHAPTER XIX TROPICAL FRUITS. 429 FOOD ADJUNCTS CHAPTER XX SPICES AND OTHER FLAVORING MATERIALS. · \. 460 \ . CHAPTER XXI BEVERAGE PLANTS AND BEVERAGES. · . 497 '(' APPENDIX SYSTEMATIC LIST OF SPECIlllS DISCUSSED. 527 BIBLIOGRAPHY . 553 INDEX ..... 561 ECONOMIC BOTANY CHAPTER I THE IMPORTANCE AND NATURE OF PLANT PRODUCTS THE IMPORTANCE OF PLANTS AND PLANT PRODUCTS TO MANKIND The average man is likely to consider himself as a being apart from the rest of the organic world, enabled by reason of hi:-; supe­ rior intellect to lead a self-sufficient and independent exi~tence. He loses sight of the fact, or is ignorant of it, that he is absolutely dependent on other organisms for his very life, and his material happiness as well. His superior intelligence has made him more dependent rather than less so. Although various animal and mineral products contribute to his welfare, it is the plant kingdom that is most essential to man's well-being.