FOODS AND FOOD PRODUCTION

ENCYCLOPEDIA

FOODS AND FOOD PRODUCTION

ENCYCLOPEDIA DOUGLAS M CONSIDINE, P.E.

Editor-in-Chief (Fellow, American Association for the Advancement of Science;

Instrument Society of America; Senior Member, American Institute of Chemical Engineers)

GLENN D. CONSIDINE Managing Editor

(Member, American Society for Metals; Institute of Food Technologists)

Inm5I VAN NOSTRAND REINHOLD COMPANY ~ NEW YORK CINCINNATI TORONTO LONDON MELBOURNE

ISBN-13 :978-1-4684-8513-4 e-ISBN-13 :978-1-4684-8511-0 DOl: 10.1007/978-1-4684-8511-0

Copyright © 1982 by Van Nostrand Reinhold Company Inc. Softcover reprint of the hardcover 1 st edition 1982 Library of Congress Catalog Card Number: 81-19728

All rights reserved. No part of this work covered by the copyright hereon may be reproduced or used in any form or by any means-graphic, electronic, or mechanical, including photocopying, recording, taping, or information storage and retrieval systems-without permission of the publisher.

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Library of Congress Cataloging in Publication Data Main entry under title:

Foods and food production encyclopedia.

1. Food-Dictionaries. 2. Agriculture­Dictionaries. 3. Food industry and trade­Dictionaries. I. Considine, Douglas Maxwell. TX349.F58 664'.03'21 81-19728 AACR2

A Glance at This Encyclopedia

To combine scope of topical coverage with reasonable depth of detail of a field that is as broad and com­plex as foods and their production, and to meet these objectives with one volume, requires a large book. Tight editing alone will not accomplish this objective simply because there is so much to be described. Statistically, this books contains:

2322 printed pages 1.9 million words

1201 separate editorial entries 2950 cross-reference headings 1006 illustrations 587 tables

7500 items in alphabetical index

Three Fundamental Stages of Food Production

In this encyclopedia, three fundamental stages of food production are addressed: 1. The start or initiation of the natural food-growth cycle-the seeds, rootstocks, seedling trees, the

mating or artificial insemination of livestock, the stocking of fisheries, among others. 2. The nurture of growing plants and animals through harvest, roundup, and postharvest preparation,

from which point "raw" food materials go either to (a) the fresh market; or (b) processors. 3. The processing of "raw" food materials into more refined and complex products for the marketplace.

Traditionally, in some countries, the processing aspects of food production have been referred to as food technology.

Interdisciplinary Approach. By recognizing the aforementioned three fundamental stages of food production, the editors of this volume immediately forced the application of an interdisciplinary approach to its content. Most permanent reference books on food and food production in the world's libraries, as well as journals in the food field, tend to concentrate on only one of the three fundamental stages. Thus, there are numerous volumes that embrace botany, horticulture, plant and animal genetics, agronomy, animal husbandry, fisheries, and food (processing) technology as a few examples. There are even greater numbers of volumes that cover highly vertical aspects of these fields. This traditional approach to the food field, while certainly useful and justified on many grounds, does tend to reinforce the continuation of a limited disciplinarian approach. During the past few decades, many authorities in the food field have stressed the need for a greater interchange among the numerous food field disciplines and it is hoped that, in its own small way, this encyclopedia will make a contribution in this regard.

Stress on Fundamentals. An interdisciplinary approach to food topics is not undertaken without the responsibility for furnishing background supportive information so that the user of the encyclopedia, if not fully versed, will have reasonable explanations and definitions at hand within the one volume without having to turn to a number of additional reference books. Thus, considerable stress is given throughout this encyclopedia on fundamentals of botany, biochemistry, genetics, processing sciences, and nutrition, among other fields.

International Inputs. Although it is not feasible to describe the detailed differences in food production from one country to the next, where one or a few countries are principal producers of a given crop, or where particularly interesting and technically helpful practices approach the unique in any given country or region, these are included. In other words, from a crop standpoint and from a technology standpoint, the descriptions in this volume are by no means confined to just a few of the most highly advanced coun­tries, but embrace less advanced as well as sophisticated methodologies. Organizationally, however, this volume does not provide a country-by-country assessment of food-producing methods. It should be men­tioned, however, that, in terms of all principal crops and products described, statistics of production are

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vi A GLANCE AT THIS ENCYCLOPEDIA

given for all countries that produce over 1 % of a given crop or product. Throughout this volume, metric and English equivalents are used wherever quantitative data are given­

dimensions, temperatures, pressures, yields, etc. There are, of course, thousands of such instances in the book. Further, at the end of the volume (Appendix 3) are included 20 tables of useful conversion informa­tion covering weight, area, liquid volume, and bulk volume.

Emphasis on Quantitative Information and Precision. The inclusion of nearly 600 tables in this volume is testimony to the fact that wherever reliable information is available and within the overall scope of the book, it is used to augment, or in lieu of qualitative descriptions. This applies not only to statistical sum­maries, but also to descriptions of physical objects, processes, and procedures. Similarly, precision is stressed in the use of Latin and scientific terms, along with common English names, for species, subspecies, diseases, and microorganisms-wherever such usage will remove any doubt as to what is meant. Some plant diseases, for example, may be known by different names in different regions. In such cases, synonyms are given along with the precise scientific name.

Much stress is also given to nomenclature through the use of definitions and classifying schemes. Where crops are called by different names in different parts of the world, equivalents are given. Thus, maize = com; groundnut=peanut, etc.

Bridge to More Detailed Information. This volume is designed for the specialist and generalist, and can be a "workhorse" in the library of any person who has either a constant or periodic interest in the food field. This multiple-audience approach is the result of customized editing of all material, following the well­established rule of proceeding from the general to the specific. The material in each entry or in each section of a given entry commences with answers to the most likely fundamental questions, followed by an ap­proach in-depth that will serve the needs of most readers-with exception, of course, of those specialists on a given topic. But, since no one can specialize in all aspects of the food field, particularly in view of its highly interdisciplinary character, there are many more nonspecialists than specialists.

For those users of the book who want to probe a topic much deeper, generous reference lists are in­cluded at the ends of nearly all entries, with the exception of short definitions. These references are up-to­date as of the early 1980s, but because references going back 10 or 20 years may still be quite pertinent, these are also included. In some instances, classic references that go back a century or more are included for those readers who desire a historical perspective on a given topic. Thus, the volume, in addition to serving as a basic state-of-the-art reference, also can serve as a useful bridge to further information.

Working lliustrations. Figures, whether photographs or diagrams or maps, are used only when they convey a lot of information and not simply for esthetic purposes. Admittedly, because so many raw food substances and prepared food products possess a remarkable beauty of their own, the editors have had to work hard to avoid the temptation of using pictures because they are pretty. Where diagrams, graphs, etc., are included, they are reproduced in sufficient size so that they can be interpreted with a working degree of accuracy.

Research. Where active research projects are underway, and these are many, an effort is made to in­clude brief descriptions of these activities, always accompanied by references to recent papers, reports, etc., that are pertinent. This bridges current information to the future.

Cross-references. The alphabeticized encyclopedia format is undeniably a very convenient format to use. But, without very generous use of cross-references, some of the convenience of the encyclopedia can be lost. For this reason, many hundreds of cross-references appear within the texts of the entries; further a large number of references are inserted alphabetically throughout the book, these serving as a coarse index to the entire book. At the end of the volume will be found an alphabeticized listing of cross-references (several thousand).

Topical Content of Volume (Abridged)

Food Commodities. All major and a number of minor commodities are described in separate alphabeti-cal entries in this volume and include:

Fruits and melons: 60 kinds, from akee to watermelon. Vegetables and pulses: 63 kinds, from artichoke to yam. Nuts: 15 kinds, from almond to walnut. Oil and seed crops: 11 entries, ranging from cottonseed to sunflower. Field crops and grains: 21 entries, ranging from alfalfa to wheat. Special kinds of crops, difficult to classify, such as mushrooms. Livestock and poultry: 11 entries, ranging from beef and dairy cattle, through deer and large game,

goats, poultry, rabbit and small game, sheep, and swine, as well as comprehensive coverage of feedstuffs and silage and silage fermentation.

Seafoods and freshwater f"Jshes: Over 30 entries on various species of fishes and seafoods, including aquaculture, crustaceans, mollusks, and turtles.

A GLANCE AT THIS ENCYCLOPEDIA vii

Wherever possible, the food commodity entries are self-contained, but replete with cross-references to associated information to be found elsewhere in the volume. A typical entry will commence with a terse review of scientific classification, terminology, and nomenclature which serves to structure the remainder of the entry. Interesting historical descriptions are kept brief unless they contribute heavily to an under­standing of the present state of the art. Worldwide production statistics are included, usually with sup­porting descriptions of the leading producers. For major commodities, trade (import/export) data are included. Production in the United States is delineated by states or regions. Varieties in the case of plants, breeds in the case of cattle, etc., are described in terms of their relative advantages and limitations. Tradi­tional and advanced cultural and husbandry methodologies are described. In the case of crops, coverage includes preparation for planting, fertilizing, application of chemical controls, planting, cultivating, ir­rigating; harvesting-by hand, mechanized, semiautomated, whichever stage of development has been reached; postharvesting procedures, such as cooling and packing (for fresh market produce), then pro­cessing if commodities are to be preserved in some fashion. In the case of fruits, orchard planning, culture­planting, rootstock selection, pruning, training, thinning, followed by packing and processing descriptions. In the case of livestock and poultry, selection and breeding of stock, management of pasture and rangeland, construction and operation of housings (particularly for poultry), feeding, environmental controls, protec­tion from pests and diseases are covered. Meat properties and processing, with much emphasis upon re­search into musculature and textural properties, are described in a separate entry. Milk and dairy products are also covered in a separate entry, a very comprehensive entry which includes all major and a number of minor products produced from milk and whey. Some 50 separate kinds of cheese are described in individual supportive entries.

Processes and Processed Foods. Where a given process appears time and time again in connection with numerous commodities, considerable duplication can be avoided by including such operations and processes in separate entries, making observations of specialized techniques for any given commodity in the com­modity entry. Operations treated in this fashion include: Blanching, centrifuging, drying and dehydrating, evaporating, fermenting, filtering, food irradiation, freeze-concentrating, freeze-drying, freeze-preserving, homogenizing, reverse osmosis, solvent extraction, spray drying, thermal (heat) preserving, and ultrafiltra­tion. Processes that tend to be unique to a given product, such as ice cream, cheese, etc., are fully described in the entry on the product. Because intermediate-moisture foods apply to so many commodities, there is a separate entry on this topic, although intermediate-moisture is covered in numerous commodity entries as well. These are held together by way of cross-references and can be found through reference to the Alphabetical Index.

There are also several processing-related topics, such as sensory evaluation, texture and rheology of foods-these covered in separate entries.

Also included on processing and processed food is a comprehensive review of beverages and beverage­related commodities-beer and other malt beverages, brandy, champagne, coffee, gin, hops, liqueurs and cordials, malt, rum, soft drinks, tea, vodka, whiskey, and wine. Numerous wines are described in separate supportive entries. Much of the entry on grape is devoted to their selection and culture for processing into wines.

There are separate entries on maize (corn) processing and maize products; and soybean processing, with emphasis upon the multiple uses of soybean.

Diseases and Pests of Plants and Animals. Because they are major restraints to food productivity, much attention is given to insects and other pests of all kinds, as well as to bacterial, fungus, and virus diseases. There are separate entries on these topics as well as coverage in connection with specific processed products. There are well over 100 separate entries on insects and pests. There are special entries on dried­fruit insects and grain-storage insects. Foodborne diseases as they affect human consumers of foods are described in considerable detail in a separate entry. These entries stress applied microbiology and controls and tie closely to the numerous entries on control chemicals.

Control Chemicals. To support the overall entries on insecticides and insecticide application, there are 107 separate entries on specific insecticides. Similarly, this is the case with herbicides (58 supporting entries on specific herbicides); and with fungicides (73 entries); and nematicides (l0 entries). Precautions in the use of control chemicals is stressed. Since this volume is of international scope, some control chemi­cals no longer permitted in some countries are included if they are still allowed in some other countries. Chemicals banned in the United States are so noted. There is also coverage of plant growth regulators and modifiers in depth, including such materials as daminozide, ethephon, gibberellic acid and gibberellin plant growth hormones.

Land and Soil-related Topics. In this rather diverse category of topics are included coverage of climate and food production; crop surveillance by satellite; fertilizers and soil conditioners; irrigation; land manage­ment; soil and soil conservation. Color maps relating to climate and soils are included in the Introductory to this volume.

Food Ingredients and Chemicals. GRAS (generally regarded as safe) substances, such as spices, season­ings, and natural flavorings, are described in approximately 40 separate entries. Food chemicals, ranging

viii A GLANCE AT THIS ENCYCLOPEDIA

from acidifiers, alkalizers, and colorants through some 40 other categories are described. Separate entries on anthocyanins, betalaines, and polymeric food additives reflect the present search for dye substitutes. The risk/benefit concept, with its relative advantages and limitations, is described. Comprehensive attention is given to many topics including flavor enhancers and potentiators and sweeteners. A very extensive table of food additives is included as Appendix I toward the back of this book.

Biochemistry and Nutrition. There are about 60 separate entries that relate to biochemistry and that tie closely with a comprehension of the nutritional functions and values of foods-as well as their effect on and employment in bringing about a number of food processes. Some of these biochemical topics include amino acids, amino acid metabolism, carbohydrates, carotenoids, choline and cholinesterase, coenyzmes, enzymes and enzyme preparations, folic acid, glycolysis, hormones, nucleic acids and nucleoproteins, pantothenic acid, phospholipids, plastids, polypeptides, proteins, protein quality and evaluation, riboflavin, ribonucleic acid, starches, thiamine, the several vitamins, and yeasts and molds. In addition to a summary of mineral importance in the diet, there are separate entries on all trace elements, treated from a biological and meta­bolic standpoint. These include entries on boron, cadmium, calcium, chloride, chromium, cobalt, copper, fluorine, iodine, iron, magnesium, manganese, molybdenum, nickel, phosphorus, potassium, selenium, sodium, sulfur, vanadium, and zinc. These biological and biochemical topics are treated not only in terms of human nutrition, but also from the standpoint of feeding livestock and poultry. These matters also are covered comprehensively in an entry on feedstuffs.

There is also an entry on dietary trends in the United States, the United Kingdom, and a few other countries. Additionally, all commodity entries carry tabular summaries of food composition and, in a majority of cases, a summary of their amino acid content. Stress is given to raw foods and raw preparations to provide the readers with a base for calculations should other nutrients be added.

Scientific Fundamentals. There are numerous entries that provide background on botanical, zoological, ichthyological, and genetic matters that are supportive to other topics as a means toward bridging the gap between numerous scientific disciplines.

Acknowledgments

Specialists in many disciplines of the food field have contributed in many ways to the preparation of this comprehensive work. Ranging from the preparation of manuscripts on complex topics, the submittal of new data for the first time, advice and counsel to the Editorial Board, the seeking out of obscure and dis­crete information, the reporting of research findings-for these activities, among others, the editors are indeed grateful. Inputs represent those of scientists, engineers, technologists, growers, processors, econo­mists, and executives and administrators who have some stake in the food field. In addition to numerous academic institutions and private industries, the editors are much indebted to numerous governmental departments, agencies, and field organizations for their cooperation, not only in the United States and Canada, but in Europe, Asia, Africa, South America, and Oceania. In particular, experts with the Food and Agriculture Organization of the United Nations in Rome, and with the United States Department of Agriculture in Washington and its numerous research and field operations located throughout the country must be mentioned as major cooperators. The editors are grateful to the governments and persons of a number of countries for the opportunity to visit field operations, to see research projects underway, and thus compare the methodologies of food production from one region to the next.

Following are some of the institutions, organizations, and firms whose people helped make the Foods and Food Production Encyclopedia a reality. Additional acknowledgments will be found throughout text.

Ag-Chem Equipment Co. (Minneapolis); Agriculture Canada; Agricultural Research Institute (Iceland); Agricultural University (The Netherlands); Ajinomoto Co. (Japan); Alfa-Laval Group (Denmark); Allis­Chalmers (Milwaukee); Ambrosia Chocolate Co. (Milwaukee); American and Delaine Merino Record Asso­ciation (Nova, Ohio); American Angus Association (Saint Joseph, Missouri); American Corriedale Associa­tion (Seneca, Illinois); American Dehydrators Association (Mission, Kansas); American Hampshire Sheep Association (Columbia, Missouri); American Hereford Association (Kansas City); American Maize-Products Co. (Hammond, Indiana); American Meat Institute Foundation (Arlington, Virginia); American Ram­bouillet Sheep Breeders Association (San Angelo, Texas); American Romney Breeders Association (Cor­vallis, Oregon); American Shorthorn Association (Omaha); American Soybean Association; Archer Daniels Midland Company (Decatur, Illinois); Ashland Chemical Company (Fords, N.J.); Aspen Institute for Humanistic Studies (Boulder, Colorado); Auckland Institute and Museum (New Zealand); Bhabba Atomic Research Centre (India); Bishop Museum (Honolulu); Boone Valley Co-Op Processing Association (Eagle Grove, Iowa); Borden Inc. (Columbus, Ohio); Brangus International (San Antonio, Texas); Brown Swiss Cattle Breeders' Association (Beloit, Wisconsin); California Almond Growers Exchange (Sacramento); California Dry Bean Advisory Board (Dinuba, California); Canning Research Institute (Bulgaria); Central Food Technological Research Institute (India); Centro Agronomico Tropical de Investigacion y Ensenanza (Costa Rica); Centro de Investigacion y Dessarrollo en Criotechnologia de Alimentos (Argentina); Centrol de Pesquisas e Desenvolvimento (Brazil); Chemetron Corp. (Louisville, Ky.); Cherry-Burrell Corp. (Cedar Rapids, Iowa); Chevron Chemical Co. (San Francisco); Chore-Time Equipment, Inc. (Milford, Illinois); Colorado State University; Columbia Sheep Breeders Association of America (Upper Sandusky, Ohio); Columbia University; Corn Refiners Association (Washington, D.C.); Custom Food Products, Inc. (Chicago); DEC International, Inc. (Fond Du Lac, Wisconsin); Deere and Co. (Moline, Illinois); Defence Food Re­search Laboratory (India); Diamond Automation Division (Farmington, Michigan); Diamond Shamrock Chemical Co. (Morristown, N.J.); Diamond/Sunsweet Inc. (Stockton, California); Dole Corp. (Hawaii); Dorr-Oliver (Stamford, Conn.); Dow Chemical Co. (Midland, Michigan); Dupps Co. (Germantown, Ohio); Dynapol (Palo Alto, California); Eastman Chemical Products Inc. (Kingsport, Tennessee); Eindhoven University of Technology (The Netherlands); EI Mollino Mills (City of Industry, California); Farmhand (Hopkins, Minnesota); Florida State Horticultural Society; FMC Corporation (Chicago); Foremost Foods Co. (San Francisco); Garst and Thomas Hybrid Corn Co. (Coon Rapids, Iowa); General Mills Chemicals,

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x ACKNOWLEDGMENTS

Inc. (Minneapolis); Gold Kist, Inc. (Atlanta); Hawk Bilt (Vinton, Iowa); Hebrew University (Jerusalem); Hoffman-La Roche Inc. (Nutley, N.J.); Icelandic Fisheries Laboratories (Iceland); ICP Cocoa Inc. (Camden, N.J.); Illinois Institute of Technology; Imperial College of Science and Technology (London); Indiana University; Institute for Technology and Storage (Israel); Institute of Nutrition of Central American and Panama (Guatemala); Instituto de Investigaciones Technologicas (Colombia); Instituto de Technologica de Alimentos (Brazil); Instituto di Fisica Technica (Italy); Instituto Technologico de Chile; Instituto Venezolano de Investigaciones Technologicas y Industriales (Venezuela); Instron Corp. (Canton, Massa­chusetts); International Apple Institute; International Association of Milk, Food, and Environmental Sanitarians; International Harvester Co. (Chicago); International Multifoods (Minneapolis); Iowa State University; Irvin and Johnson Ltd. (South Africa); Israel Institute of Technology; J & L/Honiron En­gineering Co. (Jeanerette, Louisiana); Kikkoman Shoyu Co., Ltd. (Japan); Koopmans Engineering B. V. (The Netherlands); Kyoto University (Japan); Lilliston Corp. (Albany, Georgia); Marine Resources Research Institute (Charleston, South Carolina); Massey University (New Zealand); Mauna Loa Macadamia Nut Corp. (Hawaii); McCormick Industrial Flavor Div. (Hunt Valley, Maryland); A. G. McKee and Co. (Chicago); Meat Research Laboratory (Australia); Michigan State University; Miles Laboratories, Inc. (Elkhart, Indi­ana); Nagano State Laboratory of Food Technology (Japan); Natick Research and Development Command (U.S. Army); National Association of Animal Breeders (Columbia, Missouri); National Food Research In­stitute (Japan); National Institute of Health (Japan); National Peach Council; National Peanut Council; National Renderers Association; Nestle Products Technical Assistance Co., Ltd. (Switzerland); North Carolina State University; Northern Nut Growers Association; Ocean Spray Cranberries, Inc. (Hanson, Massachusetts); Ohio State University; Oregon Filbert Commission; C. J. Patterson Co. (Kansas City); Peavey Industrial Foods Group (Minneapolis); Pillsbury Co. (Minneapolis); Pioneer Hi-Bred International, Inc. (Des Moines, Iowa); Poland China Record Association (Galesburg, Illinois); Potato Board; Procter and Gamble Co. (Cincinnati); Protein Grain Products International (Washington, D.C.); Purdue University; Ralston Purina Co. (Saint Louis); Raven Industries, Inc. (Sioux Falls, South Dakota); Rensselaer Polytechnic Institute; Rice Council, Rohm and Haas Co. (Philadelphia); Santa Gertrudis Breeders International (Kings­ville, Texas); Shizuoka University (Japan); Soil Conservation Society of America; Stabilisierungsfonds fiir Wein (Mainz, Germany); A. E. Staley Manufacturing Co. (Decatur, Illinois); Stork Bowen Engineering, Inc. (Somerville, N.J.); Struthers Scientific and International Corp. (New York); Sunkist Growers, Inc. (Sher­man Oaks, California); Texas A & M University; Trago Corp. (Palo Alto, California); Tropical Products Institute (London); Union Carbide Corp. (New York); United Fresh Fruit and Vegetable Association (Alexandria, Virginia); Universal Foods Corp. (Milwaukee); Universidad de Buenos Aires; Universidad Nacional del Sur (Argentina); University of California; University of Denver; University of Georgia College of Agriculture; University of Helsinki; University of Ibadan (Nigeria); University of Idaho; University of Illinois; University of Kentucky; University of Maine; University of Malaya (Kuala Lumpur); University of Minnesota; University of Novi Sad (Yugoslavia); University of Sri Lanka; University of Surrey (Britain); University of Tennessee; University of Tokyo; University of Utrecht (The Netherlands); University of Washington; University of Wisconsin; Washington and Idaho Dry Pea and Lentil Commission; Whiting Corp. (Harvey, Illinois); Woods Hole Oceanographic Institution (Woods Hole, Massachusetts); among others.

An Introductory FOOD-PRODUCING SYSTEMS

Their Nature and Fundamental Natural Restraints

In many parts of the world, food production has undergone a methodical and technological revolution, particularly since the introduction of extensive mechanization and the beginnings of automation, which commenced on a modest scale prior to World War I, and continued with the interfacing of chemical and biological technology which accelerated greatly after World War II. The late 1970s and early 1980s have witnessed the review of past problems and solutions and the creation of new problems, many of them waiting for solutions. Although advancements continue at a good pace, the many tens of thousands of persons who bear some responsibility for food production are putting past achievements into focus and against a backdrop of current and future needs, considering not only the fundamental need to feed the world's population, but, at the same time, assuring human health, protecting the environment, and conser­ving energy-all areas against which food production activities impact heavily. The skills of food-production technology, so dramatically utilized over the past half-century, are being called upon to exert an effort and influence of much greater magnitude during the remainder of the present century.

In this brief introductory, the principal classes of food-producing systems are described, along with mapped depictions of those natural restraints within which any food-production system must operate, notably climate and soils.

Classification of Food-producing Systems

Considering the score or more of important variables that affect food production operations, it is not surprising that a really satisfactory classification of a systems nature remains to be constructed. Although there are many similarities, dairy farming is one kind of system, ranching is another kind of system, and subsistence farming in a developing country represents still another system. The total system reflects the influence of prevailing climate, the kinds of crops or other products grown, the regional economical and ecological factors, the degree of mechanization used, the intensity of fertilization and use of control chemi­cals, the water supply, among many other factors. How, then, can logical groupings of these variables be made in an effort to separate food production into a relatively few categories that can easily be grasped by the mind, even though in one case climate and topography may be overriding considerations, while local economy and skills status may be paramount influences in another case?

As pointed out in more detail in the entry on Crop Surveillance by Satellite, the pioneers of interpreting land imagery into useful inventorying and planning information were faced with the need for just such a systems classification. Even though quite imperfect, containing some inconsistencies and redundancies, the classification of Table 1 has proved quite helpful in interpreting and presenting surveillance data. See also Map. No.1. Further, this classification, which hopefully can be much improved over the years ahead, can also be helpful to persons who not only have interest in specific crops, specific production data, specific irrigation data, but also have an interest in an overview that facilitates analysis of a complex subject. A less complex, more qualitative classification of agricultural systems is given by Loomis (Sci. Amer., 235, 3, 1976).

TABLE 1. BASIC SYSTEMS OF FOOD PRODUCTION (A multifaceted classification)

NOMADIC HERDING

One of the most ancient of agricultural systems. Animals, grazed on native vegetation, are the primary products. Nomadic peoples cultivate very few crops.

Locations: Herding in cold climates is found along the north and west coasts of Alaska, parts of northwestern Canada, the northern coasts of Scandinavia, including Lapland, and northwestern Russia. Herding in hot climates occurs mainly in the Sahara area of Africa, parts of southern Africa, the Arabian Peninsula, the Negev and Sinai Desert regions, parts of south­western Asia, including Pakistan and India, as well as in the west-central portions of China and Mongolia.

Climate: Arid conditions-either very hot or very cold. Hot, arid desert and middle-latitude climates of Africa and Asia are not predisposed to production of vegetative growth. Precipitation is minimal. The northern areas may receive from 10 to 20 inches (25.4 to 50.8 centimeters) of rainfall annually. The southern areas receive under 12 inches (30.5 centimeters) annually. Desert areas may receive less than 4 inches (10.2 centimeters) of rainfall per year. In the northern regions, the frost-free growing season is only from 60 to 90 days.

Topography: Plateaus are the most prevalent landform within these regions. The plains in northern Russia and India, and the mountains in southern China and western Asia provide natural pastures for nomadic herds.

Mechanization: Nomadic herding is an extensive grazing operation similar in many respects to livestock ranching. To provide a sufficient food supply for grazing, large expanses of land are required. The soils in these areas are not tilled.

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xii AN INTRODUCTORY

TABLE 1. BASIC SYSTEMS OF FOOD PRODUCTION (A multifaceted classification) (cont.)

Nomadic herding is primitive and is probably the most meager of agricultural operations. The vast expanses of land, harsh climatic conditions, and economic position of various nomadic tribes have precluded the use of modern agricultural ma­chinery. Nomadic herding has been declining for several decades as the result of increasing numbers of tribes turning to sedentary agriculture, particularly on the fringe areas of their previous workings where better water supplies and soils are aVailable. Camels and caravans are progressively being replaced by trucks and other vehicles. As agricultural operations become more consolidated, increased usage of machinery will occur-and nomadic herding as a system of food production will become even more limited.

Soils: In the northern regions, soils are mainly inceptisols, spodosols, and mountain soils. In the southern regions, the soils are aridisols, entisols, mollisols, and some mountain soils. See Table I in entry on Soil.

RUDIMENTARY SEDENTARY AGRICULTURE

This system of agriculture is rather primitive and is a nonmigratory practice associated with tropical and subtropical areas. Subsistence crops include maize (corn), potatoes, cacao, wheat, barley, millet, sorghum, sweet potatoes, cassava, ground­nuts (peanuts), and bananas.

Locations: This system of agriculture is found in parts of Central America, the east coast of Brazil, and the Andes Moun­tains area of South America. Small areas of rudimentary sedentary agriculture are also found throughout central Africa and southeastern Asia, including Burma and Indonesia.

Climate: This system is often practiced in the higner elevations of the less developed countries. With increases in elevation, rather dramatic climatic changes can be encountered within a relatively small area. This type of changeable climate is commonly called highland climate or high-altitude climate. Precipitation is quite variable. Parts of the Andes Mountains and western Ethiopia may receive as little as 8 inches (20.3 centimeters) ofrainfall annually, while in Indonesia and Burma, the rainfall may range from 80 to 200 inches (202 to 508 centimeters) per year. The frost-free growing season is year­long, unless modified by altitude. Topography: Most of the regions exhibit mountainous terrain. However, the plains of Yucatan Peninsula of Mexico are cultivated in this manner.

Mechanization: The majority of people in these areas is engaged in growing essentially just enough food to sustain life. Practically no fertilizers or new seed varieties are used. Thus, there is a very low crop yield per unit of land worked. Lack of skills, low economic levels, small size of plots, and mountainous topography preclude intensive introduction of modern agricultural technology, including machines. Soils: Primarily mountain soils with some alfisols, inceptisols, and ultisols present. See Table I in entry on Soil.

SUBSISTENCE AGRICULTURE This agricultural system is typical of practice in several Asian areas. A variety of food crops includes wheat, barley, maize (corn), rice, potatoes, millet, sorghum, groundnuts (peanuts), sugar cane, soybeans, and bananas. The ability of many of these densely populated regions to feed large masses of people is highly dependent upon the long growing season which permits more than 1 crop per year to be planted and harvested. Crop rotation is widespread. Large river systems in several of these areas permit extensive irrigation. With certain exceptions, varying from 1 country to the next, the crops produced are consumed by the people of the regions where grown. However, even with this land-intensive and labor-intensive system, many countries still must import large quantities of foodstuffs.

Oimate: Unlike most agricultural systems, climate is not a primary factor in delineating this type of system. Over years of experience, growers have learned which crops are likely to yield reasonably well for a particular region. Climates include the tropical monsoons of India, Pakistan, and southeastern Asia, as well as the humid middle-latitude climate of northern China. Subsistence agriculture is also found in arid, semiarid, and mountainous climates. There is a large range in amount of rainfall received from one area to the next. The growing season is year-long in many of these areas, but becomes shorter in areas of higher elevation and latitude.

Mechanization: Intensive land tillage is associated with subsistence agriCUlture. Fields are usually small (under 10 acres; 4 hectares), with the exception of Chinese communal farms. Irrigation (tom major river systems is a common practice. Simple machinery is used in those countries which slowly are changing from a developing economy to a more developed, self-supporting economy. However, unless shared, costly machinery is not usually economically feasible.

RICE-DOMINANT SUBSISTENCE AGRICULTURE

This is a specialized form of subsistence agriculture. Most of the produce is consumed by the local populace. Rice is so dominant that it overshadows other crops in the system. However, lesser crops include tea, sorghum, sugar cane, manioc, groundnuts (peanuts), coffee, and some fiber crops. It is not uncommon to fmd farms under 4 acres (2 hectares) in size. Most regions produce two to three crops on the same land per year because of the long growing season and the availability of irrigation water.

Climate and Locations: Three major climate classes are characteristic of rice-growing regions: (1) Wet and dry tropical climate of India, Vietnam, Bangladesh, Cambodia, and Thailand, which has a well-defmed dry season accompanied by one or two rainy seasons; (2) rainy tropical climate of Burma, Nepal, Malaysia, Indonesia, and the Philippines where there is rainfall throughout the year and where temperatures are continuously warm to hot; and (3) humid subtropical climate of China, Japan, and Taiwan, characterized by long warm summers, cool winters, and rainfall throughout the year.

Topography: Rice-growing regions are noted for: (1) Broad, flat river flood plains (lowland rice); and (2) terraced slopes (upland rice). Frequently, because rice is so important as a local source of food, very steep hillsides, requiring laborious irrigation methods, will be intricately terraced. In many regions, hand labor is the main source of power. Slowly, mecha-

ANINTRODUCTORY xill

TABLE 1. BASIC SYSTEMS OF FOOD PRODUCTION (A multifaceted classification) (cont.)

nization is spreading into China, Japan, and India and, in a few select areas, exceptional mechanization, such as rice­planting machines, have been introduced (notably in Japan). The very small size of rice-producing tracts in many countries has essentially precluded adoption of extensive mechanization.

PLANTATION AGRICULTURE

This system of agriculture involves large, centrally managed estates in the tropical and subtropical regions-and was once prevalent in the southeastern United States. Some plantations are essentially devoted to one crop. Major producing areas vary considerably and are scattered throughout Central America, the Caribbean, the east coast of South America, central and southern Africa, Hawaii, southern Asia, Malaysia, Indonesia, and the east coast of Australia. Plantation crops include coffee, cacao, coconut, bananas, pineapple, sugarcane, tea, manioc, and several fiber crops. Within the last several decades, plantations have become profitable subsidiaries of large corporations (usually headquartered in major importing countries). Heavy emphasis is placed upon exporting plantation crops to large consuming regions that may be located considerable distances from the plantations.

Climate: The wet and dry tropical climate is most prevalent where large plantations are located, although some areas (for certain crops) experience a rainy tropical climate. Average annual precipitation is moderate to heavy, at least 40 inches (102 centimeters) per year. The growing season is year-long. There are several exceptions to these generalities.

Topography and Soils: Because of crop specialization on plantations, it is meaningless to generalize as regards topography and soils. Trees or shrub crops can be grown on hillside plantations, while pineapple and sugarcane require level fields.

Mechanization: Very intensive land tillage is practiced. Stringent scientific management programs and improved crop varieties generally characterized the well-managed, profitable plantation. Large-scale plantation organizations lend them­selves to a high level of mechanization, even though labor may be relatively inexpensive. Machines are used to plough the land and plant the crops, but human labor is still required to harvest many of the crops.

SHIFTING CULTIVATION

Today, this is an agricultural system associated mainly with the humid tropical regions, including the Amazon River basin of Brazil and portions of Bolivia, Peru, Colombia, Venezuela, and Central America. It is also widely apparent in central Africa. Shifting cultivation typically involves cutting and burning off the native vegetation, cultivating fields for a few years, and then abandoning the land for fresh clearings. There is a rotation of fields, not crops, and growers may require 5 times as much land as is cultivated in order to maintain even 75% of original soil fertility. This type of agriculture has very low productivity and is a primary cause of later water and wind erosion of soils. The Great Plains region of the United States essentially was subjected to this type of unplanned, careless form of agriculture a century or more ago and this resulted in erosion of millions of acres of soil, leading to such disasters as the Dust Bowl. See Soil Conservation.

Topography: As found today, the terrain associated with shifting cultivation in South America is primarily plains and hilly lands. In Africa, hills and plateaus are cultivated. In Asia, land forms range from plains to mountains. One of the main features of shifting cultivation, as observed from reconnaissance satellites, is a patchwork pattern of small fields located on hillsides and scattered among strips of forest.

Mechanization: This is one of the least technical of agricultural systems and is highly dependent upon crude tools with assistance from human and animal power. Dense plant growth hinders the use of modern farming equipment (even should it be considered). No fertilizers are used. Retention or reestablishment of soil fertility is left to long periods of fallow (sometimes) and replenishment by native vegetation.

TEMPERATE TO SEMITROPICAL INDUSTRIAL AGRICULTURE

This system or agriculture is distinct because of the importance of various industrial cash crops, which compete with food crops for land resources. The southern United States is a large producing region of industrial crops. Other important areas are the Nile River valley of Egypt, west central India, parts of Pakistan, and small areas in southern Russia. Cotton is the major crop. Other industrial crops (some classified broadly with foods; others identical with food crops, but used for industrial purposes) include tobacco, sunflower seeds, groundnuts (peanuts), and soybeans. Food crops, such as corn (maize), barley, rice, and wheat are frequently produced within the same regions. In some countries, industrial cash crops are raised mainly for export.

MEDITERRANEAN AGRICULTURE

This type of agricultural system is found in a zone between 30° and 45° latitude both in the Northern and Southern Hemispheres, but primarily in countries that surround the Mediterranean Sea. Other regions of the world that practice a Mediterranean agriculture include southern and west-central California, the west-central coast of Chile, the tip of South Africa, and the land adjacent to the Black and Caspian Seas in Russia and northern Iran. Major crops of this system include citrus fruits, olives and olive oil, grapes, dates, figs, subtropical fruits, tomatoes and many other vegetables. In these regions, there is a major distinction between dry land farming and irrigation agriculture. Dry land farming is common in the rougher, more mountainous areas where olives, grapes, and figs are grown on terraced slopes. The lower, more level fields and valleys are usually irrigated, producing fruits, vegetables, and cotton. Farms are usually quite small, often less than 25 acres (10 hectares) in size, except in the United States and the U.S.S.R., where crops are frequently produced on large corporate­held farms and on collective farms, respectively.

Climate: The predominant climate is commonly described as dry subtropical, with hot, dry summers and cool, moderately moist winters. The close proximity of large bodies of water has a modifying effect on climatic extremes. The average annual precipitation is between 15 and 40 inches (38 and 100 centimeters) per year. The frost-free growing season is at least 180 days, the average being 240 days or more with some areas fully frost-free.

xiv AN INTRODUCTORY

TABLE 1. BASIC SYSTEMS OF FOOD PRODUCTION (A multifaceted classification) (cont.)

Topography: Most regions of this type are typically hilly and/or mountainous, except for the cultivated plateaus of the Middle East and the Central Valley of California. Elevations range from about 610 to 2980 feet (186 to 908 meters). Mechanization: Intensive agriculture is practiced. Sometimes tree crops are interspersed with annual crops. There may be two or more harvests per year; some tree crops are harvested year.J.ong. Most of the crops are high-yielding, moisture­loving varieties, often requiring irrigation. There is a high hand.J.abor content with many of these crops. Most areas are mechanized to some degree, but harvesting technology has been slow developing. In recent years, cleverly designed har­vesting machines have come into use on such crops, but much research in this area remains to be done.

WHEAT·DOMINANT GRAIN FARMING SYSTEM Because of the great economic and nutritive importance of grain products to the world food supply, grain production is one of the most important of the agricultural systems. In the Western Hemisphere, wheat is the predominant crop in the central and north-central portions of the United States, the south-central part of Canada, and in the Pampas region of Argentina. In the Eastern Hemisphere, wheat is grown from the Black Sea to central Russia and in southern Australia.

Wheat is the dominant crop, with a major distinction between winter and spring wheat. Winter wheat is planted in the fall and harvested in early summer. Spring wheat is planted in the spring and harvested in late summer. Although winter wheat yields are usually higher, spring wheat is the type usually planted in the northern United States, Canada, and parts of the U.S.S.R. because the severe winters in some areas preclude planting winter wheat. Other major grain crops include barley, sorghum, rye, oats, and maize (com).

Climate: Wheat can be grown successfully in areas of light precipitation. The major producing areas have a semiarid, middle-latitude climate with light precipitation, warm or hot summers, cool or very cold winters. Wheat is also grown in the drier areas of the humid middle-latitude climatic regions. Precipitation generally ranges from 12 to 20 inches (30 to 52 centimeters) per year. The growing season averages from 120 to 180 days in most regions.

Topography and Soils: Wheat and cereal grasses are grown almost totally on flat or gently rolling plains. These regions encompass primarily mollisol soils with small areas of aridisols. See Table 1 in entry on Soil. Mechanization: Involving very large planting areas on relatively level country, wheat and other grains lend themselves well to mechanization. Some of the most intensive agricultural mechanization is applied in this area.

LIVESTOCK RANCHING

This form of agricultural system is found in 5 major areas of the world: (1) The western section of North America from southern Canada to central Mexico; (2) Argentina and southern Brazil and Venezuela in South America; (3) the southern part of Africa; (4) south-central Russia; and (5) much of Australia and New Zealand. Meat products and byproducts (skins, hides, wool-not a byproduct) from cattle, sheep, and goats are of major economic importance. Some of these regions are extensive natural grasslands. Other regions require much attention to retain and reestablish native vegetation. Crops are raised to support these livestock in many of these areas and may include alfalfa, maize (com), oats, sorghum, and millet. livestock ranching often borders on grain-growing regions. Rainfall in these areas may show a 50% change in total precipitation from 1 year to the next. Winter feed is purchased or grown on irrigated land. See also Beef and Dairy Cattle; Sheep.

Climate: The semiarid, middle.J.atitude or semiarid tropical climates are conducive to livestock ranching. The hot arid climates of central Russia, parts of Argentina, Africa, and Australia are most suitable for sheep or goats, although other livestock are extensively produced. The frost-free growing season is quite variable. In the low-latitude areas, the frost-free period may be essentially continuous, whereas the period becomes progressively shorter in the higher latitudes, where winter feed for livestock is an absolute necessity. Topography:Livestock can be raised on a variety of terrains provided that the prevailing climate is suitable for supporting grasses. Mechanization: Although modem machinery is used to plant and harvest feed crops for animals, the moving and rounding up of cattle still is essentially a matter of horse and manual labor . Since ranching covers extensive areas of land, helicopters have become a commonplace tool for use in ranching management in some parts of the world.

COMMERCIAL DAIRY FARMING

This type of comparatively large-scale agricultural system is found almost totally within the temperate zones in the more industrialized, developed countries. These regions include the north-central, northeastern, and the northwestern regions of the United States, as well as the south-central region of Canada and southeastern Canada. In Europe, the dairy region stretches from northern Europe through central Russia, almost to Mongolia. Dairying is practiced intensively in Switzer­land, on the east coast of Australia, and in northern New Zealand. Milk and its derivatives are the major products. Forage crops which are needed to feed livestock include pasture grasses, alfalfa, clover, com (maize) for silage, oats, and soybean meal. Commercial crops and grains are also grown and include wheat, barley, rye, potatoes, sugar beets. The size and make-up of dairy farms is quite varied and ranges from an average of about 200 acres (80 hectares) in the United States to an average of about 40 acres (16 hectares) in Denmark. Climate: Two types of climate are best suited for dairy farming: (1) the humid middle.J.atitude climate of Canada, Russia, and the northeastern United States, with its hot summers, cold winters, and year-long precipitation; and (2) the temperate marine climates of the Pacific Northwest in the United States, of Europe, Australia, and New Zealand, with moderate total precipitation, characterized by many rainy. days per year, warm summers, and cool winters. Precipitation is light-to­moderate, from 20 to 40 inches (51 to 102 centimeters) per year, but can be considerably higher. There is a great variation in the number of frost-free days, ranging from nearly frost-free in some areas to as few as 90 to 120 frost-free days in Canada and northern Europe.

ANINTRODUCTORY xv

TABLE I. BASIC SYSTEMS OF FOOD PRODUCfION (A multifaceted classification) (cont.)

Mechanization: Dairying can be considered either intensive or extensive agriculture, depending on the size of the farming operation and degree of diversification. Basically, it is an intensive operation with output per animal synonymous to maximizing output per land unit. The latest scientific methods are frequently utilized, including feed supplements, milking machines, improved forage crops, and germ-free environments. For dairying to be successful in most regions on a large scale, modem machinery is required. Dairy farmers frequently market through cooperatives.

TRUCK FARMS AND ORCHARD OPERATIONS The crops of this type of farming include numerous vegetables and fruits. Nut crops also fall within the category. Large commercial truck farms are frequently located near major marketing centers, or as in the case of citrus growers in Cali­fornia or truck farms in southern Florida, for example, they ship vegetables and fruits in winter for a thousand or more miles to market. In some truck garden areas, careful scheduling of plantings during the cooler months allows for a mini­mum of 2 different crops per year. Some of the high yields per unit ofland area are achieved in this manner. Such opera­tions also sometimes include extensive greenhouse operations.

Mechanization: Horticulture is basically a scientific farming operation with mechanization progressively replacing hand labor. There are mechanical harvesters for many of the major vegetables and fruits. In less-developed countries, the produc­tion in oasis areas tends to parallel truck operations, at least in marketing principle, but differs in use of mechanization. Packing operations have become highly mechanized. Citrus growers are often members of cooperatives.

NOTE: Adapted from data furnished by the U.S. Geological Survey, Sioux Falls, South Dakota.

Climatic Regions and Groups

The climatic regions of the earth, as shown by Map No.2, are based upon the Koppen system of classifica­tion. This system assigns geographical areas to particular climate classes in accordance with temperature and precipitation characteristics. The Koppen system is empirical. Each climate is specified in accordance with fixed values of temperature and precipitation that are compiled on the basis of yearly averages or of in­dividual months. Inasmuch as air temperature and precipitation data are among the most easily measurable surface weather conditions, it is thus relatively easy, by the Koppen system, to estimate geographical areas that are subject to one of several climate subtypes. Developed in 1918, but still used, this system is charac­terized by a letter code. The modified Koppen code used in Map No.2 is delineated in Table 2.

Much more information on climate is given in entry on Climate and Food Production. Frost-free growing seasons are depicted in Map No.3.

TABLE 2. MODIFIED KOPPEN CLIMATIC CLASSIFICATION CODES

FIRST LETTER

A

B

C

D

E

H

SECOND LETTER

S

W

f w

m

DESCRIPTION

Tropical climate. Average temperature of every month is above 18°C (64.4°F). There is no winter season. Annual rainfall is heavy and exceeds annual evaporation.

Dry climate. Potential evaporation exceeds precipitation (on the average) throughout the year. There is no water surplus. Thus, no permanent streams originate in a B climate zone.

Warm temperate climate. The coldest month has an average temperature under 18°C (64.4°F), but above _3°C (26.6°F). There is both a summer and a winter season in a C climate zone.

Snow climate. The coldest month has an average temperature under _3°C (26.6°F). The average temperature of the warmest month is above lOoC (50°F). Snow climate zones coincide approximately with the poleward limit of forest growth.

Ice climate. The average temperature of the warmest month is below 10°C (50°F). There is no true summer in an ice climate zone.

Highland climate. A climate of high altitudes, characterized by extremes of surface temperature, low atmospheric temperature, strong winds, and rarefied air.

DESCRIPTION

Semiarid climate. Features from 38 to 76 centimeters (15 to 30 inches) of rainfall annually at low latitudes. Arid climate. Most regions have less than 25 centimeters (10 inches) of rainfall annually.

Moist conditions. Adequate precipitation in all months. There is no marked dry season.

Dry season in winter (of respective hemispheres).

Dry season in summer (of respective hemispheres).

Rainforest climate, but inciliding a short dry season in monsoon type of precipitation cycle.

x~ ANINTRODUCTORY

TABLE 2. MODIFIED KOPPEN CLIMATIC CLASSIFICATION CODES (cont.)

CODE COMBINATION

Af Aw BS

BW

Cw

Cf

Cs

Df

Dw

Et

Ef

Tropical rainforest.

Tropical savanna.

Steppe climate.

Desert climate.

DISTINCT CLIMATE COMBINATIONS

Temperature, rainy climate with dry winter.

Temperate, rainy climate, most all seasons.

Temperate, rainy climate with dry summer.

Cold, snowy forest climate, moist all seasons.

Cold, snowy forest climate with dry winter.

Tundra climate.

Gimate of perpetual frost.

PreCipitation

The mean annual precipitation is depicted worldwide by Map No.4. If averaged over the total surface of the earth, the yearly rainfall is about 80 centimeters (30 inches). This rainfall is distributed quite unevenly and, among other factors, accounts for very wide variations over the earth in terms of suitability for crop production. The equatorial zone and the monsoon area of southeast Asia receive the greatest amounts of rainfall. Middle latitude regions receive moderate quantities of precipitation, whereas the desert regions of the subtropics and the areas around the poles receive very little moisture. The pattern of precipitation distribution is also complicated by local influences, such as the pattern of global winds, the distribution of land and sea, physical barriers to moisture-laden air, such as mountain ranges, and the mechanical and thermal turbulence of air over land surfaces.

Because rainfall results from the ascent and consequent cooling of moist air, the areas of heavy rainfall indicate regions of rising air. In contrast, the desert regions occur in areas where the air is warmed and dried during descent. In the subtropics, the trade winds bring ample rain to the east coasts of the continents. The west coasts tend to be drier. In high latitudes, this trend is reversed, resulting in the west coasts being generally wetter than the east coasts.

Average amounts of precipitation for a season or a year provide little indication of the regularity with which rain may be expected. This is particularly true of regions where the average amounts of rainfall are small. Past records provide some guidance, but to date meteorology has not advanced to the point where a rather precise estimate of the maximum possible precipitation for a given locality over a specified time interval can be made. Precipitation depends upon a combination of favorable factors, such as the properties of local storms as well as the interaction between storms and local topography. At best, estimates are made on the basis of theoretical calculations, utilizing statistical analyses of the most effective combinations of weather-producing factors of historical records.

In many regions, precipitation is not equally distributed in terms of time spans, in fact, the reverse situation is usually true. Some areas of the earth have very dry winters and rainy summers, whereas other areas may receive the majority of their annual precipitation in the fall and winter, following very dry summers. Although the engineering of water supplies and irrigation systems has done much to smooth out the variations in local precipitation, nevertheless the pattern of natural rainfall remains an extremely im­portant factor in determining the crop make-up of a given region as well as crop yields from one season to the next.

Soil Classification

A worldwide survey of principal soil classes is depicted by Map No. S. Definitions of soil classes noted on map will be found in Table I of entry on Soil.

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