DRY-FARMING

A SYSTEM OF AGRICULTURE
FOR
COUNTRIES UNDER LOW RAINFALL




BY
JOHN A. WIDTSOE, A.M., Ph. D

PRESIDENT OF THE AGRICULTURAL COLLEGE OF UTAH


Jethro Tull
Born 1674; died 1741. His methods of soil tillage lie at the foundation of the modernsystem of dry-farming.

NEW YORK
THE MACMILLAN COMPANY

1920

All rights reserved




T0
LEAH
THIS BOOK IS INSCRIBED
JUNE 1, 1910






PREFACE

Nearly six tenths of the earth's land surfacereceive an annual rainfall of less than twenty inches, and can be reclaimed for agriculturalpurposes only by irrigation and dry-farming. A perfected world-system of irrigationwill convert about one tenth of this vast area into an incomparably fruitful garden,leaving about one half of the earth's land surface to be reclaimed, if at all, bythe methods of dry-farming. The noble system of modern agriculture has been constructedalmost wholly in countries of abundant rainfall, and its applications are those demandedfor the agricultural development of humid regions. Until recently irrigation wasgiven scant attention, and dry-farming, with its world problem of conquering onehalf of the earth, was not considered. These facts furnish the apology for the writingof this book.

One volume, only, in this world of many books,and that less than a year old, is devoted to the exposition of the accepted dry-farmpractices of to-day.

The book now offered is the first attempt toassemble and organize the known facts of science in their relation to the productionof plants, without irrigation, in regions of limited rainfall. The needs of the actualfarmer, who must understand the principles before his practices can be wholly satisfactory,have been kept in view primarily; but it is hoped that the enlarging group of dry-farminvestigators will also be helped by this presentation of the principles of dry-farming.The subject is now growing so rapidly that there will soon be room for two classesof treatment: one for the farmer, and one for the technical student.

This book has been written far from large libraries,and the material has been drawn from the available sources. Specific references arenot given in the text, but the names of investigators or institutions are found withnearly all statements of fact. The files of the Experiment Station Record and DerJahresbericht der Agrikultur Chemie have taken the place of the more desirable originalpublications. Free use has been made of the publications of the experiment stationsand the United States Department of Agriculture. Inspiration and suggestions havebeen sought and found constantly in the works of the princes of American soil investigation,Hilgard of California and King of Wisconsin. I am under deep obligation, for assistancerendered, to numerous friends in all parts of the country, especially to ProfessorL. A. Merrill, with whom I have collaborated for many years in the study of the possibilitiesof dry-farming in Western America.

The possibilities of dry-farming are stupendous.In the strength of youth we may have felt envious of the great ones of old; of Columbuslooking upon the shadow of the greatest continent; of Balboa shouting greetings tothe resting Pacific; of Father Escalante, pondering upon the mystery of the world,alone, near the shores of America's Dead Sea. We need harbor no such envyings, forin the conquest of the nonirrigated and nonirrigable desert are offered as fine opportunitiesas the world has known to the makers and shakers of empires. We stand before an undiscoveredland; through the restless, ascending currents of heated desert air the vision comesand goes. With striving eyes the desert is seen covered with blossoming fields, withchurches and homes and schools, and, in the distance, with the vision is heard thelaughter of happy children.

The desert will be conquered.

JOHN A. WIDTSOE.

June 1, 1910.