UNIVERSITY OF CALIFORNIA agricultural ExperimentStation 
 
 College of agriculture e. j. wickson, acting director 
 
 BERKELEY, CALIFORNIA 
 
 CIRCULAR No. 9 20 
 
 ( April, 1906.) 
 
 READING COURSES IN IRRIGATION 
 
 BY 
 
 ELWOOD MEAD. 
 
 The statement made by Thaer, the noted leader in agricultural 
 science in Germany nearly a century ago, that : il An agriculture which 
 has mastered the control of water so that moisture can be supplied to 
 the soil or removed from it at will, instead of being left to chance, has 
 reached the highest possible degree of perfection," has far greater 
 significance to-day than it had when uttered ; and no more convincing 
 evidence of its truth can be found than is furnished by t{ie irrigated 
 lands of California, where the benefits of putting water on the land 
 by irrigation and the evils of not removing the surplus by drainage 
 are alike conspicuous. 
 
 The area of land irrigated is now being rapidly extended, and 
 there is every reason to believe that the rate of this extension will 
 become greater in the future. There are several million acres of land 
 susceptible of irrigation, and the water to irrigate it is now running to 
 waste. Its productive capacity and selling value would be quadrupled 
 if "moisture can be supplied at will, instead of being left to chance," 
 and the rising values of both land and water will now permit of the 
 expenditure to do this. 
 
 Each new area brought under irrigation, each new increase in the 
 water taken from streams or lifted from under-ground supplies, gives 
 rise to new questions regarding water titles and adds to the impor- 
 tance of canal management. Hence, while our knowledge of irriga- 
 tion is constantly extending, we are also constantly being confronted 
 with new problems which have to be solved. Those most familiar with 
 irrigation and most skilled in its practice find in its changing condi- 
 tions a constant field for study, while beginners find that the difference 
 
between irrigated agriculture and agriculture dependent on rainfall 
 requires of them a knowledge of many things wholly new and strange. 
 
 A large percentage of the lands being brought under irrigation are 
 being settled by men from humid sections of the country who must 
 learn in some way how to grade their fields, how to lay out laterals, 
 how much water is needed, and how often to use it. California is 
 vitally interested in these farmers becoming skillful users of water in 
 the shortest possible time. Too much water is almost as bad as too 
 little. Wasteful use by one irrigator often ruins his neighbor's crop 
 and injures his own. The injury from alkali is chiefly due to wasteful 
 or unskillful use of water. 
 
 It is believed that the University of California can aid in the gen- 
 eral improvement of irrigation practice by extending the work now 
 being done in the class-room. This includes instruction in Irrigation 
 Engineering, Irrigation Institutions, and Irrigation Practice. We 
 have decided to offer reading courses in Irrigation Institutions and 
 Irrigation Practice. Under Irrigation Institutions are included the 
 business and financial methods under which canals are built, how the 
 rights to the water which fills them are acquired, and the conditions 
 and terms on which irrigators are supplied. Irrigation Practice will 
 include descriptions of the methods of preparing land for irrigation, 
 the cost of such preparation, the results of measurements to determine 
 the amount of water used in irrigation and the factors which influence 
 it, and description of the methods of irrigation employed in California, 
 for fruit growing, fields, and gardens. 
 
 Those desiring to enroll themselves as readers should make appli- 
 cation to W. T. Clarke, Assistant Superintendent, University Exten- 
 sion in Agriculture, Berkeley, California. Each reader will be fur- 
 nished with a text-book in the branch of the subject which he desires 
 to study. He will be expected to make himself thoroughly familiar 
 with its contents. A circulating library is also provided for collateral 
 reading and reference. These books should be read as carefully as 
 possible, in accordance with the directions given in this circular. After 
 the completion of the work here outlined, an examination will be ar- 
 ranged with some one connected with the Department of Irrigation 
 Institutions and Practice. 
 
 These courses may be considered a University course given in ab- 
 sentia, and must be pursued with the same care and thoroughness as 
 though done in the class-room in Berkeley. The names of those com- 
 pleting these courses will be kept as a special mailing list ; and they 
 
will receive thereafter, not only the bulletins of the Experiment Sta- 
 tion, but all circulars and notices of special publications on irrigation 
 issued by the United States Department of Agriculture. Those read- 
 ing in these courses by themselves will receive the books forming the 
 reference library, one at a time, by express, and will be required to pay 
 the express charges both ways. There will be no fees or other charges 
 to be paid by the students, except for damage to books beyond reason- 
 able wear. The Irrigation Department will attempt to answer letters 
 of inquiry of readers in this course, and to assist them in any questions 
 they may find in their studies. 
 
 Reading Circle. — It is strongly recommended that wherever pos- 
 sible a reading circle be formed for mutual helpfulness in this study. 
 Where this is done, the whole reference library will be sent to the 
 member designated by the circle, and the distribution can be arranged 
 to suit the convenience of the members. We would suggest that the 
 circle form an organization, changing a sum for membership sufficient 
 to raise a fund not only to pay the express charges on the circulating 
 library, but also to buy a few books on the subject for the local library 
 or as a nucleus for a public library, if one is not already in existence 
 in the community. Thus the work of the circle will become more per- 
 manent. 
 
 Another advantage of the organization of a reading circle will be 
 the possibility of personal instruction by a visit, to the community, of 
 a member of the staff of the Irrigation Department. Where possible, 
 some such arrangement as the following will be made : After the com- 
 pletion of the course by the circle, a date will be arranged for this visit ; 
 and if provision can be made for the projection of pictures on a screen, 
 the instructor will come prepared to give an illustrated lecture com- 
 paring California's irrigation methods with those of other countries. 
 The instructor will also come prepared to give a day to considering 
 with his class the local problems of interest or importance. 
 
 Those who enroll as students will be expected to make reports of 
 their progress, and in these reports to bring out the relation of what 
 they are reading to local conditions or practice. This will aid the in- 
 structor in making suggestions as to further studies. Comparisons 
 by the reader of local practice or local problems with the description 
 and discussion of the text will give life and interest to the work. In 
 addition the reader should seek to arrive at independent conclusions 
 as to both the institutions and practice needed to secure the best de- 
 velopment of irrigated agriculture in his section. To this end it is sug- 
 
gested that each reader prepare at the beginning* of his course a set of 
 questions which embrace the things of greatest interest to him person- 
 ally. The following list is suggestive of what these may embrace : — 
 
 IRRIGATION PRACTICE. 
 
 1. Is check irrigation suited to mixed farming and rotation of crops? 
 
 2. What plan of applying water in irrigation is adapted to the largest number 
 
 of crops, and hence to the adoption of a rotation system? 
 
 3. Which is better suited to the irrigation of orchards, checks or furrows? 
 
 4. How often should orchards be irrigated? 
 
 5. How often should alfalfa be irrigated, and when? 
 
 6. Does it pay to irrigate small grain? 
 
 7. What are the benefits of winter irrigation, and can crops be grown by winter 
 
 irrigation alone? 
 
 8. Is seepage water or alkali a menace? 
 
 9. If so, when do its ill effects begin to be manifest, and what are the causes? 
 10. Is complete under-drainage feasible? If so, at what depth should the drains 
 
 be laid? 
 
 IRRIGATION INSTITUTIONS. 
 
 1. What is the proper foundation for water titles — riparian rights, appropria- 
 
 tions, or licenses issued by the State? 
 
 2. Should water rights for irrigation be attached to the land irrigated? 
 
 3. Should there be an official State record of water titles? 
 
 4. Should charges for water be based on the acres irrigated, or on the quantity 
 
 of water used? 
 
 5. Which are more efficiently managed — canals operated by water companies, or 
 
 canals operated by farmers? 
 
 6. What is the most convenient unit of volume for the delivery of water — the 
 
 inch, the cubic foot per second, the gallon, or the acre foot? 
 
 7. What volume of water will give the best return from an acre of land? What 
 
 volume will give the highest return from the acre foot of water? 
 
 8. What is the better practice in irrigation — to apply water with the object of 
 
 securing the largest return from the land, or the best return from a unit 
 volume of water? 
 
 9. What is the value of water for winter irrigation? What is its value for 
 
 summer irrigation? 
 
 The books included in this course bring together the results of 
 practical experience and scientific observation in widely separated 
 sections of the country, and it is believed will aid in determining what 
 is best suited to the widely varying conditions of this State. It is also 
 hoped that it will contribute to bringing about a clearer understanding 
 
of the complex and important water problems of California which 
 have been created by the increasing needs of users for irrigation, the 
 growing consumption of water by cities and towns, and its augmented 
 value for power purposes. The protection of existing rights, the ad- 
 justment of rival and conflicting claims of the different classes of 
 users, and the wise direction of future development, make the manage- 
 ment of the water resources of California its most important indus- 
 trial issue. 
 
 INSTKUCTION IN IEEIGATION AT BEEKELEY. 
 
 For the information of those who desire to continue their studies 
 in Irrigation at the University, it may be stated that a complete course 
 in Irrigation Engineering is given. The courses given by the Depart- 
 ment of Irrigation and the courses in the College of Agriculture most 
 directly related to Irrigation are as follows : — 
 
 1. Irrigation Institutions and Economics. Professor Mead. 
 Present conditions of irrigation in the United States; irrigation legislation; 
 
 methods of establishing rights to water; inter-state problems; conditions 
 necessary to development of the agricultural resources of the arid West; 
 comparisons of irrigation methods and laws of other lands with those of the 
 United States; irrigation in humid sections of the United States; operation 
 of irrigation works, individual, cooperative and corporate enterprises; na- 
 tional irrigation; water right contracts; duty of water. Lectures and reci- 
 tations. 
 
 2. The Diversion, Conveyance, and Application of Water. 
 
 Professor Etcheverry. 
 Properties of water; units of measurement; flow of water through orifices, 
 over weirs and in open and closed channels; gauging laterals, canals, and 
 streams by means of floats, current meters, weirs, modules ; irrigation works 
 classified; diversion weirs and headgates; alignment, slope and cross-section 
 of canals; suitable grades for required velocities; construction and mainte- 
 nance of canals; flumes and pipes for irrigation, their construction and use; 
 methods of applying water to land; duty of water. Full illustrations by 
 lectures and practical problems. 
 
 2a. Irrigation Design. Professor Etcheverry. 
 
 The design of irrigation structures, such as headgates, flumes, and drops. Prep- 
 aration of detailed estimates of cost of such structures. 
 
 3. The Conservation of the Water Supplies. Professor Etcheverry. 
 Sources of water supply; precipitation, run-off and fluctuation in stream-flow; 
 
 loss of water by evaporation and seepage; return waters; removal of sur- 
 plus and seepage waters; reclamation of alkali lands by means of drainage; 
 
storage of water in natural lakes and artificial reservoirs; utilization of 
 subterranean sources of supply by means of pumps, drains, tunnels; con- 
 servation of soil moisture; influence of forests on water supply. 
 
 4. Drainage. Professor Etcheverry. 
 
 Structure of soil and its relation to drainage; necessity for drainage; its ef- 
 fects on the soil; ground water and its flow; laying out drains; distance 
 between; depth of, grade of; size of tile; kinds of drains; drainage sys- 
 tems and districts; estimates of cost. 
 
 AGEICULTUEE. 
 
 1b. Chemistry and Physics of Soils. 
 
 Professor Hilgard and Assistant Professor Loughridge. 
 Origin, formation, and classification of soils. Physical properties and mechan- 
 ical analysis; chemical composition. Soil analysis — its methods, utility, 
 and interpretation. Policy of culture; exhaustion of soils and their fertil- 
 ization and restoration; drainage, irrigation, soils of the arid and humid 
 regions; soil regions of the Pacific coast. 
 
 4a. Agriculture. Professor Wickson. 
 
 Field cultures of grains, vegetables, and forage plants. 
 
 4b. Horticulture. Professor Wickson. 
 
 Principles and practice of fruit growing in semi-tropical countries, with special 
 reference to California conditions and methods. 
 
 Suggestions for Readers in Irrigation Courses. 
 
 IRRIGATION PRACTICE. 
 Volume 1. — Text-book. 
 Volume 2. — Collateral reading: King on Irrigation and Drainage. 
 
 The text-book in Irrigation Practice is made up from a series of 
 bulletins, the larger part of which were prepared by members of the 
 station staff or professors in the University of California. 
 
 It begins with a description of the methods and tools used in pre- 
 paring land for irrigation and the methods of applying water to crops. 
 This is followed by a description of some of the home-made devices by 
 which farmers can lay out their own laterals. 
 
 Next comes a discussion of irrigation practice with special relation 
 to conditions in California, and includes irrigation in field and garden, 
 irrigation in fruit growing, and the results of the irrigation of orchards 
 on the Pacific coast. This portion of the text will give an understand- 
 ing of the principles which underlie irrigation practice in California, 
 so far as the preparation of land and application of water are con- 
 
cerned. The reader is then prepared to take up the study of the spe- 
 cial methods and practices employed in different parts of the State. 
 Those given are from the Southern and Central portions of California. 
 
 The summary of investigations of the amount of water used 
 throughout the United States, which follows, is intended to aid the 
 reader in reaching a conclusion as to the area which can be served by 
 the water supply of his section. The concluding pages of the bulletin 
 deal with some of the evils of irrigation and the methods by which 
 they may be overcome. The two chief evils — the swamping-up of the 
 lower lands of the irrigated territory, and the accumulation of alkali 
 in the surface soil — both have their origin in seepage waters. This is 
 followed by the results of some of the alkali and drainage studies made 
 in the State. 
 
 As collateral reading for the text-book, Chapter III, King's work 
 on Irrigation and Drainage, published by Macmillan & Co., pages 131 
 to 170 and pages 269 to 289, may'be read with profit. 
 
 IRRIGATION INSTITUTIONS. 
 
 Volume 1. — Text-book: Irrigation Institutions, by Mead, published by Macmillan 
 & Co. 
 
 •Volume 2. — A Report on Irrigation in California, published by the Office of Ex- 
 periment Stations, United States Department of Agriculture. 
 
 Volume 3. — Canal and Stream Management. 
 
 The course in Irrigation Institutions is intended to give an under- 
 standing of the legal antl economic principles which govern the man- 
 agement of streams and the distribution of water from canals in the 
 states where irrigation has assumed large importance. The text gives 
 an outline of the evolution of these laws and customs. 
 
 Volume 2 describes the conditions prevailing in some of the valleys 
 of California. Volume 3 gives some examples of canal management in 
 a number of the Rocky Mountain states, and follows this with a de- 
 scription of the methods for acquiring rights from streams and the 
 division of water between those holding these rights. 
 
 For information concerning Instruction in Irrigation at the Uni- 
 versity of California, address B. A. Etcheverry, Assistant Professor of 
 Irrigation, Berkeley, California. 
 
 For information concerning reading courses in Irrigation, address 
 Mr. W. T. Clarke, Department of University Extension in Agricul- 
 ture, Berkeley, California,