UNIVERSITY OF CALIFORNIA COLLEGE OF AGRICULTURE AGRICULTURAL EXPERIMENT STATION BERKELEY, CALIFORNIA RICE EXPERIMENTS IN SACRAMENTO VALLEY 1922-1927 CARROLL F. DUNSHEE Experimental field at Cortena just after submergence BULLETIN 454 MAY, 1928 UNIVERSITY OF CALIFORNIA PRINTING OFFICE BERKELEY, CALIFORNIA 1928 Digitized by the Internet Archive in 2012 with funding from . University of California, Davis Libraries http://www.archive.org/details/riceexperimentsi454duns RICE EXPERIMENTS IN SACRAMENTO VALLEY 1922-1927 CARROLL F. DUNSHEEa This bulletin 2 presents a progress report of rice experiments carried on by the Division of Irrigation Investigations and Practice, University of California, at the temporary rice field station near Cortena since 1922; also, a summary of measurements of the duly of water in rice irrigation in 1924 and 1925. Detailed reports of the results obtained at Cortena during 1922 and 1923 appeared as bulletins 354 and 375 of the University of California Agricultural Experiment Station. The experiments at Cortena were started in 1922, following requests from the rice growers for information on methods of weed control. At that time the growers were especially concerned over the control of the barnyard grass or water grass (EchinocJiloa crus-galli). There was no satisfactory method generally practiced for the control of this weed, although a few growers were obtaining fairly good results from submerging the rice at time of planting. For this reason the experiments outlined covered a series of cultural and depth-of- submergence tests to determine the most satisfactory method of con- trolling the water grass, as well as other weeds prevalent in the rice fields. In addition to these experiments, a study was started to deter- mine the best date of seeding and the effect of fallow on the yield of rice. The land at Cortena was first planted to rice in 1918 and farmed each year through 1921, at which time it was abandoned by the lessees 1 Assistant Crop [rrigationist, Division of Irrigation Investigations and Prac- tice. -Based on data gathered in part in cooperation with the Office of Cereal Crops and Diseases, Bureau of Plant [ndustry, T. S. Department of Agriculture; and in part in cooperation with the Division of Agricultural Engineering, T T . S. De- partment of Agriculture, and the Division of Water Rights, California Depart- ment of Public Works. Responsibility for the rice investigations referred to in this bulletin lies with the Division of Irrigation Investigations and Practice, but that Dvision has the advantage of the advice, in planning the investigations from year to year, of tlie following Rice Committee appointed by the Director of the Experiment Station: Prank Adams, Chairman; P. L. Hibbard, J. W. .tones (Superintendent of the Biggs Rice Field station of the Bureau of Plant [ndustry), P. B. Kennedy, W. W. Mackie, C. F. Shaw, W. W. Weir, and E. J. Stirniman. " 4 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION because of the presence of water grass, cat-tails (Typha latifolia), and other rice weeds. This area was selected for the experimental work because it was particularly foul and situated on Willows clay adobe soil, which is representative of a large area devoted to rice culture on the west side of the Sacramento Valley. The series of experiments outlined to determine the best method of weed control, while still producing satisfactory yields, were as follows : 1. Broadcasting 150 pounds of seed per acre on well prepared seed bed, and submerging immediately to depths of 4, 6, and 8 inches, continuing the submergence throughout the season. 2. Drilling seed at the rate of 150 pounds per acre and submerg- ing immediately to depths of 4, 6, and 8 inches, continuing submergence throughout the season. 3. Drilling seed at the rate of 150 pounds per acre and submerg- ing to depths of 4, 6, and 8 inches after the rice had sprouted and was about 1 inch high. 4. Broadcasting 150 pounds of seed per acre in water held at depths of 4, 6, and 8 inches. 5. Effect of seed bed preparation on the control of weeds and the yield of rice. In this series the land was not plowed, the seed being sown broadcast at the rate of 150 pounds per acre on the old rice stubble. Supplementing the above studies a series of experiments were conducted to determine the proper time of seeding. METHOD OF SEEDING The results of the work at Cortena, and at the Biggs Rice Field Station conducted by the United States Bureau of Plant Industry, where similar studies were under way, 3 showed conclusively that of the four irrigation and seeding treatments tried, that of broadcasting and submerging the seed to depths of six to eight inches held the most promise. A summary of the results obtained at Cortena is given in table 1. 3 Jones, Jenkin W., Experiments in rice culture at the Biggs Eice Field Station in California. U. S. D. A. Dept. Bui. 1387: 1-39. 1926. BUL. 454] RICE EXPERIMENTS IN SACRAMENTO VALLEY, 1922-1927 5 TABLE 1 Summary of Kesults at Cortena Showing Effects of Methods of Seeding and Depths of Submergence on Weed Control and Yields of Bice, 1922-1924 Weed control Yields in pounds of rice per acre for various methods of seeding Depth of Drilling Broadcasting in inches Seed sprouted before submerging Seed submerged immediately Seed submerged immediately Seeded in water 4 6 8 Part control Clean Clean 1,212 1,606 1,958 1,167 1,062 1,782 2,149 2,812 2,813 2,271 1,812 2,247 DATE OF SEEDING The results from the first experiments conducted to determine the best date of seeding indicated very clearly that the highest yields could be expected from the earliest date of seeding. It was, therefore, the aim in succeeding tests to seed first on April 15, but due to late spring rains it has been possible to do this only one year. Rice planted on June 1 was a week or ten days later in maturing than that of the earlier seeding. There were many more immature kernels on the panicles than on that seeded earlier. The results are shown in table 2. TABLE 2 Results at Cortena on Date of Seeding, 1922-1923 Method of seeding Yields of rice in pounds per acre Date 1922 1923 Average April 25* Broadcast 1 and immediate 1 6-inch submergence [ 3,664 2,558 2,648 2,069 2,788 2,338 2,388 1,137 3,226 May 1 May 15 2,448 2,518 1,603 * April 15 in 1922. EFFECT OF SEED BED PREPARATION ON WEED CONTROL The experiments on the effect of plowing on weed control show definitely that it is necessary to plow deep enough to turn the cat-tail roots up to the sun during the period of seed bed preparation. In the plots which were plowed each year, the cat-tail growth was satis- factorily controlled, and indeed, there have been fewer cat-tail plants appearing each succeeding year. Such cat-tail plants as have b UNIVERSITY OF CALIFORNIA — EXPERIMENT STATION appeared have been pulled during July. The cost of pulling has not averaged more than seventy-five cents an acre per year during the period the experiments have been under way. Four plots having a total area of three acres were not plowed, the seed being broadcast on the rice stubble at the rate of 150 pounds per acre, and submerged immediately to a depth of six inches. The growth of cat-tail, joint grass (Paspalum distichum) and spike rush (Eleocharis palustris) became very thick, resulting in low yields. ' In 1922 the average yield amounted to 1368 pounds per acre, while in 1923 this area was so foul at harvest time that it was impossible to cut the rice. The area was again planted to rice in 1924, and because of the dense weed growth the rice was bound with considerable difficulty in the fall. The yield that year averaged 632 pounds per acre. During 1925 and 1926 these plots were plowed each spring and fallowed. They were again plowed in the spring of 1927 and seeded to rice at the rate of 150 pounds per acre. The control of the cat-tail and other weeds was very satisfac- tory, the cost of pulling those plants which did grow amounting to $1.65 an acre. The yields obtained were excellent, averaging 4460 pounds to the acre. EXPERIMENTS UNDER WAY SINCE 1924 Following the season of 1924 a cooperative agreement relating to rice investigations was made between the Office of Cereal Crops and Diseases, Bureau of Plant Industry, U. S. Department of Agriculture, and the California Agricultural Experiment Station. It was decided at that time to conduct the main experimental work with rice at the Biggs Station, and use the Cortena Station to study the effect of continuous rice growing on the yield of rice, the control of weeds, and on the physical, chemical, and biological condition of the soil. It was also decided to test out at Cortena certain of the methods tried at Biggs which appeared to be of practical value ; among these being the use of ammonium sulphate as a rice fertilizer. With this in view the entire area at Cortena has been managed according to the best practice determined during the years 1922 to 1924. Each year a fine seed bed has been prepared, the seed broadcasted on the surface at the rate of 150 pounds per acre, and the whole area submerged immediately to depths varying between six and eight inches. It has been the practice to seed as early in the spring as possible, but the dale has been delayed at limes until ]\hry 15, due to late rains. The frontispiece shows a view of a portion of the experimental area just after submergence. BUL. 454] rice EXPERIMENTS IN SACRAMENTO VALLEY, 1922-1927 7 The north half of the field was fallowed in 1924, but was rechecked and planted to rice again in 1925. It was noticeable during the course of seed bed preparation that this area was in considerably better physical condition than before the year of fallow. Where there had been a few cat-tail plants on this area during the two preceding years, none appeared during the 1925 season. There was a slight increase in yield in this area over the yield received from the south half of the field during 1925 and 1926. It is probable that this increase may be attributed to the beneficial effects of the fallow. However, in 1927 the average yield from the south field was con- siderably more than the average yield from the field fallowed in 1924. USE OF AMMONIUM SULPHATE AS A RICE FERTILIZER The results from the use of ammonium sulphate at Cortena have shown an increase in the yield of rice in favor of the fertilized plots each year. During 1925 and 1926 the fertilizer was applied at the rate of 100 pounds per acre with the result that the average increase in yield over the unfertilized area was approximately 800 pounds per acre in 1925 and approximately 500 pounds per acre in 1926. Due to the results obtained at the Biggs Station over a period of years, which indicated that 150 pounds per acre was the most econom- ical rate of application, the rate at Cortena was increased to 150 pounds per acre in 1927. That year the increase in yield in favor of the fertilized plots was approximately 1200 pounds per acre. Inasmuch as the cost of the fertilizer, plus application, has never amounted to more than $5.50 per acre, the use of this fertilizer appears to be an economical procedure. The results obtained from the use of ammonium sulphate since 1924 are summarized in table 3. TABLE 3 Eesults Obtained from Fertilizing Rice Fields with Ammonium Sulphate, at Cortena, 1925-1927 Year Date of seeding Treatment Area, acres Yield per acre 1925 May 15 ( May 10 j Unfertilized 18.57 3.10 18 43 3.10 20 03 3 10 2,797 3,585* 1926 2,343 May 1 j 2,846* 1927 Unfertilized Fertilized 3,288 4,486t * Fertilized at the rate of 100 pounds to the acre. t Fertilized at the rate of 150 pounds to the acre. UNIVERSITY OF CALIFORNIA EXPERIMENT STATION WEED CONTROL BY CONTINUOUS SUBMERGENCE^ Summarizing the observations on weed control, the studies at Cortena show that continuous submergence to depths of 6 to 8 inches after the rice is sown broadcast will satisfactorily control most of the various types of water grass and will result in good yields. This method will also control the sprangle top (Leptochloa fascicularis) . However, continuous submergence will not control the late white water grass, which matures its seed in September and October. The Fig. 1. — Bice grown under continuous submergence method. Note absence of water grass between levees in left foreground. (From Bui. 354.) only method of control known is to pull these weeds as they appear in the field. If the white water grass is not controlled it will result in reduced yields, and also in a lower grade of rice, unless it is re- cleaned before being placed on the market. Figure 1 indicates the extent of control of water grass when the continuous submergence method is practiced. Sedge (Cy penis difformis), red stem (Ammania coccinea), arrow- head (Sagittaria latifolia), and the water plantain (Alisma plan- tag o) can usually be satisfactorily controlled with a thick stand of rice which has been planted as early in the spring as possible. In 4 A discussion of the rice weeds of California has appeared in: Kennedy, B. B., Observations on some rice weeds in California. California Agr. Exp. Sta. Bui. 356: 467-494. 1928. Bul. 454] RICE EXPERIMENTS IX SACRAMENTO VALLEY, 1922-1927 9 order to insure a thick stand of rice at least 1")0 pounds of well matured seed should be sown on a smooth seed bed. The cat-tail (Typha Jafifolia) can be satisfactorily controlled, pro- viding the soil is well plowed each spring and the roots are allowed to dry four or five days before preparing the seed-bed. This must be followed by pulling the plants which do grow. It appears that the best time to pull cat-tails is during the month of July. This is suf- ficiently late to be sure that few plants will appear later in the season, and early enough so that the rice will not be damaged by tramping on it while it is in the boot. Where fields have become foul due to poor farming it may be necessary to fallow the land for one or two years before the cat-tail growth can be satisfactorily controlled. Joint grass (Paspahim dktichum) can be controlled by fallow for a year or two after the fields become so foul with this weed that the further production of rice is not economical. The weed usually starts from the levees and after a few years the runners may be found fifty or seventy-five feet out in the rice field. Wire grass or spike rush (Eleocharis palustris) can be satisfac- torily controlled by a thorough plowing in the spring. If the roots of this weed are turned up to the sun to dry for four or five days, very few of the plants will survive. It is usually only in the corners of the field that this weed is at all troublesome. COMPARISON OF AIR AND WATER TEMPERATURES It is believed by some growers that during periods of cool weather the soil can be warmed by withdrawing the irrigation water for a few days. In order to make a comparison of the air and water temperatures during the growing season, a thermograph record of the water temperatures was kept, beginning in 1924. An air thermo- graph was installed at the time the station was started. The torpedo of the thermograph recording the water temperatures was placed on the soil surface under six inches of water and was some eight feet out in the rice check, the recording machine being placed on the levee. The air thermograph was placed in a Standard Weather Bureau shelter house. The records of these two instruments show that during May the average maximum water temperature was always as high, and at times higher, than the average maximum air temperature. The average minimum water temperature was always higher than the average minimum air temperature. However, as the rice grows taller and shades the water, the maximum temperature of the water falls below the maximum air temperature. 10 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION DUTY OF WATER IN RICE IRRIGATION During the irrigation seasons of 1924 and 1925 studies were car- ried on to determine the use of water in rice irrigation under the practice of all-season submergence. Previous to those years studies had been conducted on the use of water under the method of "flush- ing" the field from four to six times prior to permanent submergence. 5 They show a net use varying from 3.94 acre-feet to the acre on what are known in the soil surveys as Capay clay soils, to 10.94 acre-feet to the acre on the San Joaquin loam soils. On the clay, clay adobe, and adobe soils, which are the usual rice soils in the Sacramento Valley, the net use varied between 3.91 and 5.72 acre-feet per acre. Since the method of continuous submergence from time of plant- ing was becoming a general practice on old land, the studies con- ducted in 1924 and 1925 were intended to determine the difference in water requirement, if any, due to all-season submergence. Theo- retically, providing the length of the irrigation season is the same, continuous submergence should result in a larger use than submergence beginning several weeks after seeding. The longer period of sub- mergence should result in greater loss through seepage, evaporation, and waste over the tail gate. However, the results obtained during 1924 and 1925 showed practically the same use as obtained with the earlier method. This may be due to the fact that earlier maturing varieties are now being planted, and the method of continuous sub- mergence further hastens the maturity of rice by several days. In 1916, 1917 and 1918 the length of the irrigation season varied from 139 to 189 days, with the irrigation season on the majority of the fields, more than 155 days. In 1924 and 1925 the length of the irri- gation season varied from 109 to 146 days, with only two fields exceed- ing 140 days. Six fields were studied in 1924, the total area being 1200.49 acres. The individual fields varied in size from 63 to 612.9 acres. These fields were located on the west side of the Sacramento Valley, from Williams north to Willows, and covered the range of soil types on which rice is most generally grown in this area. Measurements of delivery to the fields were made with submerged orifices, carefully standardized, while the drainage water was measured over rectangular weirs. Automatic water-stage registers, visited daily throughout the season, recorded the flow in both cases. Typical installations of these devices are shown by figures 2 and 3. In all, 27 water-stage registers 5 Adams, Frank. Rice irrigation measurements and experiments in Sacramento Valley, 1914-1919. California Agr. Exp. Sta. Bui. 325: 47-69. 1920. Bul. 454] RICE EXPERIMENTS IN SACRAMENTO VALLEY, 1922-1927 11 were necessary. At the close of the season, yields produced on all fields under observation were obtained and are included in the tables given below. However, yields are influenced so much by the human factor and the elements that they can not be directly correlated with amounts of water used. The results of the 1921 season show a net use ranging 1 from 4.20 acre-feet per acre on the Willows clay adobe soils Fig. 2, Typical submerged orifice used in measuring delivery of water to rice fields, 1924. H\\\W W I Fig. 3. — Typical rectangular weir used in measuring drainage watei from rice fields, 1924. 12 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION to a net use of 7.41 acre-feet per acre on the Willows loam soils. The average net use on the Willows clay and clay adobe amounted to 4.81 acre-feet to the acre. Two fields were studied in 1925, one field of 112 acres being located near Cortena on Willows clay soil, and the other field, comprising 38.8 acres, was on Stockton clay adobe soil adjacent to the Biggs Rice Field Station. The same procedure followed in 1924 was continued during 1925. The Armstrong field at Biggs was formerly farmed by Mr. E. L. Adams and measurements of use of water were made on this field from 1914 to 1917, inclusive, under the old method of flushing several times before submerging the field permanently. It is interesting to note that the net use on this field in 1916 was 4.27 acre-feet to the acre, and in 1917 the net use was 4.37 acre-feet to the acre, the average use for the four seasons having been 4.53 acre-feet to the acre. In 1925, under the continuous submergence method, the net use amounted to 4.88 acre-feet to the acre. This increased use may be due to the fact that since 1918 deep drains have been constructed on two sides of the field. The irrigation season in 1916 amounted to 171 days and in 1917 to 164 days, while in 1925 the length of the irrigation season was 134 days. The results of the work in 1925 show that on the Willows clay adobe the net use was 4.27 acre-feet to the acre, while on the Stockton clay adobe the net use was 4.88 acre-feet to the acre. In tables 4 and 5 are included summaries of the data obtained on the use of water during 1924 and 1925. TABLE 4 Duty of Water for Eice on Eight Fields Under All-season Submergence, 1924-1925 Year Grower Acreage Total intake, acre-feet Total measured drainage, acre-feet Total lost over levees, acre-feet (estimated) Acre-feet on field at date of draining (estimated) Variety of rice Yield, pounds per acre 1924 H usted 63.28 492.00 129.91 None 21.09 Onsen 2,978 1924 Yarborough 102.38 532.21 92.71 9.30 34.12 Caloro 2,780 1924 Rathbun 111.67 789.93 212.70 None 27.91 Onsen 2,770 1924 Bruggman 109.41 734.19 163.69 64.87 27.35 Caloro 2,496 1924 Goepf 200.85 1,653.48 63.53 None 100 43 Caloro 2,275 1924 Jones 612.90 5,109.08 587.67 None 204 30 f Early (Wataribune 1,028* 1925 A nderson 112.05 651.25 119.30 None 56 1,600 2,699 1925 Armstrong 38.8 318.83 129.40 None Drainage all measured Caloro 3,200 Based on area irrigated; 1,139 pounds, based on area harvested. « o CO to cn CO to Cn - EC •*- 1924 1924 CO co to to 4» 4- P Moore Yarborough Hotaling S.V.S.F.L.Co. Minor Ranch Barcelaux Esperanza Land Co. Armstrong o J; 3 re -i Husted Yarborough Rathbun Bros. Bruggman Goepf Jones Anderson and Bank of Williams Armstrong Grower Willows clay Willows clay Willows clay adobe Willows clay adobe Willows loam Willows loam and Willows clay adobe Willows clay adobe Stockton clay adobe Soil classification from soil maps of U. S. D. A., Bureau of Soils 63.28 102.38 111.67 109.41 200.85 612.90 112 05 38.8 p >► re a co to co >*». co o rf^to »*•• 4^ CO CO ^1 CO O Oi Irriga- tion season, days 7.78 5.19 7.06 6.67 8.23 8.34 5.81 8.21 H o p. p go Ts re re' c<- CL3- "pS, 3* ll re re re i 5.72 4 20 5.03 4.67 7.41 7 09 4.27* 4.88J 2 re •** OS CO Average net for soil type 12.65 24.90 27 33 34 51 30.67 35.53 19.44 7.87 During submer- gence, acres co re re p h - re re 2 c cr S£ eg CO c+ re 47.22 78.15 48.55 67.45 36.72 35.74 56.87 58.79 From submer- gence to end of season, acres 43.35 68.57 42.79 57.88 35.89 35.69 51.63 53. 29* For whole season, acres Cn to OO o Cn Cn OO Average whole season for soil type, acres 46.18 74.73 45 21 62.52 38.18 37 39 57.73 53.29* 3 Acres served per cubic foot per second based on total intake, less measured drainage and less acre-feet of water on field on date of draining Cn Cn O co o cn > ^Tp ■*■ k * 3 14 UNIVERSITY OF CALIFORNIA EXPERIMENT STATION SUMMARY AND CONCLUSIONS 1. Rice sown broadcast at the rate of 150 pounds per acre and immediately submerged six to eight inches deep will produce satis- factory yields on old land, providing Avell matured seed is used and planted as early in the spring as possible on a well prepared seed bed. 2. The continuous submergence of rice to depths of six to eight inches will control sprangle top and the earlier maturing types of water grass. 3. Continuous submergence will not control the late white water grass. This weed should always be pulled where it is economically possible to do so. 4. Deep plowing in the spring will aid in the control of cat-tail plants, provided the up-turned roots are allowed to become thoroughly dry before preparing the seed bed. Any of these plants that are not killed by this treatment should be pulled during July. 5. The detrimental effects of such weeds as sedge, red stem, arrow- head and water plantain are materially reduced by thick stands of rice. 6. Joint grass can usually be controlled by a year or two of dry fallow. 7. Spike rush can be satisfactorily controlled by a thorough spring plowing, provided a period of drying weather follows. 8. On old land which is not producing more than 3000 pounds to the acre it is an economical practice to apply 150 pounds of am- monium sulphate to the acre just prior to seeding. 9. An occasional year or two of fallow will aid in bringing the soil into better physical condition ; will help in controlling such weeds as cat-tails, joint grass and spike rush ; and will probably result in some increase in the yield of rice. 10. The minimum water temperature during the growing season is always somewhat higher than the minimum air temperature. Prom these studies the conclusion may be drawn that from the standpoint of "warming up the soil" there is nothing to be gained by withdraw- ing the water for a few days. 11. Studies carried on in 1924 and 1925 show that under the method of continuous submergence the net duty of water for rice should not amount to more than 5 acre-feet to the acre on the clay, clay adobe or adobe soils. On the loam soils the net duty may amount to as much as 8 acre-feet to the acre. STATION PUBLICATIONS AVAILABLE FOR FREE DISTRIBUTION No. 253. Irrigation and Soil Conditions in the Sierra Nevada Foothills, California. 262. Citrus Diseases of Florida and Cuba Compared with those of California. 263. Size Grades for Ripe Olives. 268. Growing and Grafting Olive Seedlings. 273. Preliminary Report on Kearney A' ine- yard Experimental Drain, Fresno County, Calif. 277. Sudan Grass. 278. Grain Sorghums. 279. Irrigation of Rice in California. 283. The Olive Insects of California. 304. A Study of the Effects of Freezes on Citrus in California. 310. Plum Pollination. 313. Pruning Young Deciduous Fruit Trees. 324. Storage of Perishable Fruits at Freez- ing Temperatures. 328. Prune Growing in California. 331. Phylloxera-resistant Stocks. 335. Cocoanut Meal as a Feed for Dairy Cows and Other Livestock. 340. Control of the Pocket Gopher in California. 343. Cheese Pests and Their Control. 344. Cold Storage as an Aid to the Mar- keting of Plums, a Progress Report. 347. The Control of Red Spiders in Decid- uous Orchards. 348. Pruning Young Olive Trees. 349. A Study of Sidedraft and Tractor Hitches. 350. Agriculture in Cut-Over Redwood Lands. 353. Bovine Infectious Abortion, and As- sociated Diseases of Cattle and New- born Calves. 354. Results of Rice Experiments in 1922. 357. A Self-Mixing Dusting Machine for Applying Dry Insecticides and Fun- gicides. 358. Black Measles, Water Berries, and Related Vine Troubles. 361. Preliminary Yield Tables for Second- Growth Redwood. 362. Dust and the Tractor Engine. 3 63. The Pruning of Citrus Trees in Cali- fornia. 364. Fungicidal Dusts for the Control of Bunt, 366. Turkish Tobacco Culture, Curing, and Marketing. 367. Methods of Harvesting and Irrigation in Relation to Moldy Walnuts. 368. Bacterial Decomposition of Olives During Pickling. 369. Comparison of Woods for Butter Boxes. 370. Factors Influencing the Development of Internal Browning of the Yellow Newton Apple. 371. The Relative Cost of Yarding Small and Large Timber. 373. Pear Pollination. 374. A Survey of Orchard Practices in the Citrus Industry of Southern California. :',7"). Results of Rice Experiments at Cor- tena, 192:5, and Progress in Experi- ments in Water Grass Control al the Biggs Rice Field Station, 1922-23. 377. The Cold Storage of Pears. 379. Walnut Culture in California. 380. Growth of Eucalyptus in California Plantations. 382. Pumping for Draininge in the San Joaquin Valley, California. 385. Pollination of the Sweet Cherry. BULLETINS No. 3 86. 387. 388. 389. 390. 391. 392. 393. 394. 395. 396. 397. 398. 400. 402. 404. 405. 406. 407. 408. 409. 411. 412. 414. 415. 416. 418. 420. 421. 422. 423. 425. 426. 427. 429. 430. 431. 432. Pruning Bearing Deciduous Fruit Trees. Fig Smut, The Principles and Practice of Sun- Drying Fruit. Berseem or Egyptian Clover. Harvesting and Packing Grapes in California. Machines for Coating Seed Wheat with Copper Carbonate Dust. Fruit Juice Concentrates. Crop Sequences at Davis. I. Cereal Hay Production in Cali- fornia. II. Feeding Trials with Cereal Hays. Bark Diseases of Citrus Trees in Cali- fornia. The Mat Bean, Phaseolus Aconitifo- lius. Manufacture of Roquefort Type Cheese from Goat's Milk. Orchard Heating in California. The Utilization of Surplus Plums. The Codling Moth in Walnuts. The Dehydration of Prunes. Citrus Culture in Central California. Stationary Spray Plants in California. Yield, Stand, and Volume Tables for White Fir in the California Pine Region. Alternaria Rot of Lemons. The Digestibility of Certain Fruit By- products as Determined for Rumi- nants. Part I. Dried Orange Pulp and Raisin Pulp. Factors Influencing the Quality of Fresh Asparagus after it is Har- vested. Paradichlorobenzene as a Soil Fumi- gant. A Study of the Relative Value of Cer- tain Root Crops and Salmon Oil as Sources of Vitamin A for Poultry. Planting and Thinning Distances for Deciduous Fruit Trees. The Tractor on California Farms. Culture of the Oriental Persimmon in California. Poultry Feeding : Principles and Prac- tice. A Study of Various Rations for Fin- ishing Range Calves as Baby Beeves. Economic Aspects of the Cantaloupe Industry. Rice and Rice By-Products as Feeds for Fattening Swine. Beef Cattle Feeding Trials, 1921-24. Cost of Producing Almonds in Cali- fornia : a Progress Report. Apricots (Series on California Crops and Prices). The Relation of Rate of Maturity to Egg Production. Apple Growing in California. Apple Pollination Studies in Cali- fornia. The Value of Orange Pulp for l\lilk Production. The Relation of Maturity of Cali- fornia Plums to Shipping and Dessert Quality. Economic Status of the Grape Industry. Range Grasses of California. Raisin By-Products and Lean Screen- ings as Feeds for Fattening Lambs. Some Economic Problems Involved in the Pooling of Fruit. Power Requirements of Electrically Driven Manufacturing Equipment. No. 434. 435. 436. 437. 438 439. No. 87. 115. 117. 127. 129. 136. 144. 157. 164. 166. 173. 178. 179. 202. 203. 209. 212. 215. 217. 230. 231. 232. 234. 238. 239. 240. 241. 243. 244. 245. 248. 249. 250. 252. 253. 254. 255. BULLETINS- Investigations on the Use of Fruits in Ice Cream and Ices. The Problem of Securing Closer Relationship Between Agricultural Development and Irrigation Con- struction. I. The Kadota Fig. II. Kadota Fig Products. Economic Aspects of the Dairy In- dustry. Grafting Affinities with Special Refer- ence to Plums. The Digestibility of Certain Fruit By- products as Determined for Rumi- nants. Part II. Dried Pineapple Pulp, Dried Lemon Pulp, and Dried Olive Pulp. (Continued) No. 440. The Feeding Value of Raisins and Dairy By-Products for Growing and Fattening Swine. 441. The Electric Brooder. 442. Laboratory Tests of Orchard Heaters. 443. Standardization and Improvement of California Butter. 444. Series on California Crops and Prices: Beans. 445. Economic Aspects of the Apple In- dustry. CIRCULARS No. Alfalfa. Grafting Vinifera Vineyards. The selection and Cost of a Small Pumping Plant. House Fumigation. The control of Citrus Insects. Melilotus Indica as a Green-Manure Crop for California. Oidium or Powdery Mildew of the Vine. Control of Pear Scab. Small Fruit Culture in California. The County Farm Bureau. The Construction of the "Wood-Hoop Silo. The Packing of Apples in California. Factors of Importance in Producing Milk of Low Bacterial Count. County Organization for Rural Fire Control. Peat as a Manure Substitute. The Function of the Farm Bureau. Salvaging Rain-Damaged Prunes. Feeding Dairy Cows in California. Methods for Marketing Vegetables in California. Testing Milk, Cream, and Skim Milk for Butterfat. The Home Vineyard. Harvesting and Handling California Cherries for Eastern Shipment. Winter Injury to Young Walnut Trees During 1921-1922. The Apricot in California. Harvesting and Handling Apricots and Plums for Eastern Shipment. Harvesting and Handling California Pears for Eastern Shipment. Harvesting and Handling California Peaches for Eastern Shipment. Marmalade Juice and Jelly Juice from Citrus Fruits. Central Wire Bracing for Fruit Trees. Vine Pruning Systems. Some Common Errors in Vine Prun- ing and Their Remedies. Replacing Missing Vines. Measurement of Irrigation Water on the Farm. Support for Vines. Vineyard Plans. The Use of Artificial Light to In- crease Winter Egg Production. Leguminous Plants as Organic Fer- tilizers in California Agriculture. 257. 258. 259. 261. 264. 265. 266. 267. 269. 270. 273. 276. 277. 278. 279. 281. 282. 283. 284. 286. 287. 288. 289. 290. 292. 293. 294. 296. 298. 300. 301. 302. 304. 305. 306. 307. 308. 309. 310. 311. The Small-Seeded Horse Bean (Vicia faba var. minor). Thinning Deciduous Fruits. Pear By-Products. Sewing Grain Sacks. Preliminary Essentials to Bovine Tu- berculosis Control in California. Plant Disease and Pest Control. Analyzing the Citrus Orchard by Means of Simple Tree Records. The Tendency of Tractors to Rise in Front; Causes and Remedies. An Orchard Brush Burner. A Farm Septic Tank. Saving the Gophered Citrus Tree. Home Canning. Head, Cane and Cordon Pruning of Vines. Olive Pickling in Mediterranean Countries. The Preparation and Refining of Olive Oil in Southern Europe. The Results of a Survey to Deter- mine the Cost of Producing Beef in California. Prevention of Insect Attack on Stored Grain. Fertilizing Citrus Trees in California. The Almond in California. Milk Houses for California Dairies. Potato Production in California. Phylloxera Resistant Vineyards. Oak Fungus in Orchard Trees. The Tangier Pea. Alkali Soils. The Basis of Grape Standardization. Propagation of Deciduous Fruits. Control of the California Ground Squirrel. Possibilities and Limitations of Coop- erative Marketing. Coccidiosis of Chickens. Buckeye Poisoning of the Honey Bee. The Sugar Beet in California. Drainage on the Farm. Liming the Soil. A General Purpose Soil Auger and Its Use on the Farm. American Foulbrood and Its Control. Cantaloupe Production in California. Fruit Tree and Orchard Judging. The Operation of the Bacteriological Laboratory for Dairy Plants. The Improvement of Quality in Figs. The publications listed above may be had by addressing College of Agriculture, University of California, Berkeley, California. 8m-5,'28