LIERARY. » CAMPU3, / / ~—~ A A388-1127-6000-L180 TEXAS AGRICULTURAL EXPERIMENT STATIIIN B. YOUNGBLOOD, DIRECTOR COLLEGE STATION, BRAZOS coumw, TEXAS \ BULLETIN NO. 371 DECEMBER, 1927 ERIOULTITRAL a3 EEEGEANIGAL (XILEEEEEEPEJEEFPEEEKEESEEBRARY THE EEEECT OE SALT WATER ON RICE AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS T. O. WALTON, President STATION STAFFT ADMINISTRATION: *B. YOUNGBLOOD, M. S., Ph. D., Director . B. CoNNER, M. S., Acting Director . E. KARPER, B. S., Acting Vice-Director . M. SGHAEDEL, Secretary . P. HOLLEMAN, JR., Chief Clerk . K. FRANcKLow, Assistant Chief Clerk HESTER HIGGS, Executive Assistant . B.’ NFEIETTE, Technical Assistant EMISTRY: _ _ . S. FRAPs, Ph. D., Chief; State Chemist . C. CARLYLE, B. S.,. hemist . E. AsBURY, M. S., Assistant Chemist ALDO H. WALKER, Assistant Chemist ELMA GRAHAM, Assistant Chemist . O. BROOKE, M. S., Assistant Chemist . L. OGIER, B. S., Assistant Chemist . G. EvANs, Assistant Chemist _ ATHAN J. STERGES, B. S., Assistant Chemist G. S. CRENSHAW, A. B.,-Assistant Chemist JEANNE M. FUEcAs, Assistant Chemist HORTICULTURE: _ , Chief H. NEss, M. S., Berry Breeder ' RANGE ANIMAL I-IUSBANDRY: J. M. JoNEs, A. M., Chief; Sheep and Goat Investigations , J. L. LUSH, Ph. D.,_ Animal Husbandman; Breeding Investigations W. H. DAMERON, B. S., Wool Grader ENTOMOLOGY: F. L. THOMAS, Ph. D., Chief; State Entomologist _ . J. REINHARD, B. S., Entomologist . K. FLETCHER, M. A., Entomologist . L. OWEN, JR., NI. S., Entomologist RANK M. HULL, M. S., Entomologist . C. GAINEs, JR., M. S., Entomologist . J; ToDD, B. S., Entomologist . F. BIBBY, B. S., Entomologist _ ' . E. McGREGQR, JR., Acting Chief Foulbrood Inspector . B. KENNERLY, Foulbrood Inspector ILLIs GRAHAM, Foulbrood Inspector . B. REYNOLDs, M. S., Chief _ _ . B. CoNNER, M. S., Agronomist; Grain Sorghum Research . E. KARPER, B. S., Agronomist; Small Grain Research MANcELsDoRF, Sc. D., Agronomist; in charge of Corn and Small Grain Investi- gations _ T KILLoUc-II, M. S., Agronomist; Cotton Breeding . E. REA, B. S., Agronomist; Cotton Root Rot Investigations . C. CUsnING, B. S., Assistant in Crops R. JOHNSON, B. S., Assistant in Soils nn~g~w> C ~emm§m> o z o Z F SUBSTATIONS No. 1, Beeville, Bee County: A. HALL, B. S., Superintendent No. 2, Troup, Smith County: W. S. HoTcIiKIss, Superintendent No. 3, Angleton, Brazoria County: R. H. STANsEL, M. S., Superintendent FRANK M. HULL, M. S., Entomologist No. 4, Beaumont, Jefierson County: R. H. WYcIIE, B S., Superintendent No. 5, Temple, Bell County: HENRY DUNLAVY, M. S., Superintendent B. F. DANA, M. S., Plant Pathologist H. E. REA, B._S., Agronomist; Cotton Root Rot Investigations . No. 6, Denton, Denton County: P. B. DUNKLE, B. S., Superintendent No. 7, Spur, Dickens County: R. E. DICKSON, B. S., Superintendent No. 8, Lubbock, Lubbock County: D L. JoNEs, Superintendent FRANK GAINEs, Irrigationist and Forest Nurseryman . No. 9, Balmorhea, Reeves County: J. J. BAYLES, B. S., Superintendent Teachers in the School of Agriculture Carrying Cooperative Projects on the Station: - . ADRIANcE, M. S., Associate Professor of Horticulture G. W S. BILSING, Ph. D., Professor of Entomology V. . LEE, Ph. D., Professor of Marketing and Finance D. ScoATEs, A. E., Professor of Agricultural Engineering _ _ H. P. SMITH, M. S., Associate Professor of Agricultural Engineering **Dean, School of Veterinary Medicine. TAs of December 1, 1927. *On leav ****In coop e. _ _ ***In_ cooperation with U. eration with the School of Agriculture. VETERINARY SCIENCE: **M. FRANcIs. D. V. M., Chief I H. SCHMIDT, D. V. M., Veterinarian ’ J. D. JoNEs, D. V. M., Veterinarian - PLANT PATHOLOGY AND PHYSIOL = J. J. TAUBENHAUS, Ph. D., hi ' L. J. PEssIN, Ph. D., Plant Pathologist ‘ Laboratory Technician . - K -W. J. BACH, S., Plant Pathologist J. PAUL LUsK, S. M., Plant Pathologist B. F. DANA, M. S.. Plant Pathologist FARM AND RANCH ECONOMICS: L. P. GABBARD, M. S., Chief *B. YoUNGBLooD, M. S., Ph. D., Farm _ Ranch Economist , ' G. L. CRAWFORD, M. S., Marketing Res Specialist ,_ C. A. BoNNEN, M. S., Farm Managem' ; Research Specialist _ t” V. L. CORY, M. S., Grazing Research Bot ***T. L. GAsToN, JR., B S., Assistant; Records and Accounts 7. ***J. N. TATE, B. S., Assistant; Ranch R and Accounts l RURAL HOME RESEARCH: ‘ ~_: _ JEssIE WHITACRE, Ph. D., Chief ' MAMIE GRIMES, 1V1. S., Textile and Clo '_ Specialist fl SOIL SURVEY: ;, ***W. T. CARTER, B. S., Chief '- H. W. HAwKER, Soil Surveyor E. H. TEMPLIN, B. S., S_oil Surveyor :1» T. C. REITCH, B. S., Soil Surveyor BOTANY: i H. NEss, M. S., Chief ‘ ~- PUBLICATIONS: A. D. JACKSON, Chief SWINE HUSBANDRY: FRED HALE, M. S., Chief DAIRY HUSBANDRY: , Chief POULTRY HUSBANDRY: ' R. M. SHERWOOD, M. S., Chief ****AGRICULTURAL ENGINEERING: i} MAIN STATION FARM: I G. T. McNEss, Superintendent APICULTURE (San Antonio): H. B. PARKS, B. S., Chief A. H. ALEX, B. S., Queen Breeder FEED CONTROL SERVICE: " F. D. FULLER, M. S., Chief S. D. PEARcE, Secretary J. H. ROGERS, Feed Inspector W. H. W00D, Feed Inspector - x K. L. KIRKLAND, B. S., Feed Inspector s? W. D. NORTHCUTT, JR., B. S., Feed Ins SIDNEY D. REYNQLDS, JR., Feed Inspector, P. A. MoonE, Feed Inspector ‘f. No. 10, Feeding and Breeding Station, » College Station, Brazos County: . SHERWOOD, M. S., Animal H _ man in Charge of Farm L. J . McCALL, Farm Superintendent No. ll, Nacogdoches, Nacogdoches Conn H. F. MQRRIs, M. S., Superintendent ***No. 12, Chillicothe, Hardeman County . J. R. QUINBY, B. S., Superintendent ***J. C. STEPHENS, M. A., Junior Agro N0. 14, Sonora, Sutton-Edwards Counties E. W. THOMAS, B. S., Superintendent —————-—i——i-——-, Veterinarian V. L. CoRY, M. S., Grazing Research it ***O. G. BABCOCK, B. S., Collaborating Entomologist O. L. CARPENTER, Shepherd No. 15, Weslaco, Hidalgo County: ’ W. H. FRIEND, B. S., Superintendent‘ ———~.——-—————~, Entomologist _ W. J. BACH, M. S., Plant Pathologist No. 16, Iowa Park, Wichita County: E. J. WILsoN, B. S., Superintendent _ J . PAUL LUsK, S. M., Plant Pathologist V S. Department of Agri SYNOPSIS Rice farmers sometimes have trouble with salt in the water used for irrigation. Varying conditions, such as character of soil, amount of water already on the land, stage of growth of the rice, and others, render it diflicult to say how much salt in the water would be injurious. Advantage was taken of a dry season to study the amount 0f salt in water as related to the yields of the crops on which it was used. Data were also secured from some irrigation concerns. It is difficult to establish a limit to the amount of salt in the water to be used, but it is probably best to stop pumping when the water con- tains over 50 grains of salt to the gallon. However, water has been used containing 100 grains to the gallon with fair results, especially after August 1. A method for estimating salt in water is described. CONTENTS PAGE Introduction . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Previous Work . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Danger depends on conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 Results ofla pot experiment . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 Field study in J efierson County . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .. 6 Other observations in various sections . . . . . . . . . . . . . . . . . . . . . . . . .. 8 Method for the approximate estimation of salt in Water . . . . . . . . . . . 10 Summary and conclusion . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . , . . . . . 10 BULLETIN NO. 371 DECEMBER, 1927 THE EFFECT OF SALT WATER ON RICE G. S. FRAPS The occurrence of salt in Water used for irrigation is sometimes a difficulty in Texas. At some of the rice farms located near the gulf coast of Texas, the amount of Water pumped is sometimes greater than the capacity of the stream and as a result salt waterefinds its way up the stream and is pumped upon the fields. This is more liable to occur in dry than in moist seasons. Also, at times, salt water from the oil fields has found its way into streams used for irrigation. Salt water is known to have an injurious effect upon rice. The object of the Work here reported is to ascertain, if possible, what amount of salt water is dangerous. It i_s a continuation of work published in Bulletin 122 (June, 1909). ‘ PREVIOUS WORK Texas Bulletin 122 contains reports of pot experiments, and reaches the following conclusions: (1) Water containing 0.3 per cent salt or over (.175 grains per gallon) is dangerous to rice. Water containing less may be dangerous. (2) Water containing 0.5 per cent salt or over (292 grains per gallon) should not be used. (3) Water may be tested by taste, by a urinometer, or by silver nitrate. A method is outlined. The silver nitrate method will prob- ably be most satisfactory. . The Louisiana Experiment Station, in Bulletin 171 (1920), sum- marizes the results of some observations, pot tests and field tests, and comes to the following conclusions: (1) More than 35 grains per gallon of salt should not be used in a flooding of from 41 to 8 inches if this amount of salt water is to remain on the field until the water evaporates or is diluted with fresh water. (2) Flooding a second time with water containing more than 15 grains of salt per gallon is not advisable. (3) It may or may not be harmful to use water containing 50 grains of salt on land which is wet at the time of the application of the salt Water, if it is possible to remove all of the salt water and replace with fresh water within two weeks of the time that the salt water is applied. DANGER DEPENDS ON CONDITIONS The danger from salt water depends upon the degree of saltiness, the length of time it goes on the land, the stage of growth of the plant, the amount of rainfall, the permeability of the soils, and perhaps other conditions. The water pumped upon the fields is diluted by that already 6 BULLETIN NO. 371, TEXAS AGRICULTURAL EXPERIMENT STATION present, so that water containing comparatively large quantities of salt may be pumped for a short time and do little damage except near the point of inflow. Water containing a small percentage of salt may cause injury when pumped for some time, on account of the accumulation of the salt. RESULTS OF A POT EXPERIMENT Another pot experiment, in addition to those reported in Bulletin 122, was conducted in 1918. The pots were partly damaged by mice; so the results are only given in a general way. One addition of 0.2 per cent salt Water made two Weeks after planting, killed the plants of Honduras and Blue Rose, but did not kill those of a special Japan variety of rice supposed to be resistant to salt water, although the yield of the latter was only about one-third of that in the pot which received no salt water. One addition sufficient to make the water in the pot contain 0.2 per cent of salt, 5 weeks after planting, killed the Honduras and Japan but gave a good yield of rice on the check with the special Japan, but 0.3 per cent salt solution covered a yield of about one-third the check. One addition to make the water contain 0.2 per cent salt, seven weeks after planting, injured the Honduras and Japan to some extent but did not kill them, while it apparently did not injure the special Japan rice. v The Honduras variety of rice seemed to be less resistant than the Japan, while the Special Japan seemed to be most resistant to salt water. One irrigation to make the salt content of all the water 0.2 per cent (117 grains per gallon) caused decided injury with the first two varieties. ~ FIELD STUDY INK JEFFERSON COUNTY An unusually dry season and the presence of salt water in the irriga- tion canals gave opportunity in 1925 to study the relation between the water used and its effects on the rice. Samples of water were collected by Mr. R. H. Wyche, Superintendent, Texas Substation No. 4e, near Beaumont, and Mr. J. O. Eisentraut, County Agent of Jefferson County, and were subjected to analysis in this laboratory. Mr. Wyche and Mr. Eisentraut also collected data on the rice fields at the end of the season. The results of the analysis and the yields of rice are given in Table 1. Discussion of Results Apparently the irrigation water and the water in the fields may contain 5O grains of salt per gallon up to August 1, and yet profitable yields be produced. 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I 8 BULLETIN NO. 371, TEXAS AGRICULTURAL EXPERIMENT STATION OTHER OBSERVATIONS IN VARIOUS SECTIONS The following are some additional observations. One rice man wrote some years ago as follows: “We have made a season here on salt water exclusively with over 12,000 acres. Our results are largely in line with yours as outlined briefly in Bulletin 122. One noticeable result has been the absence of pollen at the flowering stage, resulting in, of course, no fruit. Another peculiarity reported by farmers is a second crop of heads which fill and mature so that we will get probably over a half crop of Honduras. “This would indicate a subsequent adjustment of the plant to the abnormal condition. “It is very difficult for us to draw any reliable conclusion for the reason that with about 70 farmers as observers and no two working under exactly the same conditions We get all sorts of results reported. Our water has varied in quality almost hourly at times and after making allowance for temperature would contain from .05 per cent to .4 per cent ‘with an average estimated .2 per cent salt. “We carried our crops in the finest condition up to the fruiting period. The foliage of the plants gave promise of a full crop but the salt seemed to prevent the development of the pollen in very many cases, resulting in chaffy heads with no grain. “Some plants show resistant characters, while others under the same conditions fail utterly. It would be a fine opportunity to develop a salt-resistant strain if anybody had any use for that sort of rice. “I am inclined to think that one irrigation of .05 per cent water would be beneficial but wouldn’t want any more of a good thing of that kind.” Another writes as follows: “The water now in the stream contains about 70 grains (.12 per cent) per gallon and the farmers are afraid to use it on their young rice. The upper portions of the streams Show less salt water, running from 25 to 30 grains (.0510 per cent) per gallon and where it shows no larger percentage than this the planters are all using the water for irrigation with very good results. However, as you know, the efiects of the saltion the rice do not make their appear- ance until about the time the rice is heading out. In other words a little salt in the water seems to make the straw grow fine, but the heads are blighted.” . ANALYSIS OF WATER PUMPED ON RICE COMPARED WITH YIELD Tables 2 and 3 show the estimation of salt in water made by one of the irrigation companies in the State; The average yield of rice on the fields watered by this company in 1917 was 11.1 sacks; in 1918, 7.5 sacks; in 1919, 6.4 sacks; and in 1920, 4.8 sacks. Although there was more salt in the water in 1918, and a lower yield of rice, yet the yield was better than in 1919 and 1920 when there was no trouble from salt water. THE EFFECT OF SALT WATER ON RICE 9 Table 2.-——Salt in water pumped (grains per gallon). Average yield per acre 11.16 sacks. Date Grains Date Grains Date Grains l\/Iay 12 . . . . . . . . . . . 5O July 13 . . . . . . . . . . . 30 Aug. 15 . . . . . . . . . . . 30 May 14 . . . . . . . . . .. 110 July 15 . . . . . . . . . .. 30 Aug. 16 . . . . . . . . . .. 32 May 15 . . . . . . . . . .. 95 July 17 . . . . . . . . . .. 35 Aug. 17 . . . . . . . . . .. 4s May 16 . . . . . . . . . .. 45 July 1s . . . . . . . . . .. 40 Aug. 18 . . . . . . . . . .. 5o May 17 . . . . . . . . . .. 75 July 19 . . . . . . . . . .. 44 Aug. 19 . . . . . . . . . .. 62 May 19 . . . . . . . . . . . 85 July 20 . . . . . . . . . . . 36 Aug. 2O . . . . . . . . . . . 74 May 20 . . . . . . . . . . . 100 July 22 . . . . . . . . . . . 35 Aug. 21 . . . . . . . . . . . 86 May 21 . . . . . . . . . . . 75 July 23 . . . . . . . . . . . 38 Aug. 22 . . . . . . . . . . . 90 May 22 . . . . . . . . . . . 60 July 24 . . . . . . . . . . . 70 Aug. 24 . . . . . . . . . . . 90 May 23 . . . . . . . . . .. 45 July 25 . . . . . . . . . .. 45 Aug. 25 . . . . . . . . . .. s2 May 24 . . . . . . . . . .. 3s July 25 . . . . . . . . . .. 3s Aug. 2s . . . . . . . . . .. 95 May 25 . . . . . . . . . . . 22% July 27 . . . . . . . . . . . 28 Aug. 27 . . . . . . . . . . . 85 May 26 . . . . . . . . . . . 15 July 28 . . . . . . . . . . . 25 Aug. 28 . . . . . . . . . . . 65 May 27 . . . . . . . . . . . 12% July 31 . . . . . . . . . . . 27 Aug. 30 . . . . . . . . . . . 62 May 28 . . . . . . . . . . . 12% Aug. 1 . . . . . . . . . . . 27 Aug. 31 . . . . . . . . . . . 54 May 29 . . . . . . . . . . . 12% Aug. 4 . . . . . . . . . . . 25 Sept. 1 . . . . . . . . . . . 52 May 31' . . . . . . . . . . . 1O Aug. 5 . . . . . . . . . . . 25 Sept. 2 . . . . . . . . . . . 52 June 1 . . . . . . . . . .. 10 Aug. 6 . . . . . . . . . .. 20 Sept. 3 . . . . . . . . . .. 54 June 2 . . . . . . . . . .. 6 Aug. 9 . . . . . . . . . .. 22 Sept. 4 . . . . . . . . . .. 60 June 4 . . . . . . . . . . . 7% Aug. 1O . . . . . . . . . . . 22 Sept. 5 . . . . . . . . . . . 60 July 2 . . . . . . . . . .. 17% Aug. 11 . . . . . . . . . . . 14 Sept. 6 . . . . . . . . . .. 67 July 3 . . . . . . . . . . . 22 Aug. 12 . . . . . . . . . . . 13 Sept. 7 . . . . . . . . . . . 64 July 4 . . . . . . . . . .. 30 Aug. 14 . . . . . . . . . .. 20 Sept. 8 . . . . . . . . . .. ' 56 Table 3.—Salt in Water pumped, 1918 (grains per gallon). Average yield per acre 7.53 sacks. Date Grains Date Grains Date Grains May 2O . . . . . . . . . . . 13 July 28 . . . . . . . . . . . 120 Aug. 12 . . . . . . . . . . . 185 July 11 . . . . . . . . . .. 20 July 29 . . . . . . . . . .. 115 » Aug. 13 . . . . . . . . . .. 175 July 12 . . . . . . . . . . . 30‘ July 30 . . . . . . . . . .. 125 Aug. 14 . . . . . . . . . . . 155 July 13 . . . . . . . . . . . 4O July 31 . . . . . . . . . .. 135 Aug. 15 . . . . . . . . . . . 105 July 14 . . . . . . . . . . . 5O Aug. 2 . . . . . . . . . . . 130 Aug. 16 . . . . . . . . . . . 105 July 16 . . . . . . . . . . . 75 Aug. 3 . . . . . . . . . . . 155 Aug. 20 . . . . . . . . . . . 100 July 17 . . . . . . . . . . . 87 Aug. 4 . . . . . . . . . . . 165 Aug. 21 . . . . . . . . . . . 145 July 18 . . . . . . . . . . . 100 Aug. 5 . . . . . . . . . . . 175 Aug. 22 . . . . . . . . . . . 150 July 18 . . . . . . . . . . . 115 Aug. 6 . . . . . . . . . . . 205 Aug. 23 . . . . . . . . . . . 145 July 21 . . . . . . . . . . . 110 Aug. 7 . . . . . . . . . . . 225 Aug. 24 . . . . . . . . . . . 105 July 24 . . . . . . . . . . . 125 Aug. 8 . . . . . . . . . . . 215 Aug. 25 . . . . . . . . . . . 95 July 25 . . . . . . . . . . . 125 Aug. 9 . . . . . . . . . . . 225 Aug. 27 . . . . . . . . . . . 95 July 26 . . . . . . . . . . . 130 Aug. 10 . . . . . . . . . .. 225 Sept. 1 . . . . . . . . . .. 70 July 27 . . . . . . . . . .. 115 Aug. 11 . . . . . 200 The irrigation company made the following remarks 0n this point: “The yield of rice has been much greater during the dry years, even though the water contains considerable salt at times; this is particularly true where the dry weather occurs during the planting season so the farmers can get their lands in a state of thorough cultivationa In other words, during wet winters and springs, the ground seems to‘ be more or less soggy and sour and the rice does not grow and produce as well as when we have dry winters and springs. This is proven not only in Texas, but in California as well. . “The years 1918, 1920, 1921 and 1922 were years when there was either an excess of moisture during the winters and springs or a wet fall, which accounts for the low yields during those years. Therefore, with- out knowing the conditions in each instance, it is hard to arrive at the damage that the rice people sustain on account of the salt content of the water. 10 BULLETIN NO. 371, TEXAS AGRICULTURAL EXPERIMENT STATION “We have several farms covering large acreages that Were an absolute failure 0n account of the use of salt water in 1925. On other farms Where the yield of rice has been reduced fully 5O per cent, the salt con- tent was excessive during the irrigation period, and in still other in- stances, the application of salt Water (containing as much as 150 grains of salt) placed on young rice, and later irrigated throughout the year with fresh water, resulted in not more than 50 per cent of a normal crop, and in adjoining fields where nearly as much salt was used on a different variety of rice, the yield was better than normal.” METHOD FOR THE APPROXIMATE ESTIMATION OF SALT IN WATER A method for the estimation of salt in water is described below and should give satisfactory results. The Work could be checked by a chem- ical laboratory, by testing a sample of Water by this method, and sending a portion of the same sample to a laboratory for testing. A glass- stoppered burette is recommended for measuring the silver nitrate. Solutions. Tenth normal silver nitrate O1- 3 gglutign of 8_5() grams fused silver nitrate in 500 cc. distilled water. This solution must be protected from the light. Pfltassillm chrimlate- One gram in 100 cc. distilled Water. Apllaratlls- A 100 cc. graduated cylinder, and a 12 oz. bottle. More accurate results are secured with a burette. Methvd- Rinse the bottle and cylinder with distilled water or good cistern water. Measure 9O cc. of the water to be tested into the bottle. Add a few drops of the potassium chromate solution, so that the water is colored slightly yellow. Put 40 cc. silver nitrate in the cylinder and add it slowly to the water in the bottle until the color changes to a brick red. Multiply the number of cubic centimeters of silver nitrate used by 3. The result is the grains of salt to the gallon. SUMMARY AND CONCLUSIONS (1) Salt sometimes occurs in irrigation water used for rice, at times causes injury. » (2) The damage caused by salt water depends on several conditions, such as the amount of salt in the water, the length of time it is allowed to flow on the land, the amount of rainfall, the variety of rice grown and other conditions. \ (3) A study was made of the salt content and yield of rice during an unusually dry season. Data were also secured from some of the irrigation concerns. (4) It is ditficult to establish a limit to the amount of salt in the water to be used, but it is probably safer to be conservative and stop pumping when the water contains 40 to 50 grains of salt to the gallon. However, data are given which show that water containing much more than this has been used with fair yields, especially after August 1. (5) A method for estimating salt in water is described.