lizéils AGRICULTURAL EXPERIMENT smum AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS W. B. BIZZELL, President SEPTEMBER, 192-1 BULLETIN NO. 325 DIVISION OF CHEMISTRY EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL "‘" f: ,. IQ". I") 1| . | will; .|~. l == ‘r___ f '11‘: 1""? v I In‘: . WEE» ~ I 1114'?‘ El; Jlfflfiiill", IIIEEEEIE! 4 EEEEETEEEI.ET» I I I B. YOUNGBLOOD, DIRECTOR COLLEGE STATION, BRAZOS CO_UNTY, TEXAS ADMINISTRATION B. YOUNGBLOOD, M. S., Ph. D., Director A. B. CONNER, M. S., Vice Director A. H. LEIDIGH, M. S., Assistant Director CHAS. A. FELKER, Chief Clerk A. S. WARE, Secretary M. P. HOLLEMAN, JR., Assistant Chief Clerk J. M. SCHAEDEL, Executive Assistant VETERINARY SCIENCE *M. FRANCIS, D. V. M., Chief of Division H. SCHMIDT, D. V. M., Acting for Chief of Division VI J. BRAUNER, D. V. M., Veterinarian CHEMISTRY G. S. FRAPS, Ph. D., Chief of Division; State Chemist S. E. ASBURY, M. S., Assistant Chemist WALDO H. WALKER, Assistant Chemist J. K. BLUM, B. S., Assistant Chemist J. E. TEAGUE, B. S., Assistant Chemist VELMA GRAHAM, Assistant Chemist H. STANFORD, B. S., Assistant Chemist K. KITSUTA, M. S., Assistant Chemist ADAH E. PROCTOR, B. S., Assistant Chemist HORTICULTURE ' A. T. POTTS, M. S., M. S. C., Chief of Division," Citriculturist H. NESS, M. S., Berry Breeder RANGE ANIMAL HUSBANDRY J. M. JONES, A. M., Chief of Division; Sheep and Goats JAY L. LUSH, Ph. D., Animal Breeder (genetics) . J. J. HUNT, Wool Grader ENTOMOLOGY F. L. THOMAS, Ph. D., Chief of Division; State Entomologist "H. J. REINHARD, B. S., Entomologist E. HOBBS, B. S., Assistant Entomologist C. S. RUDE, Ii. S., Chief Foul Brood Inspector ’ W. R. JORDAN, B. S., Apiary Inspector AGRONOMY E. B. REYNOLDS, M. S., Chief of Division A. B. CONNER, M. S., Agronomist, Grain Sorghum Research A. H. LEIDIGH, M. S., Agronomist, Small Grain Research STAFF (As of October 1, 1924) G. .N. STROMAN, Ph. D., Agronomist, Cotton Breeding C. H. MAHONEY, B. S., Assistant in Cotton Breeding R. H. STANSEL, B. S., Assistant in Crops PLANT PATHOLOGY AND PHYSIOLOGY J. J. TAUBENHAUS, Ph. D., Chief o Division ' FARM AND RANCH ECONOMICS L. P. GABBARD, M. S., Chief of Division B. YOUNGBLOOD, M. S., Ph. D., Farr: and Ranch Economist V. L. CORY, M. S., Grazing Research Botanist (Sonora) ***T. L. GASTON, JR., B. S., Assistant, Farn * Records and Accounts ***A. S. BRIENT, B. S., Assistant, Ranch Records and Accounts SOIL SURVEY ***W. T. CARTER, ‘B. S., Chief of Division H. W. HAWKER, Soil Surveyor E. H. TEMPLIN, B. S., Soil Surveyor BOTANY H. NESS, M. S., Chief of Division PUBLICATIONS A. D. JACKSON, Chief of Division C. M. MITCHELL, Mailing Clerk SWINE HUSBANDRY G. R. WARREN, M. S., Chief of Division DAIRY HUSBANDRY G. R. WARREN, M. S., Chief of Division POULTRY HUSBANDRY . R. M. SHERWOOD, M. S., Chief of Divisim MAIN STATION FARM D. T. KILLOUGH, B. S., Superintendent STATE APICULTURAL RESEARCH LABORATORY (San Antonio) H. B. PARKS, B. S., Apiculturist in Charg< ‘A. H. ALEX, B. S., Queen Breeder FEED CONTROL SERVICE . F. D. FULLER, M. S., Chief of Division S. D. PEARCE, Secretary J. H. ROGERS, Feed Inspector W. H. WOOD, Feed Inspector J. F. SCHULTZ, B. S., Feed Inspector C. M. MORRIS, B. S., Feed Inspector F. W. WILSON, B. S., Feed Inspector W- C- GAINEY, B- 5» Feed Inspector SUIZSTATIONS No. l, Beeville, Bee County . A. HALL, B. S., Superintendent No. 2, Troup, Smith County W. S. HOTCHKISS, Superintendent No. 3, Angelton. Brazoria County V. E. HAFNER, B. S., Superintendent No. 4, Beaumont, Jefferson County R. H. WYCHE, B. S., Superintendent No. 5, Temple, Bell County A. B. CRON, B. S., Superintendent 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 Coounty R. E. KARPER, B. S., Superintendent No. 9. Balmorhea, Reeves County J. J. BAYLES, B. S., Superintendent No. I0, College Station, Brazos (Feeding and Breeding substation) County E. J. \VILSON B. N0- 11, NHCOQQIoches, Nacogdoches County G T. McNEaS, Superintendent ***No. 12. Chillicothe, Hardeman County D. L. JONES, Superintendent No. 14, Senora. Sutton-Edwards Counties E. M. PETERS, B. S., Superintendent D. H. BENNETT, D. V. M., Veterinarian V- L- CORY. M. S., Grazing Researr-h Rntanis! ***O. G. BABCOCK, B. S., Collaborating En- tomofogist O. L. CARPENTER, Shepherd No. 15. Llano, Grande, Hidalgo County W. H. FRIEND, B. S., Superintendent A. T._ POTTS, M. S., M. S. C., Citrivul- turist No. 16, Iowa Park, Wichita County S., Superintendent G. R. WARREN, M. S., Animal Husband- man in Charge of Farm L. J. McCALL, Farm Superintendent Members of Teaching Staff in the School of Agriculture Carrying Cooperative Prcjecs: S. W. BILSING, Ph. D., Professor of Ento- mology W. L. STANGEL, M. S., Professor of Ani- mal Husbandry (Swine) F. A. BUECHEL, Ph. D., Professor of Agri- cultural Economics G. W. ADRIANCE, M. S., Associate Pro- fessor of Horticulture ‘Dean, School of Veterinary Medicine. "On leave for one year W. E. GARNETT, Ph. D., Rural Sociology G. P. GROUT, M. Husbandry R. C. WHITE, M. A., Associate Professor of Rural Sociology H- V- GEIB, B. S., Assistant Professor of Agronomy E. O. POLLOCK, A. M., Assistant Professor of Agronomy Professor of 5-, Professor of Dairy "fin cooperation with United States Department of Agriculture. SUMMARY The active potash, which is the potash dissolved by N /5 nitric acid, is decreased when crops are grown upon the soil. The soils studied were cropped in pot experiments, with additions of dicalcium phosphate and ammonium ni- trate. The amount of active potash lost from the soil in 409 experiments averages 40.9 per cent. of the potash re- moved by the crops. As successive extractions of the soil with the solvent remove active potash, and the soil also has a fixing power for potash, the active potash lost by cropping must be less than the potash removed by cropping. The correlation factor between the potash removed by the crops and the active potash lost from the soil is .722 t .016. This is a high correlation, Bulletin No. s25. i September, 1924 THE EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL G. S. Fraps In Bulletin 145 of this Station, it is shown that the potash removed by crops from pot experiments is related to the active potash of the soil. It was also shown that the effect of the cropping was to decrease the amount of active potash left in the soil. The object of the present Bulletin is to study the effect of cropping upon the active potash of the soil, SIGNIFICANCE OF ACTIVE POTASH The term active potash is applied to the potash dissolved from the soil by fifth-normal nitric acid. This method is founded upon the work of Dyer, and was developed through the work of various referees of the As- sociation of Official Agricultural Chemists. The amount of active potash l . . . 5 Par-fa fir MM/wn \ a A E \ x 80v Q . _ 3 \ 70 ' \ E I n \ \ _ \ 6.00 v ,,,. Bias/r //7 (r1512; . ‘ g \ i Qecrease Acf/‘ve Pafasb Q q s \ \ \ \ \ q i \ 5 z \ z \ 5 w \ z *4 \ o0 \ 4 \ \ I \ z E z z z 3 z x l E g z 3 E ~ ~ E z 200 i S Q : N \ E s /§ & Figure 1.—Re1ation between the potash lost by crops and the decrease in active potash of the soil. 6 BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION extracted from the soil depends upon the solubility of thelsoil potash in the solvent, and the fixing power of the soil under the conditions of the extraction (See Fraps Principles Agricultural Chemistry, page 183). All soils have a fixing power for potash, even in acid solutions, so that the amount of potash actually found does not represent the entire amount soluble in the solvent. A study of the solubility of the minerals containing potash in fifth- normal nitric acid shows that some of them, such as felspar, are very slightly soluble in the solvent, and others such as biotite, moderately soluble, and others completely soluble in the solvent. A study of the ef- fect of successive extractions upon the soil shows that unless the amount is very small the quantity of potash extracted becomes lower with each suc- cessive extraction, until it remains constant. The potash extracted by fifth-normal nitric acid thus comes in part from easily soluble potash compounds, and in part from highly insoluble potash compounds. The potash in the first extractions comes largely from easily soluble compounds, and after these are decomposed and their potash re- moved, the potash comes from the slightly soluble potash compounds. With any soil, there would finally come a time when uniform quantities of potash would be given up to successive extractions with the solvent. These extracts would contain potash from the difficultly soluble minerals, and the quantity extracted would depend upon the nature of the minerals, and the amount present. RELATION OF ACTIVE POTASH TO PLANT GROWTH It is clear from the preceding discussion that the active potash can- not have the same relation to plant growth on all soils. The potash taken up by plants must come in part from highly soluble potash compounds, and in part, although it may be small, from the slightly soluble potash com- pounds. It is plain that the significance of the active potash may be dif- ferent in soils of different origin containing potash minerals widely dif- ferent in character and relative quantity. - In Bulletin 190 of this Station, it was shown that carbonate of lime, carbonate of magnesia, and also the organic matter, affects to some extent the potash removed from the soil by crops, but there was no evidence that the lime releases so-called fixed potash. The active potash did not need anything to release it. It was easily taken up without the lime. In Bulletin 284 of this Experiment Station, it was shown that highly in- soluble potash minerals give up some of their potash to plants in pot experiments, but minerals containing the potash in forms more easily sol- uble in acids give up- their potash more readily to plants and that there is a relation between the solubility in the weak acids of the potash of the min- eral and the amount of potash given up to plants in the pot experiments. The extraction of potash from the soil by plants is a biological action, and other factors are of influence in addition to the solubility of the soil potash. The kind of plant, the temperature at which the plant is grown, the amount of air in the soil, the physical condition of the soil, the or- EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL 7 ganic matter in the soil, the carbonate of lime in the soil, the hydrogen ion concentration of the soil and other conditions, no doubt influence the amount of potash withdrawn. It is quite possible that the amount of potash is so influenced by soil temperature that the potash removed by crops in Texas would not be the same as in cooler localities, such as Maine or Pennsylvania. This matter requires investigation. Consideration of the effect of successive extractions upon the soil shows that we cannot expect the active potash to decrease in quantity equal to that removed by the crop. The amounts of potash removed by successive extractions from some soils were as given in Table 1. i TABLE 1—Potash removed by successive extractions, in parts per million. Decrease Laboratory Extrac- Extrac- Extrac- Extrac- Extrac- Dlhlifzfgise - 9f iecong No. tion 1 tion 2 tion 3 tion 4 tion 5 First to ‘étiao , sews S18 24s 76 47 50 46 i 172 69.3 1122 167 75 45 59 92 92 55.1 2303 1066 1060 35 102 136 6 0.6 2301 94 57 30 45 66 37 39.4 2420 137 72 40 66 25 65 47.4 Supposing, for the sake of discussion, that crops should.remove all the potash represented by the first extraction, and the cropped soil was then subjected to extraction. We could expect the amounts of potash given up by the cropped soil to be those represented by the second extrac- tion. But the difference between the first extraction and the second extrac- tion is less than the potash removed by the crops or by the first extrac- tion. It varies from 0.6 to 69.3 per cent. in these particular soils. Hence we could expect the decrease of active potash in the cropped soil to be only part of the potash removed. Indeed, in the case of Soil 2303, the crops could remove part of the potash without affecting the active potash at all. METHOD OF WORK The method of work is the same as that previously described for pot experiments. The plants were grown in pots containing 5,000 grams of soil, which had been air-dried and pulverized. Phosphoric acid in the form of dicalcium phosphate, and nitrogen in the form of ammonium nitrate, were added to the pots to be studied for potash, and a pot to which sul- phate of potash was also added was always used in the series as a check. Corn and sorghum were grown in succession. Nitrogen and potash were always added to the second crop of. sorghum. If more than two crops were grown, the third crop always received another addition of phosphoric acid, nitrogen, or potash, corresponding to the previous application. The plants were grown in the greenhouse, and harvested at the end of about sixty days. The temperature in our greenhouse is quite high. Chemical analysis was always made of the crops which did not receive potash, for the amount of potash in these crops may vary to a wide extent. After the final harvest, 8 BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION the soil was allowed to dry, it was then sifted, the roots removed, and active potash estimated in it. When two pots were used, both without potash, they were treated as if different soils for the purpose of this work. TABLE 2—Effect of Cropping on Active Potash lost from the Soil, in parts per million. '5 i: i; .5 w w ° >. ' vq In Q8 "U GROUPS POTASH REMOVED A: g 5' 393w 953-8: c g; g m o *" w > 6 > q; w? u: .9 S o! 38° 83w 1:12:85? 5W3 £553 82s 25158.26 §~a2_ Group 0- 50 . . . . . . . . . . . . . . . . . . . . . 39 17 43.6 19 Group 51- 100 . . . . . . . . . . . . . . . . . . . . . 78 30 38.4 59 Group 101- 200 . . . . . . . . . . . . . . . . . . . . . 148 61 41.2 153 Group 201- 300 . . . . . . . . . . . . . . . . . . . . . 242 100 41.3 77 Group 301- 400 . . . . . . . . . . . . . . . . . . . .. 348 153 43.7 39 Group 401- 500 . . . . . . . . . . . . . . . . . . . . . 451 199 44.1 20 Group 501- 600 . . . . . . . . . . . . . . . . . . . . . 552 212 38.4 18 Group 601- 700 . . . . . . . . . . . . . . . . . . . . . 641 195 30.4 15 Group 701- 800 . . . . . . . . . . . . . . . . . . . . . 741 201 27.1 3 Group 801- 900 . . . . . . . . . . . . . . . . . . . . . 882 577 65.4 3 Group 901-1000 . . . . . . . . . . . . . . . . . . . .. 964 338 35.0 3 Total number of soils 409 RELATION OF THE POTASH REMOVED TO THE POTASH TAKEN UP BY THE CROPS Table 2 shows the average relation between the active potash lost from the soil, and the potash taken up by the crops. It is seen from the table that the amount of potash withdrawn from the soil increases with the active potash present. The average active potash lost by the cropping in per cent of the potash removed by the crop varies from 27.1 to 65.4 per cent. in the different groups, but is really remarkably constant at around 40 per cent. The relations are also shown in Figure 1. Details of the ex- periments are given in Table 4. THE CORRELATION BETWEEN THE ACTIVE POTASH REMOVED FROM THE SOIL AND THE ACTIVE POTASH LOST IN CROPPING The correlation between the potash removed from the soil by the crops. and the active potash lost from the soil, is shown as Table 3. The highest figures of the group are given. Thus the 25 group includes 0-25, the 50 group includes 25.1-50, and so on. Careful observation of this table shows that the relation is not the same in all cases, and that there is a consider- able variation in the loss of active potash from soils giving up the same- amount of active potash to crops. Differences in the character of minerals which furnish the active potash, and differences in the soil conditions, may partly account for this variation, as well as biological relations. The fact that the same number of crops was not grown in each case is no doubt ot’ influence, for since part of the active potash was removed by the first crop, the succeeding crops would have less active potash at their disposal, 9 e355 E032.» 3 owowm 8 3 .8 H0O Hum H0O H; MOO ~§ wmo w; woo Sm m8 3m 8o 5m .50 3m 8o Sm 8o w; moo 0mm 28 3m 400 <8 :8 3m .000 wmo H000 so?» EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL was midi son: é Mm 3 H0O Hum Hmo 5m woo N3 a8 3m v.8 3m £6 5o 5w 8o mum So Em 3o w? . 3o 3m b3 mHH Ho H» m < # h H m m H» H0 Hm Hm UL m HO m H» » w HM u N H u H 01001401 PmGubbl UI $079M Nblnhml-J FNNNi-‘I-‘NH D-"l-‘l-‘F-‘H N PblNl-‘l-‘N H (flbll-‘f-‘N b! l-‘D-‘P-‘D-J d. .3 2. 3 mo NOOOPOOHOHHOl-Jwmhr-ll-Imm uonwH wwmwqwu uu 8 mo i. 8 w» Z S m. Hm 5:‘ TABLE 8—-Correlation between the potash removed by crop and the active potash lost. 1f) BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION and would take a larger proportion of their potash from the difficultly soluble potash minerals. The co-efficient of correlation (r) between the potash removed by the crops and the active potash lost from the soil, calculated from Table 3, is .722 i .016. ' This is a high correlation and shows a high relation between the pct-_ ash removed by crops and the ‘active potash lost by soils. The correlation between the butter production of cows and of their daughters is 0.28, and between the height of men and their sons is 0.51 (Warren, N. Y. Bull. 416). There is thus much closer relation between the potash removed by crops and the active potash lost by the soil than there is between the butter-fat productions of cows and of their daughters, The regression coefficient is 0.409, which means that, on an average,‘ 40.9 per cent. of the potash removed by the crops is-taken from the active potash of the soil. This may be compared with the active potash lost by the first extractions in Table 1, which varies from 0.6 to 69.3 per c,ent., with an average of about 40. * DISCUSSION OF RESULTS The relation between the active potash of the soil and the results of pot experiments is emphasized by the relation between the potash removed from the soil by crops, and the loss of active potash from the soil. If the effect of cropping the soil is to withdraw some of the active potash from the soil, then the estimation of active potash in the soil must be of con- siderable significance. The determination of active potash is a useful method for examination of the soil, if properly used. When this method is applied to field conditions, other, factors make the problem more difficult. The depth of the surface soil, the depth of soil occupied by the roots of plants, the power of the plant to take up potash, the soil temperature, moisture conditions, variations in the chem- ical composition of the soil, and other factors, affect the relation of the active potash to the crops actually produced. This is evident in the wide variation found to occur in the production of crops grown upon the same field in good seasons, and in bad seasons. For example, wheat yielded 16 bushels in a wet season, and 35.7 bushels on an average,'at Rothamsted, on the plot receiving farm manure. ACKNOWLEDGEMENT Laboratory and other work involved in this Bulletin have been taken part in by S. E. Asbury, S. Lomanitz, John B. Smith, Waldo Walker, Velma Graham, and other members of the staff. EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL 11 TABLE 4—Details of experiments, in parts per million of active potash. In No. of Per L Lflb°mt°rY N°- Crops Crops Crop Before After °s5 Cropping Cropping 828 . . . . . . . . . . . . . . .. 45 1 45 111 75 36 859 . . . . . . . . . . . . . .. 21 1 21 40 36 4 860 . . . . . . . . . . . . . .. 48 2 24 71 78 0 1200 . . . . . . . . . . . . . .. 34 2 17 70 78 0 8843 . . . . . . . . . . . . . .. 32 2 16 60 37 23 9163 . . . . . . . . . . . . . .. 40 2 20 35 39 0 9163 . . . . . . . . . . . . . .. 21 2 11 35 29 6 9165 . . . . . . . . . . . . . .. 42 2 21 38 28 10 9165 . . . . . . . . . . . . . .. 31 2 16 38 34 4 9180 . . . . . . . . . . . . . .. 44 2 22 62 82 0 9281 . . . . . . . . . . . . . .. 49 2 25 70 41 29 9303 . . . . . . . . . . . . . .. 50 2 25 59 38 21 9303 . . . . . . . . . . . . . .. 34 2 17 59 39 20 9310 . . . . . . . . . . . . . .. 48 4 12 75 41 34 9329 . . . . . . . . . . . . . .. 44 2 22 63 36 27 9348 . . . . . . . . . . . . . ..I 30 I 2 I 15 71 94 0 9377 . . . . . . . . . . . . . .1 37 2 19 I 138 110 28 9384 . . . . . . . . . . . . . .J 47 2 24 76 67 9 Average group 0-50 . . 39 20 67 17 348 . . . . . . . . . . . . . .. 95 2 48 133 65 68 969 . . . . . . . . . . . . . .. 79 2 40 85 64 21 1129 . . . . . . . . . . . . . .. 61 2 31 75 60 15 1130 . . . . . . . . . . . . . .. 97 2 49 79 56 23 1586 . . . . . . . . . . . . . .. 52 2 26 55 41 14 1591 . . . . . . . . . . . . . .. 76 4 19 62 43 19 1592 . . . . . . . . . . . . . .. 71 5 14 87 59 28 1933 . . . . . . . . . . . . . .. 98 1 98 190 135 00 1956 . . . . . . . . . . . . . .. 80 2 40 105 68 37 2350 . . . . . . . . . . . . . .. 93 3 31 86 63 23 2351 . . . . . . . . . . . . . .. 74 1 74 92 101 0 2824 . . . . . . . . . . . . . .. 94 2 47 105 71 34 5099 . . . . . . . . . . . . . .. 60 2 30 84 59 25 8838 . . . . . . . . . . . . . .. 62 2 31 59 40 19 8839 . . . . . . . . . . . . . .. 75 2 38 45 45 0 8839 . . . . . . . . . . . . . .. 56 2 28 45 66 0 8843 . . . . . . . . . . . . . . . 55 2 28 60 28 32 9040 . . . . . . . . . . . . . .. 85 2 48 96 47 49 9041 . . . . . . . . . . . . . .. 75 4 19 91 45 46 9139 . . . . . . . . . . . . . .. 61 2 31 62 37 25 9139 . . . . . . . . . . . . . .. ' 70 2 35 62 28 34 9180 . . . . . . . . . . . . . .. 76 2 38 62 56 6 9273 . . . . . . . . . . . . . .. 89 4 22 113 83 30 9274 . . . . . . . . . . . . . . . 55 2 28 128 123 5 9274 . . . . . . . . . . . . . .. 56 2 28 128 113 15 9280 . . . . . . . . . . . . . .. 86 2 43 70 35 35 9280 . . . . . . . . . . . . . .. 66 2 33 70 38 2 9281 . . . . . . . . . . . . . .. 63 2 32 70 51 19 9306 . . . . . . . . . . . . . . . 61 4 15 42 42 0 9308 . . . . . . . . . . . . . .. 79 2 40 175 173 2 9309 . . . . . . . . . . . . . .. 76 4 19 91 49 42 9329 . . . . . . . . . . . . . .. 61 2 31 63 39 24 9336 . . . . . . . . . . . . . .. 99 4 25 87 77 10 9347 . . . . . . . . . . . . . .. 74 2 37 73 64 Q 9347 . . . . . . . . . . . . . .. 61 2 31 73 66 7 12 BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION Table 4 (Con.) Details of experiments, in parts per million of active potash. In ‘ No of Per Active Potash Laboratory No. Crops l Cr6ps Crop ifofig L°53 _ I Cropping Cropping 9348 . . . . . . . . . . . . . .. 76 ‘ 2 38 71 62 9 9349 . . . . . . . . . . . . . .. 100 4 25 104 60 44 9354 . . . . . . . . . . . . . .. 83 2 42 106 71 35 9359 . . . . . . . . . . . . . .. 97 2 49 93 70 Z3 9379 . . . . . . . . . . . . . .. 75 4 19 64 43 21 9384 . . . . . . . . . . . . . .. 68 2 34 76 51 25 9691 . . . . . . . . . . . . . .. 66 2 33 76 74 Z 10603 . . . . . . . . . . . . . .. 100 2 50 166 133 33 12594 . . . . . . . . . . . . . .. 95 4 24 77 34 43 12599 . . . . . . . . . . . . . .. 91 4 23 83 42 4] 12661 . . . . . . . . . . . . . .. 99 2 50 109 43 66 12674 . . . . . . . . . . . . . .. 72 2 36 88' 27 61 12674 . . . . . . . . . . . . . .. 62 2 31 88 29 59 12676 . . . . . . . . . . . . . .. 92 2 46 123 56 67 12679 . . . . . . . . . . . . . .. 64 2 32 I 84 31 53 12679 . . . . . . . . . . . . . .. 90 2 45 84 31 53 17746 . . . . . . . . . . . . . .. 91 2 46 93 30 63 17746 . . . . . . . . . . . . . .. 89 2 45 93 19 74 18225 . . . . . . . . . . . . . .. 90 2 45 79 59 20 18539 . . . . . . . . . . . . . .. 87 2 44 51 39 12 18539 . . . . . . . . . . . . . .J 100 2 50 51 31 20 18541 . . . . . . . . . . . . . .. 75 2 38 45 20 25 18541 . . . . . . . . . . . . . .. 82 2 41 45 35 10 18544 . . . . . . . . . . . . . .. 100 2 50 61 23 38 18544 . . . . . . . . . . . . . .. 85 I 2 l 43 P 61 22 39 Average group 51-100. 78 37 84 30 335 . . . . . . . . . . . . . .. 127 2 64 115 96 19 821 . . . . . . . . . . . . . .. 102 5 20 131 77 54 850 . . . . . . . . . . . . . .. 141 1 141 187 69 113 932 . . . . . . . . . . . . . .. 198 2 99 282 139 143 119 . . . . . . . . . . . . . .. 194 3 65 220 77 143 1123 . . . . . . . . . . . . . .. 184 2 92 231 54 177 1124 . . . . . . . . . . . . . .. 167 2 84 178 61 117 1126 . . . . . . . . . . . . . .. 139 4 35 109 73 36 1129 . . . . . . . . . . . . . .. 127 2 64 75 58 17 1133 . . . . . . . . . . . . . .. 106 2 53 130 66 64 1134 . . . . . . . . . . . . . .. 193 3 64 149 64 85 1139 . . . . . . . . . . . . . .. 101 2 51 107 56 51 1205 . . . . . . . . . . . . . .. 161 2 81 241 151 90 1587 . . . . . . . . . . . . . .. 125 6 21 67 31 36 1588 . . . . . . . . . . . . . .. 138 6 23 102 40 62 1590 . . . . . . . . . . . . . .. 160 5 32 97 53 44 1594 . . . . . . . . . . . . . .. 194 5 39 52 52 0 1926 . . . . . . . . . . . . . .. 163 1 163 244 150 94 1931 . . . . . . . . . . . . . .. 109 2 55 170 69 101 1932 . . . . . . . . . . . . . .. 107 2 54 123 70 53 1934 . . . . . . . . . . . . . .. 134 1' 134 267 208 59 1935 . . . . . . . . . . . . . .. 163 1 163 242 169 73 1956 . . . . . . . . . . . . . .. 180 6 30 105 71 34 2341 . . . . . . . . . . . . . .. 123 2 62 153 93 60 2341 . . . . . . . . . . . . . .. 162 2 81 153 96 56 2342 . . . . . . . . . . . . . .. 159 3 53 132 74 58 2347 . . . . . . . . . . . . . .. 121 3 40 148 49 99 2348 . . . . . . . . . . . . . .. 176 4 44 91 47 44 __..- In-aa EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL 13 Table 4 (Con.) Details of experiments, in parts per million of active potash. Active Potash Laboratfly N0‘ Crlgps 8196;: 5136p Before After Loss Cropping Cropping 2352 . . . . . . . . . . . . . .. 112 4 28 140 61 79 2410 . . . . . . . . . . . . . .. 101 3 34 112 53 59 2825 . . . . . . . . . . . . . .. 124 4 31 117 90 27 2826 . . . . . . . . . . . . . .. 195 3 65 92 69 23 2830 . . . . . . . . . . . . . .. 142 2 71 151 96 55 2830 . . . . . . . . . . . . . .. 162 3 54 151 96 55 2948 . . . . . . . . . . . . . .. 139 2 70 86 44 _ 42 3339 . . . . . . . . . . . . . .. 111 2 56 280 164- 116 3340 . . . . . . . . . . . . . .. 187 2 94 246 150 96 3350 . . . . . . . . . . . . . .. 105 4 26 154 47 107 3655 . . . . . . . . . . . . . .. 179 10 17 91 40 51 3655 . . . . . . . . . . . . . .. 158 8 19 91 57 34 3663 . . . . . . . . . . . . . .. 140 3 47 153 118 35 3975 . . . . . . . . . . . . . .. 104 2 52 81 61 20 4597 . . . . . . . . . . . . . .. 170 10 17 124 48 76 4597 . . . . . . . . . . . . . .. 193 10 19 124 40 84 4603 . . . . . . . . . . . . . .. 155 1 155 359 197 163 4644 . . . . . . . . . . . . . .. 141 4 35 143 51 92 5700 . . . . . . . . . . . . . .. 116 9 13 58 35 23 5700 . . . . . . . . . . . . . .. 110 10 11 58 44 14 5711 . . . . . . . . . . . . . .. 171 9 19 93 65 28 5711 . . . . . . . . . . . . . .. 157 9 17 93 75 18 5946 . . . . . . . . . . . . . .. 136 4 34 140 43 97 5968 . . . . . . . . . . . . . .. 114 9 13 118 30 88 6269 . . . . . . . . . . . . . .. 108 10 10 57 36 21 6269 . . . . . . . . . . . . . .. 101 10 10 57 39 18 6881 . . . . . . . . . . . . . .. 188 4 47 139 34 105 7092 . . . . . . . . . . . . . .. 165 4 41 136 60 76 7357 . . . . . . . . . . . . . .. 157 4 39 104 73 31 8815 . . . . . . . . . . . . . .. 172 2 86 61 46 15 8815 . . . . . . . . . . . . . .. 122 2 61 88 63 25 8816 . . . . . . . . . . . . . .. 126 4 31 34 32 2 8835 . . . . . . . . . . . . . .. 170 4 42 101 66 35 9040 . . . . . . . . . . . . . .. 102 2 51 96 47 49 9042 . . . . . . . . . . . . . .. 143 4 36 100 52 48 9043 . . . . . . . . . . . . . .. 147 4 37 108 97 11 9173 . . . . . . . . . . . . . .. 110 4 27 116 74 42 9175 . . . . . . . . . . . . . .. 149 2 75 225 196 29 9308 . . . . . . . . . . . . . .. 162 2 81 175 133 42 9308 . . . . . . . . . . . . . .. 114 2 57 175 140 35 9313 . . . . . . . . . . . . . .. 141 2 71 169 142 27 9328 . . . . . . . . . . . . . .. 112 2 56 212 174 38 9328 . . . . . . . . . . . . . .. 183 2 92 212 149 63 9335 . . . . . . . . . . . . . .. 132 2 66 161 90 7 9335 . . . . . . . . . . . . . .. 192 2 96 161 93 68 9350 . . . . . . . . . . . . . .. 153 4 38 111 88 23 9352 . . . . . . . . . . . . . .. 157 4 39 155 120 30 9359 . . . . . . . . . . . . . .. 150 2 75 93 67 26 9354 . . . . . . . . . . . . . .. 151 2 76* 106 74 32 9377 . . . . . . . . . . . . . .. 132 2 66 138 49 89 9385 . . . . . . . . . . . . . .. 132 2 66 115 78 37 9691 . . . . . . . . . . . . . .. 136 2 68 76 47 29 10603 . . . . . . . . . . . . . .. 179 2 90 166 133 33 12498 . . . . . . . . . . . . . .. 133 4 33 81 68 13 12499 . . . . . . . . . . . . . .. 126 4 32 64 56 3 14 BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION Table 4 (Con.) Details of experiments, in parts per million of active potash- Active Potash Laboratory N0. Gggps $1965); 556p Before After Loss Cropping Cropping 12500 . . . . . . . . . . . . . .. 113 4 28 60 41 19 12500 . . . . . . . . . . . . . .. 101 4 25 60 35 -25 12504 . . . . . . . . . . . . . .. 169 4 42 170 121 49 12505 . . . . . . . . . . . . . .. 199 4 50 132 111 21 12512 . . . . . . . . . . . . . .. 187 4 47 141 72 69 12512 . . . . . . . . . . . . . .. 135 4 34 141 57 84 12513 . . . . . . .{ . . . . . .. 157 4 39 904 48 42 12513 . . . . . . . . . . . . . .. 146 4 37 90 53 37 12519 . . . . . . . . . . . . . .. 153 4 38 100 70 30 12519 . . . . . . . . . . . . . .. 153 4 38 100 81 19 12586 . . . . . . . . . . . . . .. 170 4 42 193 53> 140 12586 . . . . . . . . . . . . . .. 177 4 44 193 48 145 12587 . . . . . . . . . . . . . .. 162 4 41 160 85 75 12587 . . . . . . . . . . . . . .. 134 4 34 160 77 83 12589 . . . . . . . . . . . . . .. 177 4 44 171 54 117 12589 . . . . . . . . . . . . . .. 199 4 50 171 50 121 12590 . . . . . . . . . . . . . .. 176 4 44 166 65 101 12590 . . . . . . . . . . . . . .. 176 4 44 166 69 7 12591 . . . . . . . . . . . . . .. 136 4 34 89 72 17 12592 . . . . . . . . . . . . . .. 198 4 49 161 54 107 12592 . . . . . . . . . . . . . .. 145 4 36 161 52 109 12593 . . . . . . . . . . . . . .. 139 4 35 86 40' 46 12593 . . . . . . . . . . . . . .. 157 4 39 86 47 39 12594 . . . . . . . . . . . . . .. 107 4 27 77 36 41 12595 . . . . . . . . . . . . . .. 116 4 29 73 42 31 12597 . . . . . . . . . . . . . .. 163 4 41 121 46 75 12597 . . . . . . . . . . . . . .. 155 4 39 121 50 71 12598 . . . . . . . . . . . . . .. 119 4 30 108 29 79 12598 . . . . . . . . . . . . . .. 122 4 31 108 44 64 12599 . . . . . . . . . . . . . .. 107 4 27 83 33 50 12641 . . . . . . . . . . . . . .. 158 4 39 134 53 81 12641 . . . . . . . . . . . . . .. 168 4 42 134 48' 96 12655 . . . . . . . . . . . . . .. 137 2 69 148 53 95 12655 . . . . . . . . . . . . . .. 133 2 67 148 65 83 12656 . . . . . . . . . . . . . .. 126 2 63 125 45 80 12656 . . . . . . . . . . . . . .. 130 2 65 125 45 80 12661 . . . . . . . . . . . . . .. 106 2 53 109 41 68 12671 . . . . . . . . . . . . . .. 164 2 82 190 64 126 12671 . . . . . . . . . . . . . .. 151 2 76 190 63 127 12676 . . . . . . . . . . . . . .. 105 2 53 123 62 61 17501 . . . . . . . . . . . . . .. 162 2 81 256 163 93 17501 . . . . . . . . . . . . . .. 161 2 81 256 161 95 17717 . . . . . . . . . . . . . .. 175 2 87 114 65 49 17717 . . . . . . . . . . . . . .. 133 2 67 114 48 66 18206 . . . . . . . . . . . . . .. ‘178 2 89 128 53 75 18208 . . . . . . . . . . . . . .. 171 2 86 136 . 38 78 18223 . . . . . . . . . . . . . .. 171 2 86 78 33 45 18224 . . . . . . . . . . . . . .. 130 2 65 102 57 45 18227 . . . . . . . . . . . . . .. 142 2 71 65 19 46 18228 . . . . . . . . . . . . . .. 126 2 63 84 36 48 18228 . . . . . . . . . . . . . .. 124 2 62 84 54 30 18230 . . . . . . . . . . . . . .. 170 2 85 137 56 81 18230 . . . . . . . . . . . . . .. 172 2 86 137 64 73 18231 . . . . . . . . . . . . . .. 130 2 65 106 60 46 18233 . . . . . . . . . . . . . .. 166 2 83 134 69 65 EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL 15 Table 4 (Con.) Details of experiments, in parts per million of active potash. Active Potash Lab°rat°ry N“ Cggps $1966): (11:61: Before After I L°ss Cr0ppi£1g Qrgpping |___ 18235 ....! . . . . . . . . .. 154 2 77 68 15 53 18235 . . . . . . . . . . . . . .. 185 2 93 68 51 17 18537 . . . . . . . . . . . . . .. 170 2 85 108 30 78 18538 . . . . . . . . . . . . . .. 124 2 62 90 37 53 18538 . . . . . . . . . . . . . .. 111 2 56 90 20 70 18540 . . . . . . . . . . . . . .. 169 2 85 98 32 66 18540 . . . . . . . . . . . . . .. 196 2 98 98 43 55 18542 . . . . . . . . . . . . . .. 178 2 89 121 33 88 18542 . . . . . . . . . . . . . .. 173 2 87 121 68 53 18543 . . . . . . . . . . . . . .. 136 2 68 90 24 66 18546 . . . . . . . . . . . . . .. 166 2 83 130 53 77 19547 . . . . . . . . . . . . . .. 177 2 89 110 53 57 18548 . . . . . . . . . . . . . .. 175 2 88 101 45 56 18548 . . . . . . . . . . . . . .. 156 2 78 101 77 31 18210 . . . . . . . . . . . . . ..| 198 2 99 174 1 76 1 98 Average group 101-200 148 57 131 61 834 . . . . . . . . . . . . . .. 230 1 230 310 156 154 1138 . . . . . . . . . . . . . .. 210 5 42 151 104 47 1203 . . . . . . . . . . . . . .. 201 2 100 601 381 220 1207 . . . . . . . . . . . . . .. 241 3 80 252 131 121 1597 . . . . . . . . . . . . . .. 284 5 57 164 26 138 1928 . . . . . . . . . . . . . .. 296 1 296 429 276 153 1928 . . . . . . . . . . . . . .. 251 2 126 270 169 101 2822 . . . . . . . . . . . . . .. 253 4 63 198 99 99 2946 . . . . . . . . . . . . . .. 241 2 121 379 222 157 3332 . . . . . . . . . . . . . .. 267 4 67 126 49 77 3335 . . . . . . . . . . . . . .. 278 1 278 447 380 67 3345 . . . . . . . . . . . . . .. 247 2 124 319 168 151 3346 . . . . . . . . . ...... 204 1 204 273 160 113 3631 . . . . . . . . . . . . . ..\ 250(?) 3 83 300 234 66 3633 . . . . . . . . . . . . . .. 274 3 91 259 196 63 3662 . . . . . . . . . . . . . .. 270 2 135 242 133 109 5098 . . . . . . . . . . . . . .. 214 10 21 158 42 116 5098 . . . . . . . . . . . . . .. 202 10 20 158 43 115 6010 . . . . . . . . . . . . . .. 289 10 29 169 45 121 6010 . . . . . . . . . . . . . .. 221 10 22 169 56 113 7117 . . . . . . . . . . . . . .. 285 4 71 170 101 69 7108 . . . . . . . . . . . . . .. 201 4 50 181 36 145 7353 . . . . . . . . . . . . . .. 266 4 67 203 63 140 8837 . . . . . . . . . . . . . .. 204 4 51 105 100 5 9039 . . . . . . . . . . . . . .. 213 2 106 240 155 85 9175 . . . . . . . . . . . . . .. 239 2 120 225 131 91 9313 . . . . . . . . . . . . . .. 227 2 114 169 108 61 9327 . . . . . . . . . . . . . .. 261 2 131 273 188 85 9334 . . . . . . . . . . . . . .. 212 4 53 125 92 33 9380 . . . . . . . . . . . . . .. 285 4 71 261 84 177 9385 . . . . . . . . . . . . . .. 214 2 107 115 65 50 12498 . . . . . . . . . . . . . .. 238 4 59 81 46 35 12504 .....» . . . . . . . . .. 249 4 62 170 127 43 12514 . . . . . . . . . . . . . .. 213 4 53 105 41 64 12514 . . . . . . . . . . . . . .. 238 I 4 59 105 24 81 12518 . . . . . . . . . . . . . .. 215 4 54 166 62 104 12518 . . . . . . . . . . . . . .. 242 4 61 166 68 98 12520 . . . . . . . . . . . . . .. 258 4 65 136 84 52 16 BULLETIN NO. 325 TEXAS AGRICULTURAL EXPERIMENT STATION Table 4 (Con.) Details of experiments, in parts per million of active potash. Active Potash Laboratory No- Cgélps 355p? I 555p "am-flea?" L0“ Cropping Cropping 12520 . . . . . . . . . . . . . .. 259 4 65 136 84 52 12521 . . . . . . . . . . . . . .. 277 4 69 167 79 88 12521 . . . . . . . . . . . . . .. 277 4 69 167 95 72 12576 . . . . . . . . . . . . . .. 299 4 75 178 131 47 12576 . . . . . . . . . . . . . .. 300 4 51 178 114 64 12577 . . . . . . . . . . . . . .. 263 4 66 181 112 . 69 12577 . . . . . . . . . . . . . .. 238 4 59 181 118 63 12578 . . . . . . . . . . . . . .. 261 4 65 221 78 143 12578 . . . . . . . . . . . . . .. 238 4 59 221 108 113 12579 . . . . . . . . . . . . . .. 205 4 51 166 61 105 12579 . . . . . . . . . . . . . .. 207 4 52 166 90 76 12640 . . . . . . . . . . . . . .. 248 4 62 183 121 62 12588 ...s . . . . . . . . . .. 274 4 68 281 66 215 12642 . . . . . . . . . . . . . .. 227 4 57 133 85 48 12642 . . . . . . . . . . . . . .. 207 4 52 133 74 59 12648 . . . . . . . . . . . . . .. 248 4 62 208 138 70 12648 . . . . . . . . . . . . . .. 274 4 68 208 146 62 12652 . . . . . . . . . . . . . .. 215 2 108 265 146 119 12653 . . . . . . . . . . . . . .. 283 2 142 329 146 183 12658 . . . . . . . . . . . . . .. 242 2 121 232 131 101 12658 . . . . . . . . . . . . . .. 228 2 114 232 142 90 12659 . . . . . . . . . . . . . .. 247 2 124 325 145 180 12660 . . . . . . . . . . . . . .. 219 2 110 194 85 109 12660 . . . . . . . . . . . . . .. 226 2 113 194 92 102 12668 . . . . . . . . . . . . . .. 239 2 120 221 46 175 12668 . . . . . . . . . . . . . .. 232 2 116 221 64 157 17500 . . . . . . . . . . . . . .. 230 2 115 367 301 66 17500 . . . . . . . . . . . . . .. 242 2 .121 367 286 81 18205 . . . . . . . . . . . . . .. 207 2 104 158 58 100 18205 . . . . . . . . . . . . . .. 204 2 102 158 58 100 18207 . . . . . . . . . . . . . .. 241 2 121 162 86 76 18209 . . . . . . . . . . . . . .. 252 2 126 165 70 U5 18226 . . . . . . . . . . . . . .. 288 2 144 239 95 144 18229 . . . . . . . . . . . . . .. 201 2 100 147 49 98 18229 . . . . . . . . . . . . . .. 237 2 119 147 60 87 18232 . . . . . . . . . . . . . .. 253 2 127 201 99 102 18232 . . . . . . . . . . . . . .. 240 2 120 201 119 82 18536 . . . . . . . . . . . . . .. 299 2 150 291 80 211 18546 . . . . . . . . . . . . . .. 201 2 100 130 I 70 | 60 Average group 201-300 242 94 209 100 818 . . . . . . . . . . . . . .. 300 2 150 274 99 175 832 . . . . . . . . . . . . . .. 350 2 175 271 64 207 982 . . . . . . . . . . . . . .. 354 219 195 24 1577 . . . . . . . . . . . . . .. 329 4 82 207 102 105 1927 . . . . . . . . . . . . . .. 400 3 133 300 161 139 2340 . . . . . . . . . . . . . .. 358 3 119 278 94 184 2828 . . . . . . . . . . . . . .. 392 3 131 308 160 148 2959 . . . . . . . . . . . . . .. 331 3 110 500 312 188 3632 . . . . . . . . . . . . . .. 332 3 111 311 165 146 5960 . . . . . . . . . . . . . .. 366 2 183 243 65 178 7148 . . . . . . . . . . . . . .. 374 4 94 203 43 180 9045 . . . . . . . . . . . . . .. 304 2 152 561 436 125 9167 . . . . . . . . . . . . . .. 371 2 186 324 178 146 9672 . . . . . . . . . . . . . .. 358 2 179 399 207 192 EFFECT OF CROPPING UPON THE ACTIVE POTASH OF THE SOIL 17 Table 4 (Con.) Details of experiments, in parts per million of active potash. In F No of 1*‘ r111‘- Active Potash Laboratory No. Crops Crcips C1501» L°s5 Cropping Cropping 12503 . . . . . . . . . . . . . .. 342 4 86 160 85 75 12569 . . . . . . . . . . . . . .. 362 4 91 265 169 96 12571 . . . . . . . . . . . . . .. 335 4 84 100 72 28 12583 . . . . . . . . . . . . . .. 357 4 89 290 99 191 12585 . . . . . . . . . . . . . .. 400 4 100 390 166 224 12588 . . . . . . . . . ...... 309 4 77 281 48 233 12596 . . . . . . . . . . . . . .. 369 4 92 183 ' 77 106 12639 . . . . . . . . . . . . . .. 382 4 95 239 112 127 12639 . . . . . . . . . . . . . .. 357 4 89 239 80 159 12640 . . . . . . . . . . . . . .. 323 4 81 183 86 97 12647 . . . . . . . . . . . . . .. 323 4 81 270 72 198 12647 . . . . . . . . . . . . . .. 328 4 82 270 116 151 12649 . . . . . . . . . . . . . .. 352 4 88 256 161 95 12650 . . . . . . . . . . . . . .. 343 4 86 230 160 70 12650 . . . . . . . . . . . . . .. 348 4 87 230 120 110 12651 . . . . . . . . . . . . . .. 381 2 191 359 125 234 12652 . . . . . . . . . . . . . .. 313 2 157 265 118 147 12653 . . . . . . . . . . . . . .. 339 2 169 329 151 178 12657 . . . . . . . . . . . . . .. 394 2 197 367 201 166 12659 . . . . . . . . . . . . . .. 357 2 179 325 126 199 12678 . . . . . . . . . . . . . .. 329 2 165 574 348 226 17444 . . . . . . . . . . . . . .. 347 2 174 343 141 202 17444 . . . . . . . . . . . . . .. "360 2 180 343 186 157 18222 . . . . . . . . . . . . . .. 309 2 154 238 84 154 18536 . . . . . . . . . . . . . ..] 331 ‘ 2 I 166 | 291 ‘ 67 1 224 Average group 301-400] 348 127 290 153 1202 . . . . . . . . . . . . . ..] 450(?) 2 225 736 399 337 1580 . . . . . . . . . . . . . .. 451 6 75 657 205 452 2346 . . . . . . . . . . . . .., 452 2 226 224 50 174 3634 _ . . . . . . . . . . . . .. 430 2 215 243 165 78 9297 . . . . . . . . . . . . . .. 438 2 219 408 232 176 9381 . . . . . . . . . . . . . .. 453 4 113 408 100 308 12515 . . . . . . . . . . . . . .. 455 4 114 195 116 79 12515 . . . . . . . . . . . . . .. 460 4 1 115 195 132 63 12536 . . . . . . . . . . . . . .. 465 4 116 278 58 220 12536 . . . . . . . . . . . . . .. 497 4 124 278 66 212 12575 . . . . . . . . . . . . . .. 434 4 109 337 170 167 12584 . . . . . . . . . . . . . .. 488 4 122 386 169 217 12584 . . . . . . . . . . . . . .. 480 4 120 386 169 217 12643 . . . . . . . . . . . . . .. 483 4 121 441 273 168 12651 . . . . . . . . . . . . . .. 404 2 202 359 121 238 12657 . . . . . . . . . . . . . .. 411 2 206 367 201 166 12678 . . . . . . . . . . . . . .. 450 2 225 574 238 336 18234 . . . . . . . . . . . . . .. 416 2 208 289 106 183 18234 . . . . . . . . . . . . . ..[ 433 2 217 ‘ 289 I 133 I 156 Average group 401-500 451 159 361 199 3344 . . . . . . . . . . . . . .. 544 4 136 461 242 219 5940 . . . . . . . . . . . . . .. 523 4 131 464 276 188 6977 . . . . . . . . . . . . . .. 596 10 59 249 141 108 7373 . . . . . . . . . . . . . .. 597 4 149 271 101 170 9044 . . . . . . . . . . . . . .. 564 2 282 1409 816 593 9044 . . . . . . . . . . . . . .. 564 2 282 1409 726 693 13 BULLETIN NO. s25 TEXAS AGRICULTURAL EXPERIMENT STATION Table 4 (Con.) Details of experiments, in parts per million of active potash. A t" P ta. h Laboratory No" Cggps 18195;: gresp Beffazfle oAfster Loss Cropping Cropping 9382 . . . . . . . . . . . . . . . 573 2 287 561 170 391 12535 . . . . . . . . . . . . . . . 576 4 188 208 68 140 12568 . . . . . . . . . . . . . . . 509 4 127 270 163 107 12570 . . . . . . . . . . . . . . . 525 4 131 200 102 98 12573 . . . . . . . . ., . . . . . . 571 4 143 530 290 240 12574 . . . . . . . . . . . . . . . 576 4 184 434 202 232 12581 . . . . . . . . . . . . . . . 555 4 144 183 99 84 12582 . . . . . . . . . . . . . . . 596 4 144 275 170 105 12644 . . . . . . . . . . . . . . . 562 4 141 346 226 120 12649 . . . . . . . . @ . . . . . . 502 4 125 256 133 123 12677 . . . . . . . . . . . . . . . 503 2 252 540 175 365 12677 . . . . . . . . . . . . . . . 506 2 253 | 540 218 322 Average group 501-600 552 175 478 237 2956 . . . . . . . . . . . . . . . 700 4 175 629 329 300 5955 . . . . . . . . . . . . . . . . ‘616 2 308 1005 297 708 6977 . . . . . . . . . . . . . . . 658 10 65 249 142 107 12502 . . . . . . . . . . . . . . . 641 4 160 265 93 172 12516 . . . . . . . . . . . . . . . 618 4 154 295 130 165 12517 . . . . . . . . . . . . . . . 657 4 164 196 136 60 12517 . . . . . . . . . . . . . . . 619 4 155 196 103 93 12533 . . . . . . . . . . . . . . . 649 4 162 311 92 219 12533 . . . . . . . . . . . . . . . 658 4 164 311 108 203 12534 . . . . . . . . . . . . . . . 664 4 166 238 113 12")‘ -12573 . . . . . . . . . . . . . . . 614 4 154 530 320 210 12580 . . . . . . . . . . . . . . . 615 4 154 248 131 117 12580 . . . . . . . . . . . . . . . 646 4 162 248 109 139 12582 . . . . . . . . . . . . . . . 623 4 156 275 125 150 12646 . . . . . . . . . . . . . . . 633 4 158 485 332 I 153 ___ i | i Average group 601-700 641 163 365 195 1936 . . . . . . . . . . . . . . . 772 5 154 376 174 202 7147 . . . . . . . . . . . . . . . 715 4 179 524 262 262 12516 . . . . . . . . . . . . . . . 735 4 184 ' 295 155 I 140 Average group 701-800 741 172 39s 201 5955 . . . . . . . . . . . . . . . 888 4 222 1005 224 781 12531 . . . . . . . . . . . . . . . 880 4 220 628 196 432 12572 . . . . . . . . . . . . . . . 877 4 219 ‘ 855 337 I 518 Average group 801-900 882 220 I 829 577 1929 . . . . . . . . . . . . . . . 981 5 196 491 176 315 12645 . . . . . . . . . . . . . . . 934 4 234 606 283 323 12645 . . . . . . . . . . . . . . .‘ 977 4 I 244 l‘ 606 231 1 375 Av. group_ 901-1000. .| 964 I 225 I 568 PUBLICATIONS AVAILABLE Order by NUMBER BULLETINS Cottonseed Meal as a Human Food (Technical)—-1910. Steer Feeding—1913. Composition and Digestibility of the Chloroform Extract of Texas Hays and Fod- ders (Technical)——1913. Digestion Experimets on men with Cottonseed Meal—1913. Ammonia-Soluble Inorganic Soil Colloids—1914. Digestion Experiments with Texas Feeding Stufifs——l9l4. Commercial Fertilizers and Their Use——l9 14. The Total Fatty Acids and Other Ether-Soluble Constituents of Feedstufis—1914. Texas Feeding Stuifs; Their Composition and Utilization—1914. Losses of Moisture and Plant Food by Perc0lation~—1914. Sudan Grass——1915. The Composition of the Soils of the Texas Panhandle—1915. The effect of Organic Compounds in Pot Experiments—1915. Distribution and Digestibility of the Pentosans of Feeds——1915. The effect of the Additions on Availability of Soil Phosphates-—1915. Oxidation of Organic Compounds in the Soil-——1915. Steer Feeding‘—1912. Moisture Relations. of Some Texas Soils-—1915. Cooperative Fertilizer Experiments with Corn——1908-14. The Production Co-Efficients of Feeds (Technical)-—1916. Fattening Lambs——-1916. Sprays and Spraying-1916. Tile Drainage—1916. The Composition of Cottonseed Meal and Cottonseed—1916. The Effects of Additions on the Availability of Soil Potash and the Preparation of Sugar Humus——1916. The Composition of Rice and Its By-Products—1916. Soils of Grayson, Lee, McLennan, Titus and Tyler Counties——1916, Japanese Sugar Cane as a Forage Crop—1916. Digestibility of Sugar, Starches, and Pentosans of Roughages—-1916. Progress Report, Substation No. 3, Angleton, Texas——1909-14. Progress Report, Substation No. 4, Beaumont, Texas, 1909-14. Peanut Meal and Ground Whole Pressed Peanuts for Hogs—1916. The Productive Values of Some Texas Feeding Stuffs——1916. The Recurving of Milo and some Factors Influencing It. Poultry Houses and Poultry Equipment for Texas——1917. The Fig in Texas——1917. I Progress Report, Substation N0. 2, Troup, Texas, 1909-14. Barns for Work Animals—1917. Field Experiments with Crown Gall—1913-17. The Availability of Phosphoric Acid in Rock Phosphate—1917. The Composition of the Soils of South Central Texas——1917. Progress Report, Substation No. 1, Beeville, Texas—-1910-14. Progress Report, Substation No. 5, Temple, Texas—1910-14_ Progress Report, Substation No. 7, Spur, Texas—1909-14. Progress Report, Substation No. 8, Lubbock, Texas——1910-14. Progress Report Substation No. 9, Pecos, Texas—1910-l4. The Composition of Peanuts and Peanut By-Products—-—1917. The Influence of Peanuts and Rice Bran on the Quality of Pork——1918. Cooperative Soft Pork Investigations—-1918. Studies of the Harlequin Bug—1918. The Influence of Peanut Meal on the Quality of Pork—l9l8. Experiments at Substation No. 3, Angleton, Texas——1909-l6. The Beemoth or Waxworm—l9l8. Mineral Requirements of Sheep——1918. Grain Sorghum Improvement—1918. The Utilization of Yucca for the Maintenance of Cattle-——l9l8. The Need of Texas Soils for Lime—-1919. Composition of the Soils of Archer, Franklin and Harrison Counties——19l£l. Feeding Values of Certain Feeding Stuifs—1919. The Chemical Composition of the Cotton Plant—1919. Report of Experiments at Substation No. 4. Beaumont, Texas—-1915-l8. Nitrification in Texas Soils (Technical)-—1920. The Searing Iron vs. the Knife for Docking or Detailing Lambs—1920. Rations for Fattening Steers——1920. Grain Sorghum vs. Corn for Fattening Lambs—1920. A Study of the Black and Yellow Molds of Ear Corn—-—1920. Spur Feterita——1921. Sweet Potato Fertilizer Experiments at Substation No. 2-4192]. Type and Variability in Kafir (Technical)—1921. Composition and Feeding Value of Wheat By-Products—192l. Rice Bran for Fattening Hogs——1922. Shelling Percentages in Grain Sorghum-—1922. Grain Sorghum vs. Corn for Fattening Baby Beeves—-l922. (Technical)-—-1917. An Economic Study of a Typical Ranching Area on the Edwards Plateau of Texas --1922. Swine Feeding Experiments——-1923. Giain Sorghum vs. Corn for Fattening Lambs—-1923. Texas Root Rot of Cotton and Methods of its Control—1923. The Sweet Potato Weevil—1923. I. Fattening Steers on Cottonseed Hulls With and Without Corn.——ll. The In- fluence of Age on Fattening Steers—-1923. The Interpretation of Correlation Data—-—1923. The Influence of Individuality, Age and Season upon the Weights of Fleeces Pro- duced by range Sheep—-1923. Commercial Fertilizers in 1922-23. Rice Bran and Rice Polish for Growing and Fattening Pigs——1923. Commercial Feeding Stuffs Sept. 1, 1922 to Aug. 31, 1923. Digestion Experiments with Oat By-Products and other Feeds, Report No. 7——1924. The Soils of Brazos, Camp, Ellis and Washington C0unties—1924. Comparative Influences of Various Protein Feeds on Laying Hens-1924. The Relation between Rents and Agricultural Land Values in Theory and in Prac- tice-—1924. Field and Laboratory Notes on a fatal Disease of Cattle Occurring on the Coastal Plains of Texas (Loin Disease)——1924. The Influence of Individuality, Age and Season upon the Weights of Fleeces Pro- duced by Angora Goats under Range Conditions—-—1924. Cotton Variety Experiments at the Main Station—1912 to 1922. (‘ommercial Fertilizers in 1923 and 1924. The Price of Feed Utilities. . CIRCULARS Strawberries Under Irrigation in South Texas-——1914. Insect Enemies of Sudan Grass-—1915. Housing IParm Implements——1915. The San Jose Scale—-1916. The Malvaceous Plants of Texas—1920. Cost of Production; Its Relation to Price—1920. The Practicability of the Milking Machine——1923. Standard Fertilizers and their Use (Reprint)—1923. Cotton Boll Weevil Control in Texas——1924. Texas Agricultural Experiment Station System—1924. The Lower Rio Grande Jalley of Texas. Suggestions on Queen Rearing. Foulbrood Control and Disases of Bees-—Foulbro0d Law and Revised Regulations. ANNUAL REPORTS 25th for 1912; 26th for 1913; 27th for 1914; 28th for 1915; 29th for 1916; 32nd for 1919. Address all communications to B. YOUNGBLOOD, Director, Agricultural Experiment Station, Agricultural and Mechanical College of Texas, College Station, Texas.