TEXAS AGRICULTURAL EXPERIMENT STATION R. D. LEWIS, Director College Station, Texas BULLETIN NO. 683 OCTOBER, 1946 COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON Division of Agricultural Engineering . and Division 0f Agronomy in Cooperation with the Production and Marketing Administration, U. S. Department of Agriculture AGRICULTURAL AND MECHANICAL COLLEGE OF TEXAS GIBB GILCHRIST, President / VB26-1046-7M-L180 _ cotton trade has looked with disfavor 0n the rougher methods of ting cotton, such as hand-snapping and machine harvesting both e picker type and the stripper type mechanical harveste-rs. This gely because the lint from theroughly harvested cottons contained yforeign matter than cotton picked by hand. Textile workers have Y t that the manufacturing or spinning performance of cottons har- v by hand-snapping, machine-stripping, and machine-picking would y nferior quality "as compared with the manufacturing and spinning ' ance of hand-picked cotton. ftudy was made covering a three-year period, 1943-1945, of the effects 0d of harvesting on the spinning performance. The four harvesting 6-,: used were: hand-picked, hand-snapped, machine-picked and ma- Ttripped. Each of the four methods was used in harvesting four f es of cotton which were selected because of their widely differing properties. ‘ conducted during 1943, 1944 and 1945 at both College Station and - show that the difierence in the percentage of burs and trash ed from cotton harvested by hand-snapping and by machine-stripping significant. However, when varieties are comparedone with another Terence in the_ content of the burs and waste is significant. More ‘A and trash were removed in the cleaning and ginning of cotton th'at machine-picked. In the cleaning and ginning processes more wand trash were removed from short staple, hand-picked cotton than fthe longer staple cottons thatwere harvested by hand-snapping and A harvesting. Since the machine-picked and hand-picked samples _'_-1 no burs they were not run through an extractor prior to ginning 1..- the case with the hand-snapped and machine-stripped cotton, which tain burs. 'V properties, and classers staple length were not appreciably affected method of harvest. The grade, however, was significantly afiected i‘ method of harvest. The hand-picked cottons averaged one to» two higher than the other methodsof harvesting. spinning tests show that the most important factor of manufac- quality as affected’ by method of harvesting is that of the amount -. or foreign matter in the lint. the manufacturing processes there was a significant increase in picker = = d waste for roughly harvested,cotton as compared with hand- cotton, especially for the longer staple cottons. Relatively small i ces were found in picker and card waste content between the hand- 1» samples and the machine-harvested samples of the short staple esting except for a slight lowering of the appearance grade fo-r ger and finer fibered cottons. ~ quality of the yarn manufactured was not affected bythe method‘ \ CONTENTS Introduction . . , . .' . . . . . .- . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . “ Agronomic Aspects . . . Varieties . . . . . . . . . . . . . . . . . . . . . .- . . . . . . . . . . . . . . . . . . . . . . . . . . . _ Height of Plant ‘ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Harvesting . . . . . . . . . . . . . . . . . . . . . . . . . . . . .' . . . . . . . . . . . . . . . . . . Extracting . . . . . . . . ~. .- . . . . . . . . . . . . . . . . . . . . . .. . . . . . . . . . . . . . . . ._ Cleaning and Ginning_ . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ~ . . . . Waste Removed in Extracting, Cleaning and Girining . . . . . . . . . .. .~.'l I‘: Waste Removed by Extracting . . . . . . . . . . . . . . . . . . . . . . . . Waste Removed in Cleaning and Ginning - . . . . . . . . . . . . . . . . Fiber Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . Spinning Tests . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . ._ . . . . . . . . Summary and Conclusions . . . . . . . . . . . . . . . . . . . . . . . . . . . .' . . . . . . . .. .i Acknowledgments . . , . . . . . . . . . . . . . . . . . . . . . . . . . .» . . . . . . . . . . . . . . . l BULLETIN N O. 683 , OCTOBER, 1946 COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON H. P. SMITH, Chief, Division of Agricultural Engineering JOSEPH T. ROUSE, Cotton Technologist, Production and Marketing Ad- ministration, USDA D. T. KILLOUGH, Agronomist, Cotton Breeding, Division of Agronomy D. L. JONES, Superintendent, Substation No. 8, Lubbock, Texas The cotton trade has looked with disfavor on hand-snapping and machine harvesting of cotton. Often the farmer has suffered price penalties because of the method of harvesting. In the January, 1943, issue of Textile World, the statement was made that, “no spinning tests are available on machine- picked cotton, so for all practical purposes the mechanical picker cannot be universally accepted until such tests are made and until they meet the spinners’ requirements.” Therefore, in 1943 the Texas Agricultural Ex- periment Station and the Production and Marketing Administration of the U. S. Department of Agriculture began a study to determine the A effects on the comparative spinning qualities of cotton harvested by three difierent methods, namely, hand-picking, hand-snapping, and machine- stripping. No mechanical picker was available in 1943. In- 1944, through the cooperation of the International Harvester Company, a fourth method of harvesting, machine-picking, was included in the study. The results of three years’ work, 1943-1945, are given in this bulletin. ' AGRONOMIC ASPECTS The work was done at College Station in east Central Texas and at Lubbock in Northwest Texas. These areas differ greatly in climatic con- _ ditions, such as the amount of rainfall, the number of days between frosts, and the temperatures, particularly the night atmosphere. There is also a difference in the soil type and the altitude of the two locations. Lubbock is located on the High Plains in Northwest Texas approximately 500 miles northwest of College Station. All of these factors affect the development of the plant, making a difference in the height of the plant, the length of the fruiting and vegetative branches, and in general, the development of y, the plant. Varieties Varieties of cotton differing widely in their fiber properties were selected for the study in 1943: Hi-Bred, because of its short, coarse staple, and i Deltapine because of its medium staple. In 1944, the varieties were changed to include the more commonly grown varieties: Hi-Bred, Delta- pine, Rogers Acala and Macha. Macha was selected for its stormproof qualities and suitability for machine stripping. Rogers Acala was selected I from 18%‘, inches for Macha to 23 inches for Rogers Acala. 6' BULLETIN NO. 683, TEXAS AGRICULTURAL EXPERIMENT STATION because of its longer staple and good spinning qualities. These same _ varieties were grown in 1945 at both College Station and Lubbock. Height of Plants College Station.—The growth and size of the plants of the varieties ' at College Station were about normal in 1943 and 1944 and varied little l between varieties. In 1945, however, the plants at College Station were larger than normal plants and more foliage was collected in harvesting . with the machines, particularly with the stripper. The plant height for Hi-Bred and Deltapine for the years 1943 and 1944 was approximately 27 inches. The three-year average for these two varieties, however, was approximately 30 inches. inches in height respectively for the three years. Lubbock-At Lubbock, where the cottons were grown under conditionsf of less rainfall, the plants were much smaller. The average height ranged for all four varieties for the three-year period was approximately 20 inches. Yields Yields for the various varieties at each of the locations also varied. At College Station, the three-year average yield of lint for the different varieties was slightly less than 300 pounds per acre while at Lubbock the average yield for all varieties was approximately 400 pounds of lint per " acre. Harvesting Conditions, Dates of Harvest and Defoliation In 1943, at College Station, the Hi-Bred and Deltapine varieties were quite fiuffy at harvest time. In 1944, rains occurring at frequent intervals created a damp condition which caused the boll stem and bur to become rotten and brittle and easy to break off. The locks of cotton in the bur 5' for all varieties were also quite compact and more difiicult to pick, especially with a mechanical picker. In 1945, somewhat similar conditions of bolls and cotton existed, and in addition the plants were much larger and were covered with heavy, tender growth of foliage. Because of the extreme storm resistance of the Macha cotton and because it was not suited to machine-picking, no effort was made to use the mechanical picker on this variety in 1945 at either of the two locations. ' The conditions under which the cottons were harvested at Lubbock during each of the three years were quite similar and the varieties, with the exception of Macha, were fairly fiuffy. All the varieties at the time of harvest at Lubbock were well matured with practically all bolls open. At College Station, _the cotton was harvested by the various methods on September 9 in 1943 and on September 14 in 1944. In 1945, however, the hand-picked, hand-snapped, and machine-picked cottons were harvested on September 18. The stripped samples were not harvested that year until October 11 because a tractor was not available on which to mount the stripper. Rogers Acala and Macha averaged 31 and 32 The average Z >~\1_n!lRA\'Al u. t... , ». . COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 7 x At Lubbock, in 1943, the samples were harvested on October 20, which is earlier than usual. The plants had matured early and calcium cyanamid (defoliant) was applied to remove the leaves, thus exposing the bolls to sunshine so that they opened earlier and were ready for harvest two or three weeks before‘ frost. In 1944 and 1945, the cottons were harvested on November 8. During each of these two years calcium cyanamid had also been applied to the plants to remove the leaves. The cottoniin 1944 and 1945, however, didx not mature as early as in 1943 which accounts for the later date of harvest. . Defoliant was also applied to the cotton plants at College Station each year, but rather poor results were obtained in 1943 and 1945. In 1943 dry weather apparently prevented good defoliation. In 1945, heavy rains occurring prior to the time the cyanamid was applied caused the plants to put on new growth and even though the old foliage was removed by the defoliant, a new growth occurred’ with such rapidity that by the time the stripper was used the plants were practically in full foliage. This caused an excessive amount of green leaf to be. collected in“ harvesting the cotton with the stripper. Very little green leaf was collected in har- vesting the cotton at College Station in 1944. At Lubbock, good defoliation was obtained each year and practically no green leaf was collected in harvesting the cottons with either type of machine. / ENGINEERING ASPECTS The engineering aspects of this study can be divided into three sections; namely, harvesting, extracting, andcleaning and ginning. Harvesting Generally, the hand-harvested cottons, both the picked and snapped, were harvested one or two days before the cottons were harvested with the machines. Ordinary labor was used to pick and snap the samples at both College Station and Lubbock. - All of the machine-stripped samples were harvested with the Texas Station Harvester, developed by the Texas Agricultural Experiment Sta- tion,1 at each location each year, with the exception of 1945 at Lubbock when a two-row, tractor mounted, John Deere Stripper was used. The machine-picked samples at Lubbock in 1944 were harvested with an Inter- national Harvester low-drum picker. The samples machine-picked at Col- lege Station in 1944 and 1945 were harvested with an International Har- vester high-drum type of picker. ' Extracting All the hand-snapped and machine-stripped samples- harvested at College Station were extracted with the Texas Station Bur Extractor? The hand- 1Texas Station Bulletins 452, 511 and 580. 2Texas Station Bulletins 511 and 580. _ Variety _. _ Harvest method _ 7i Hi-Bred Macha Deltaplne Rogers Acala College Station v Hand-snapped . . . . . . . . . . . . . 34.0 l 33.6 1 36.3 37.7 .Machine-stripped . . . . . . . . .. 34.0 30.7 ‘ 36.0 37.1 Lubbock Hand-snapped . . . . . . . . . . . . . 31.0 21.0 29.6 29.6 Machine-stripped . . . . . . . . . . 28.5 22.6 . 28.2 29.1 8 BULLETIN NO. 683. TEXAS AGRICULTURAL EXPERIMENT STATION snapped and machine-stripped samples harvested at Lubbock in 1943 1944 were extracted with the Texas Station bur extractor, but the samp harvested in» 11945 were extracted with a Mitchell gin stand extractor.‘ Cleaning and Ginning After the samples of uncleaned seed cotton from all of the methods," harvesting had been extracted they were bagged and shipped to the Cotton Field Station at Stoneville, Mississippi, for cleaning and ginn‘ When the cotton had been cleaned and ginned it was then shipped to U. S. Cotton Testing Laboratory at College Station, Texas, for the v5“? and spinning tests. WASTE REMOVED IN EXTRACTING, CLEANING, AND GINNIN Hand-snapped and machine-stripped cotton requires two processing tre ments to remove ‘the Waste before the cotton is ginned. The first tr ment removes the burs and loose dirt and trash. This,is done with spec" bur extracting equipment and before any cleaning is done. The sec" treatment, using special cleaning machinery, removes much of the fore’ matter left in the seed cotton by the extractor. Additional amounts trash and waste in the cotton are removed in the actual ginning proce the gin throwing off by centrifugal force a large percentage of the mo and waste material. Waste Removed by Extracting ’ The data in Table 1 show that the average percentage of burs and was removed by extracting in the field harvested, hand-snapped and machi stripped cotton, amounts to approximately one-fourth to one-third of th Z total. The bulk of this weight is burs. The data do not show any significant- differences in the precentage of waste for the two methods of harvesting; when the same variety is considered. There is a greater range in th percentage of waste between varieties and between locations than between the methods of hand-snapping and machine-stripping. ‘l. Table 1. Percentage of the original sample removed as waste and burs from field harvested" hand-snapped and machine-stripped cotton grown at College Station and Lubbock, 1943-1945 COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON Waste Removed in Cleaning and Ginning 9 The percentage of waste removed in the cleaning and ginning operations is shown in Table 2, and graphically in Figure 1. In studying the data and by referring to Figure 1, it is seen that a higher percentage of the total amount of motes and trash was removed from the machine-picked cottons at both College Station and Lubbock than from cotton harvested by hand-snapping, hand-picking and machine-stripping. Ordinarily, it is expected that the rougher methods of harvest, such as hand-snapping "and machine-stripping, would have a higher percentage of waste. The datav Table 2. Percentage of the seed cotton removed as waste in cleaning and ginning four varieties of cotton grown at College Station and Lubbock and each harvested by four methods, 1943-1945 Variety Harvest method Percent of motes and trash removed 1 943 1944 19.45 Average College Station Hi-Bred Macha Deltapine Rogers Acala - Hand-picked Hand-snapped M achine-picked M achme-stripped Hand-picked Hand-snapped Machine-picked Machine-stripped Hand-picked Hand-snapped Machine-picked Machine-stripped Hand-picked Hand-snapped . Machine-picked Machine-stripped »~mw wamq mimw wmmm ueoq ewmw -wm meow b! UNJOJUJ Qflflfiab \l C500 CHOHQG lnllsbolo wwono is ‘lain comm-d mmpw mwmm mzuw Aqua rP@W wmwo mwwm mwwm Lubbock Hi-bred Macha Deltapine Rogers Acala Hand-picked Hand-snapped M achine-picked Machine-stripped Hand-picked Hand-snapped Machine-picked Machine-stripped Hand-picked Handjsnapped Machine-picked Machine-stripped Hand-picked Hand7snapped Machine-picked Machine-stripped QKIbO-‘lubfifl OOUHQOOOON fhfhvbbi OOQQHO <0 O0 wqwoa u-ukl-n-n MOOF-‘CD l-‘QOW O? O huh v-ewwwwllL-b: LE,»- o-n O bPbbM \1\1U\OJ tblP- nlifivhoh “wow wove W ow 9e¢~ 10 BULLETIN NO. 683, TEXAS AGRICULTURAL EXPERIMENT STATION obtained in this study do not show this to be true. It is interesting to i note that hand-picked Hi-Bred samples had a higher percentage of motes: and trash than did either the hand-snapped or machine-stripped samples 31 for each of the locations. It can be expected that the extracting equip- j ment will do a certain amount of cleaning in conjunction with the extractw‘ ing process. The hand-picked and the machine-picked samples did not I contain burs and, therefore, were not treated in any manner to remove foreign material between the harvesting and the cleaning and ginning ' operation. This, no doubt, affected the percentages of motes and trash; in the cotton harvested by these two different methods. 5’ Fiber Tests As stated in the foregoing sections, the cotton varieties used in this j study were chosen because their generally known fiber characteristics represent a relatively wide difference infiber properties. Each variety of cotton, by each method of harvesting at each of the two locations, was ' classified for grade and staple, and was measured on the fibrograph for V, upper half mean length, mean length, and uniformity ratio. It was assumed a that since fineness, maturity, and fiber strength are mainly varietal prop- erties, and to only a limited extent are affected by environmental condi- a College station muggy 4 ,. l _ I I . I _ i m .. == : 11 m _. . ~41 Q - 1 F" g’ 1 b- T 5 I I I 3 a _ A .5: ‘El E‘ 3 it s?‘ s! 3 . 3 a: E315 vi»: t: .1 r: ‘as? 2*’ -l o i... s." £221: s‘; .1“ i as: s1: a a =1 fllé 3851'» $8 3S ' §~~ 5?: , u as 75¢ ?ffifi F" no g 13g g3 ' ..1 A n 2" " "‘ I-'~' 0w: 812% go? o5 a '3 “fig ma! ml: §§§§ ii i? i 5g; mg; l Iii-bred _ lube Doltepinp , Raga-n Ace}: lhehe Delitupine Roger? no‘); / i viarirn‘ ’ g Figure 1. Percentage of seed cotton removed as waste in cleaning‘ and ginning four varieties. of cotton grown at College Station and Lubbock and each harvested by four“: \ methods, 1943-1945. COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 11 tions, they would not be affected by the methods of harvesting. Accord- ingly, only the hand-picked cottons of 1943 were measured for these properties. Because of the possibility of mechanical damage in harvesting and ginning of the non-hand-picked cottons, it was deemed desirable to measure the strength of the fiber for each method of harvesting for the 1944 and 1945 crops. Detailed classification and fiber test results are listed in Table 3 according to location, variety, and method of harvesting. Results indicate that method of harvesting very definitely affected the ' Grade l5 - SLL!_ '7 i1 i f w_ _ T \ ' “'1 SGO_ __ _ __T 7 Go_ _'T H --4 we “Q As fig as shes as swag BG TJx-d ‘Ox-d uxqq qxfi '- “uoos. uwou 110:0;- 00;. sum-Au oQm-l-u mom-in gQm-lp xgQ-gw xggLw 319.5311»: gap,” 31:00 faced» .3205 32.33, eve; ers= ews= Q» sea éwsfi uésfl eefii §§"" aafifi 55"" §a~“ =‘3§ 41,-: fifi §§ Iflbred Macha Deltapine Rogers Acala VARIETY L/ 19M and 19145 crops only 3/, l9h4_crop only Figure 2. Three-year average for grade of cottons grolwn at College Station and harvested by difierent methods, 1943-1945. a .4) ‘u. __._...t Table 3. Three-year average for commercial classification and fiber measurements for four varieties of ‘cotton grown at two Texas locations and harvested by four different methods, 1943-1945 _ _ _Fiber laboratory test results _ Conimercial Length fibrograph Fineness _ Variety Harvest method classification (weight Mature Fiberl . Upper Uiiiform- per inch fibers tensile Staple half Mean ity of fiber) strength Grade length mean "ratio 32nd _ _ 1000 lb. per inch inch inch Index Micrograms % sq. in. College Station Iii-Bred Hand-picked SLM + 25 69 . 57 82 5 .0 70 80 Hand-snapped LM + 26 72 . 58 80 80 Machine-picked? LM 26 72 . 58 80 82 Machine-stripped LM + 25 + 70 .56 80 80 Maclia Hand-picked? LM + 27 77 .61 79 4.2 66 84 Hand-snapped? GO + 27 76 .59 78 86 Machine-picked3 26 73 . 56 77 90 Machine-stripped? GO + 26 76 . 60 78 84 Deltapine Hand-picked SLM-—— 30 88 . 67 77 4 . 0 71 82 Hand-snapped SGO 29 + 88 . 66 76 83 Machine-picked? GO + 29 + 90 .69 76 » 83 Machine-stripped SGO— 87 . 65 75 84 Rogers Acala Hand-picked? LM + 29 -|- 86 . 65 76 3 .6 74 90 Hand-snapped? SG 1 87 . 66 76 93 Machine-picked? SGO + 30 + 89 . 66 74 92 Machine stripped? S 30 88 . 66 75 94 ' _.__\__...a.._. Ana. ~ "‘~ ‘ ' .~i“... l 3’: E E Z Z 9 Q .33 g m E E’. 3 a a 5 5 i=1 >4 "U i=1 5 E m Z a U! F] z» F] II! O Z ZI Table {i-Continued. Lubbock Hi-Bred Hand-picked 25 + . 76 . 61 81 5 .5 74 76 Hand-snapped SLM 26 76 . 60 80 75 Machine-p1cked3 LM 26 74 .61 82 78 Machine-stripped LM + 27— 76 159 78 78 Macha Hand-picked _ Hand-snapped? LM + 28 .87 .68 78 4.7 66 74 Machine-lucked Machine-stripped? SGO + 29 + 84 .64 76 _ 72 Deltapine Hand-picked SLM 31 98 .74 76 4 1 71 74 Hand-snapped L —- 32-—— 98 . 74 75 74 Mac ine-p1cked3 SGO 32 98 . 76 78 70 Machine-stripped SGO 31 96 . 72 75 71 Rogers Acala Hand-picked? M + 33 1 00 .75 76 3 9 72 84 Hand-snapped2 LM 32 98 . 72 74 84 Machine-plcked?‘ LM 33 95 . 7 1 75 83 Machine-stripped? LM 32 + 94 .70 74 80 lCorrected from Pressley index according to the following formula: zAverage of 1944 and 1945 crops only. 31944 crop only. Tensile strength = (10.8116 x Pressley index) —0. 12 21 NOI-CLOD SNI-LSEIIAHVH JO SGOHJZGIIN JLNEIHEIJJIG JO NIOSIHVJHOO I Table 4. The average manufacturing performance, Shirley Analyzer waste and yarn qualityjor four varieties of cotton grown at two Texas locations and harvested by four dilferent methods, 1943-1945 a l-l uh Waste Skein strength of carded yarns N Yarn appearance?’ eps _ _ _ Third count spunl Equivalent per 100 Third count spunl Varlety Harvest method Shirley Plcker 22s 36s staple sq. 1n. 22s 36s W l Ana- and length? card c: lyzer card 14s 44s 50s 60s web 14s 44s 50s 60s ‘ g % % lbs. lbs. lbs. lbs. lbs. lbs. 32nd inch N0. grade a College State Z Hi-Bred Hand-picked 4 . 6 8 . 7 80 . 1 40.1 129 .6 25—- 1 1 B + B + B + 9 Hand7snapped 5.6 10.1 80.6 41.1 133.0 25 10 B + - B B + s, Machlne-plcked4 6.2 10.8 83 .2 41.8 137 .2 25 + 7 B + B B + $ Machine-stripped 6 . 2 10.3 80. 6 40. 1 131.5 25— 10 B + B B + ' Macha Hand-p1cked4 -— 5.4 9.3 88.8 46 .2 135 .8 34.8 27 22 B + B B + B l-g Hand-snapped4 9 .4 15 .0 90.0 46. 3 142.3 35.5 27 + 28 B C + B + B t1! Machjne-plckedli 14.0 17.1 92. 6 51 . 5 145.3 . - 29 27 B C + B + >4 Machme-stripped4 10 . 2 15. l, 90.0 45.6 142.8 -33 . 2 27 + 24 B C + B + B 7P Deltapine Hand-picked 6 . 3 8 .8 98 . 1 52 .8 37.3 36.2 32— 38 B B C + C + m ' Hand-snapped 10.0 12.0 -98.4 52.3 39.0 32.8 31 29 B C + C + C + p» Machine-plcked4 10.2 13.2 99.6 53.2 40.5 33.5 31 + 36 B C + C + B G! Machine-stripped 12.0 14.5 96.3 51.0 38.3 32.0 31—— 39 B C + C + C + a Rogers Acala Hand-plcked4 4.6 7.4 106.8 57.6 41.8 36.2 33 + 24 B + B B C + Q Hand-snapped4 8.0 10.9 106.8 57 .0 - 35.2 33 + 25 B C + C + C.‘ Machlne-plc_ked4 9.1 12.5 109.0 59 .8 45.1 37. 3 34 + 28 B C + C + C + t" Mach1ne~str1pped4 8 .6 12. 6 106.5 58 .3 44.4 36.3 34 + 39 C + C + C + C + g Lubbock § l?‘ Hi-Bred Hand-picked 3 .0 7.5 81.7 40.8 137.7 25 + 10 B + B + B + [q Hand-snapped 4.6 8.7 84.4 42 2 139.3 26 14 B + B + B + >4 Machine-plcked5 5.0 9 .0 82.2 41 7 134.0 26 4 B + B + . B + '0 Machine-stripped 4.8 9 .3 84.2 41 7 140.0 26 + 12 B + B + - B P! Macha Hand-picked a Hand-snapped4 6.3 14 .0 86 .8 45 0 32.0 28 .6 27 + 25 B C + B C + g Machine-plcked tr] Machine-stripped4 10.2 15 .4 87 . 8 45 .7 33 .8 29.1 27 + 25 B C + C + C + Z Deltapine Hand-picked 5.1 7.7 99. 1 52 . 7 33 . 8 32—- 19 B B C + h] Hand-snapped 6.6 10.1 99.1 51.9 33.8 31+ 20 B C + C + m MflChlIl6—p1Ck8d5 8.5 12.8 93.8 48.3 31.9 30 17 B C + C + g Machine-stripped 10.8 13 .1 98.2 51.5 32.9 31 + 30 B C + C + 11> Rogers Acala Hand-picked4 3.3 5.8 107.6 57.2 27.1 34 20 B C + C + j Hand-snapped4 6 .8 9.4 104.7 55.4 27 .0 33 38 C + C C Q Machine-p1cked5 5 .5 7 . 4 103. 6 55. 1 26. 1 33 24 B C + C + z Machine-stripped‘ 7 . 7 l0 . 2 100. 5 54 . 4 26.5 32 + 46 C + C D + i,‘ m, 4.‘ lFigui-es listed in these columns indicate count spun. . ._.. I“ . ,4 _- W’ f.“ L; -~._év -.__.fl- at“, '-1 u COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 15 grade of cotton, but had little effect on the staple length. The three-year average of the grade for each variety and method of harvesting is shown in Figure 2 for Coflege Stafion and in Figure 3 for Lubbock. Shnflar averages for classers staple length are illustrated in Figure 4 for both Coflege Stafion and Lubbock. The other nufihods of harvesfing for each variety averaged from approximately one to two grades lower than the hand-picked samples at both locations. The various methods of harvesting for each variety averaged within approximately 1/32 inch of each other without any consistent relationship between staple length and method of harvesfing used. Grade i! M ___ 1 sm _ T _ 1 i m\. I i T 5G0 _ GO _ A bi Q11: 11 Q1: Q1: 1:3. q] 3. 1:3. ‘E113. can. m on. r-l wo._ BG ‘UM-r! ‘U w-l ‘UM-H ‘OX-H ‘ 8&3}; 31 f; 88.3.‘; 732L333 xQQ-n Q1 m xQCAm xmtlm 32.1,!» ‘é a, fiéét 328M‘, anus: n 5 awn: 0.11:5: $13212 1‘; e 64/22 1515:? 558° 5 S “$38 $5°8 ::::::=i§' u: :1 pxznfi: rnszg: Hibred. Macha _ Delta ine Ro ers Acala P 8 VARIETY y 19M. and 1916 crops only g/ 191+!» crop only Figure 3. Three-year average for grade of cottons grown at Lubbock and harvested by different methods, 1943-1945. 16 BULLETIN NO. 683, TEXAS AGRICULTURAL EXPERIMENT STATION SPINNING TESTS ‘ Complete spinning tests were made on samples of each variety harvested by the variousmethods for each crop year at College Station and Lubbock. Measurements made in these tests included percentage of ginned lint removed as picker and card waste, neps per 100 square inches of card web, A " skein strength and yarn appearance grades of three counts of yarn, and equivalent staple length. The 1943 and 1944 samples were manufactured by using the conventional or regular draft system. The 1945 samples were manufactured by using the long draft system and the yarn strengths were adjusted to the regular draft level by using the formula worked out’ by the U. S. Department of Agriculture. In addition to the spinning tests, Shirley Analyzer waste tests were made on the 1944 and 1945 samples to determine the amount of foreign matter in the ginned lint. The three- year average of the results obtained is shown in Table 4 according to location, variety, and method of harvesting. The spinning tests show that the most important factor of manufac- turing quality as affected by method of harvesting is the amount of waste‘ I or foreign matter in the ginned lint. The three-year average of the picker and card waste removed for each variety and method of harvesting are illustrated in Figure 5 for College Station and in Figure 6 for Lubbock.‘ 3 The waste for the two locations are on different levels but show the same trends between methods of harvesting. The Shirley Analyzer waste show Staple Length ' 32nd Inches Grown at College Station, Texas Grown at Lubbock, Texas 3:. I I I I 41 as - 3-.’- . . ,__ a1. FT 2o 29 __ W- F I 27_ F- 26- 25_ 2“ m a 23- fie fin H u fir‘; - a a2 m“: a “E 2a m“ 15.3w ‘OX-H ux-rl x- ‘U-H ux-a u I!’ ' M“ aaa“ sax“ a a: sax: 2a i‘??? XILO-fi XCLCL: D4?! XILQI-n XO- m 1U I UNI! UKU'| \ l!!! om- h OI q 5S2 35°” ma" °' 52 “S°§‘=’ ‘AS |.,-q.,4 10.55 ,.,-»-5 -S- l-rl cls-A IL "ass gges 225s e gs ggeg gig o as; =1=as saaq a =§ ==a= II Jeltapine logers cala Hibred Nacha Deltapine ogen VARIETY if égtt gggpigggycrops only‘ 1 %? Figure 4. Three-year average for claesefs staple length of cottons harvested by different a; methods, 1943-1945. '- \ COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 17 i l t Percent _ Equagdzn 17 _ T a a l6 - 1s _ __ -. , “'7 v 11,; _.>oo, l3 _ "- __.-a l2 _ __ u; ll _ _ 1o _ _ ‘- 9 . T _ "Sm 8 _ _Ll 7 ‘ '_ -$M .GM 6 _ \ \' \¢-| a _ 5m ~11 hi1! w?‘ - 3% abet 2% when - 158%? e"€”¢1 e°€€ u“€'€ gas: stat stat stag ‘Big 615;; 641:}. uwialck: ?=~~ ==°~ 55:: sax: 0 §§§§ §E§§§| nzlzcs: x222 * Hibred Macha Deltapine Roger's Acala. VARIETY y 191,1, and l9l+5 crops only g/ 19M, crop only Figure 5. Three-year average of picker and card waste removed from cottons grown at College Station and harvested by diiferent methods, 1943-1945. the same general relationship as do picker and card waste. The differences between the waste removed from the hand-picked samples and those harvested by the various other methods are relatively small for the short, coarse-fibered cottons. In the case of the longer and finer cottons, how- ever, the hand-snapped, lmachine-picked, and machine-stripped samples show a larger increase in waste as compared with the hand-picked cottons. These results are in line with popular opinion concerning the cleanability of short, coarse-fibered cottons. The increase in the waste for the hand-snapped and machine harvested samples as compared with the hand-picked samples is quite significant, especially for the longer staple cottons, and would be objectionable in manufacturing even though it is largely removable. The use of such -cotton in a manufacturing ‘plant, in addition to the extra Waste loss, 18 BULLETIN NO. 683, TEXAS AGRICULTURAL EXPERIMENT STATION would put an extra burden on the cleaning machinery and would probably 5 necessitate the installation of additional cleaning equipment, as well as creating undesirable working conditions owing to excessive impurities in a the air. The most significant item in these data is the fact that only relatively small differences occurred in waster content between the hand-snapped samples and the machine-harvested samples on the short staple cottons. As hand-snapping is generally considered the standard harvesting method f for the Plains. area of Texas and shorter staple cotton is widely grown, there should be little objection to machine harvesting in that area. Quality measurements of the yarns show the same trends for the various _3 counts spun. The three-year average of skein strength of 22_s yarn to- ‘ gether with its equivalent staple length for each variety and method of percent Equivalent l7 Grade r60 16 - I 15 _ T 11+ - ._ -soo 13 _ _ It“ 12 _ m ll __ l0 _ ._ -— -— SLII 9 - J‘ - a _ T _" 7 _ _' -" _su 6 ,Gll - m a " firs 1: he @u ' “a A g". 8% Hmgg -, egg? u -.-a 11x i 1,11%}: "éfififi 3 f3 "$8.3 p vita.» x mo.» n. m x 0.0. v» x o. on 336$ 2 i» 32$ J, 3'8 68> was *2 ,5. 92255 ‘ma; 1115:: g .1: 11-85 g no.5” 5508' n! U gain! <0 55mm 0 :::::§::i n: § macs 2 azzczi: Hibred Macha Deltapine Rogers Acala VARIETY 1/ 19M; and 191-6 crops only 2/ 191A crop only Figure 6. Three-year average of picker and card waste removed from cottons grown a! l? Lubbock and harvested by difierent methods, 1943-1945. m‘ COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 19 Pounds Tiquivalcnt Staple - 32ndinchesg/ 1 -36 i ' T- > -35 __' -31; _?-3 _, T) _ -31 ._ -312 2f! _¢2 ..‘7 :26 _J_. .__ _ H \ a a ‘fig ‘H13 Hg ‘Hg r-{UCL pa. r-l ‘SQ m mo. 0c. D wax-a vac-a ‘OX-g vxa 1:41:03. noon 1:00 woo» mil-HP QQ<'I'(~4J OCL-v-l-o-i wQ-a.) xQCLv) xQ-fhrn .2409‘!!! XL-sflum o |. on l or: '\ 0.110 Agoo q-qcoo "-4200 q-acoo ‘Fwgfi “"955 “P55 9'95“ 1- - o \ ' ' 11-52,: -<';'a.c.c: uwxlr v-ozl: 553° S533 5&3? $533 mum-Q 22:42: fizz: main; Hibred lhcha Deltapine Rogers Lcala VARIETY y 19M; and 1916 crops only g/ 191th crop only » _ 3/ The equivalent sts-ple length is tho staple length generally‘ required to Btoduce the y: rn strength obtained. _ re 7. Three-year average for skein strength of 22’s yarn from cottons grown at College Station and harvested by different methods, 1943-1945. 1 esting are illustrated in Figure 7 for College Station and in Figure‘ lfor Lubbock. There were large differences in yarn strength between rieties but little difference could be attributed to the harvestiiig- method Iployed. The yarns from machine-picked cottons, however, had a tend- » cy to be slightly stronger than the yarns from cottons harvested by the her methods. ' . __Yarn appearance, in addition- to yarn strength, is an important item Q evaluating the quality of yarn produced from a cotton. The yarn pearance for 22s yarns for each variety and method of harvesting for 20 BULLETIN NO. 683, TEXAS AGRICULTURAL EXPERIMENT STATION the three-year period is illustrated in Figure 9 for both College Station and Lubbock. Since most of the foreign matter is removed from cotton . . HAJGLI$ i in preparatory cleaning processes before it reaches the spinning operation, 5 it is logical that little damage is done to the yarn appearance due to pf method of harvesting. The appearance grades did, however, show a tend- ency to drop slightly for the roughly harvested cottons, especially for . the longer staples. Pfiuflds 32nd Inches g _3 113 _ ' - _ >35 e i1 '3" . t T 11 100 ; __1 _32 ' "1 j -3l ' — -30 9O _ -39 "" -28 ‘T - ,2? __, ._ 8O 1 -- _26 ' ~ 25 7o _ - W R as 2 Es he no. R1 c. us. [mm-cg 50 113-5 e 3‘ e53 19H _ 3 S“ ‘B. "‘ “Ei-S“ BE-Sf; -. x ab; o: ‘w’: gnarl; xcnm fifilinl» ‘E 32033, SEJML ?"|"5|-§ ‘f’ .5 FTWEE 9535.5 11114:: -o 4: nos: 12151:: 55 33' g 3:’ 553$ $55353 0 :1: s2 :1: 2 2:222 ::::1::s2 Hlbred Macha Deltapine Rogers Acala VARIETY 2/ The equivalent staple length is the stilPle ‘length generally required b0 Prmiuce the yarn strength obtained. _]_,/ 19bit and l9h5 crops only g/ 19M crop only Figure 8. Three-year average for skein strength of 22's yarn from cottons grown at Lubbock , and harvested by difierent methods, 1943-1945. Equivalent Staple COMPARISON OF DIFFERENT METHODS OF HARVESTING COTTON 21 G d Grown at College Station, Texas ' Grown at Lubbock, Texas rae A | I | W *< A- B-v. _, —- B‘ —_ _'_l — 7 c“ __ _ C. 13+- v- > -| a W ‘ fig N3 5g “g m}? q? El? ‘hi’: m. gg gmgg 3% has as s as s~sa 1,73%: 218%: wait 113%? v-gfif 158%? 11.3%": ass: 2223a: sass ass: sea: as gfigzs? E??? " g I| u l’ oqs-- umn- o~|' m! _~oo _"f1__w0 _ ~4§u>oa1gw° wcoo q-(CUQ q-aggg 5Q agck. m; l ~55 6,552 ‘P955 $13515 34,22 .55 ages 13,5553 1112100 U0 0'00‘) ‘UTZOU C QQ c, p500 give 5;; Eias Eéaa Essa rise as sass s»ss - Hibred Macha Deltapine Rogers l Hibred Macha Deltapine Rogers > O l1! l? > O f“ k4 W y 19M and 1916 crops only _2/ 191,1. crop only Figure 9. Three-year average for appearance of 22's yarn from cottons harvested by difierent methods, 1943-1945. SUMMARY AND CONCLUSIONS Data presented in ‘this bulletin were collected during the three-year period, 1943-1945, inclusive, on four varieties of cotton grown at two locations, College Station and Lubbock. Each variety .was harvested by four methods when adequate equipment was available. The four methods of harvesting the cottons were the commonly practiced methods: hand- picking, hand-snapping, machine-stripping‘ and machine picking. Four varieties of cotton differing widely in their fiber properties were selected for the study: Hi-Bred because of its coarse, short staple, Macha because of its stormproof qualities, Deltapine because of its medium staple length, and Rogers Acala because of its longer staple and better spinning quality. All samples were cleaned and ginned by the U. S. Cotton Field Station at Stoneville, Mississippi, and the fiber and spinning tests were made by the U. S. Cotton Testing Laboratory at College Station. Data on the percentage of burs and Waste removed from hand-snapped and machine-stripped cotton did not show a significant difference. There was an apparent significant difference, however, in the percentage of burs and waste removed when varieties are compared. The highest percentage of motes and waste removedyfrom the cotton in cleaning and ginning was found in samples from the machine-picked method of harvest. This cotton had not been run through an extractor ‘affected by the method of harvest. The hand-picked cottons averaged one 22 BULLETIN NO. 683. TEXAS AGRICULTURAL EXPERIMENT STATION prior to- ginning as was the case with the hand-snapped and machine-p’: stripped cotton. “i More motes and waste were removed from the Hi-Bred, short stapleflf. hand-picked samples than were removed from the rougher methods harvesting—hand-snapping and machine-stripping. The results were ire- i‘ versed for the stormproof‘ and longer staple varieties, Macha, Deltapine‘ i and RogersAcala. o - Fiber properties and classers staple length were not appreciably affected by the method of harvest. The grade, however, was very significantly to two grades higher than the other methods of harvesting. pSpinning tests showthat the most important factor of manufacturing quality as affected by method of harvesting was that of the amount of waste or foreign matter in the lint. The increase in picker and card Waste for roughly harvested cotton as compared with hand-picked cotton was significant, especially for the longer staple cottons. ' Relatively small differences were found in picker and card waste content p _ between the hand-snapped samples and the machine-harvested samples of w, the short staple cottons. I" Method of harvesting had little effect on the quality of the yarn manu- ‘l, facturedexcept for a slight lowering of the appearance grade for the f longer and finer fibered cottons. - i ACKNOWLEDGMENTS The authors wish to express their appreciation to W. E. McCune for his. assistance in collecting data in these studies; to the U. S. Cotton Field Station, Stoneville, Mississippi, for cleaning and ginning of the samples of cottons; to the International Harvester Company for assistance in harvesting the machine-picked samples; and to all others who rendered assistance in connection with these studies.