ethridge, d., j. brown, j. price, c.k. bragg. bark in

Reprinted from Proceedings of the Beltwide Cotton Conference

(1992):1223-1226.

Ethridge, D., J. Brown, J. Price, C.K. Bragg. "Bark in

Cotton Lint: Effects on Processing Costs." Beltwide

Cotton Conference, (1992): 1223-1226.

BARK IN COTTON LINT: EFFECTS ON PROCESSING COSTS Don Ethridge, Jeff Brown, John Price, and C. K. Bragg

Professor and Research Assistant, Department of ~gricult~ral Economics, Texas Tech University;

AssIstant DIrector, International Center for Textile Research and Developm.ent, Texas Tech University, Lubbock, TX; and TextIle Technologist, USDA, ARS,

Clemson, SC

Abstract

Textile processing results using cotton with different levels of bark from four different textile processing perfor~ance studies were analyzed individually to determIne the effects of bark in cotton on textile processing. The results indicate that cotton reduced one grade due to bark content added little to processing costs with rotor spinning. However, cotton reduced two grades. because of ~ark added somewhat more to processing cost WIth rotor spInning, but had a substantial effect on processing cost with ring spinning. Aggressive cleaning of cotton can reduce processing efficiency losses (costs), but it adds to waste losses. Results suggest that the one or two grade reduction for bark often results in cotton receiving discounts under the CCC loan schedule greater than justified by processing losses.

Introduction

The existence of bark, i.e., pieces of woody material from the stalk and/or branches of the cotton plant, in cotton lint and the costs incurred by its presence affect all segments of the cotton industry. Bark in cotton causes problems for textile mills in various processing stages and/or it may result in impurities or defects in the yarn and fabric, which affects its value to consumers. Therefore, the bark tends to increase production processing costs and/or decrease the value of the product. Consequently, bark in cotton represents a lower price (greater discount) to the cotton producer.

Classing of cotton is a procedure which evaluates quality attributes of the cotton fiber; each bale is classed. The market assigns prices to cotton of various quality combinations, which facilitates the marketing and production of cotton. The official classing of cotton, conducted by the Agricultural Marketing Service of the United States Department of Agriculture currently includes six quality attributes of the cotton lint: trash content, color, fiber length, micronaire, strength, and length uniformity. Two attributes, those being trash content and color, are encompassed in the grade. One component of trash content is bark. Under classing rules, the presence of bark in cotton resul ts in the cotton being lowered one or two grades (e.g., grade 42 to grade 52 or grade 62), depending on the severity of the bark content. To the extent that bark presents a problem which is different from the damage inflicted by other types of foreign material, this rule imposes a bark discount on the cotton which may be arbitrary. One problem is that the degree to which this loss in value to a producer is related to the decrease in the use value of the cotton to the processor is not known. If the marketing system is effective, the processing losses should be approximately the same as the producer discounts (with the possibility of short-run aberrations from market dislocations) .

Bark in cotton is not a new problem for the industry, but concern about it has increased with the industry's growing emphasis on quality fiber. All regions of the country have a problem with bark to some degree; however, the problem is most severe in the Southwest Region where cotton is predominantly machine stripped . Between 1967 and 1984, approximately 30% of the total bales harvested in the Southwest Region were reduced in grade due to bark. This compares to less than 5% in the other regions where cotton is predominantly machine picked (Ethridge and Neeper, 1986). In upland cotton, bark makes up aore than 50\ of the grade reductions associated with trash content in the United States (Anderson, 1991).

Even though the existence of bark in cotton can be related to stripper harvesting, the environment. cu1 tura1 practices, seed variety, other harvesting practices, and o ther factors influence the degree to which bark occurs. However, these i n fluences are not well understOOd, thereby making it difficult to correct for these problems. It may be noted however, that research done by Brashears (1984, 1985) o n harvester modifications has

Cotton Textile Processing 1223

been shown to reduce bark accumulation in the harvested cotton (Supak, 1989).

Bark in cotton causes three general problems tor textile mills. FIrst, bark in cotton increases waste loss in the initial cleaning of cotton in opening and carding. When bark is cleaned tram the cotton 1 int cotton fibers attached to bark, as wel l as bark itself' are lost. This decrease in total weight of cotton, tro~ the loss of lint and bark during cleaning, is a los. in weight of cotton which was paid for. Second, bark that escapes the cleaning process may reduce spinning efficiency by increasing breaks in the yarn (i.e., ends down). Breaks in the yarn during spinning muat be restarted, thereby increasing manufacturing cost s. Third, bark can cause defects in the yarn and ultiaately the fabric. Defects in the fabric are unappealing to consumers, and thus reduces the value of the yarn, fabric, or garment.

Given that the losses to textile processors lroa bark in cotton--the loss in use value--should be related to the loss in market value of cotton tiber which contains bark, it is important to understand, and hopefully quantify, the costs from bark in textile processing. Therefore, the objectives of this study were to: 1) estimate the costs of various levels at bark in textile processing of cotton, and 2) relate the.e cost. back to the discounts for bark in the grading and pricing sYBte • . Achieving these objectives should provide Bomo insights on reasonable expected levels of market price discounts for bark.

Methods And Prgcedures

The method of estimating the cost of processing cotton with varying levels of bark was divided into two stages: total waste loss during opening and csrding and breaks in the yarn during spinning. Opening and csrding cotton is the stage where the cotton lint is sepsrated, cleaned, and al igned. Host of the foreign material is removed from the cotton, but so.e amount of lint i. also removed with the bark. The weight ot the foreign material and cotton lint removed (Le., total waste loss) wa. included in the cost of the bale of cotton. Theretore, tho increase in total waste loss from cotton with no bark to cotton with bark was estimated, then a value (coat) was estimated for the waste loss caused by the bark.

In the spinning stage of processing, broaks in the yarn tend to increase with the amount of bark pre.ent in the cotton. There are two general types of .pinning .achines currently being used, rotor spinning machines and ring spinning aachines. The rotor .pinning machine uses centrifugal force and air to twist the cotton lint into yarn and wind it on spools. The ring spinning machine uses more moving parts and causes increased fr iction between the cotton lint and the machine aa yarn is pulled, twisted, and wound onto spools. Therefore, when breaks occur using either machine there is a cost involved in repairing it. Thus, the increa.e in breaks from cotton with no bark to cotton containing bark wa s estimated, then the increased cost troD this 108a i n processing (spinning ) efficiency was e.tJaated.

The waste loss and processing efficiency data tor this analysis were frail five separate texti le processing perfonaance stud ies. One study, referrod to as the "Price 1991 Study" (Price, 1991), provided tiber measurements and spinning tests on a .ample at 16 bales of cotton, 12 of thel'l des ignated as having sutticient bark to be reduced one grade due to excess bark, and four of them not reduced ( not barky). The cotton used in that study had fiber properties which varied only slightly in micronaire and grade. The textile cleaning equipment. used in that study was a modern single card machine, and the yarn was produced by rotor spinning. The spinning was conducted at a spindle speed of 90,000 rplll at a twist multiplier of 4.0 to produce a yarn count of 26.

The "Price and Shaw Study" (Price and Shaw, 1988) provided fiber lIIeasureJllents and spinning tests on a

1992 8tll\o\ide Collon Con(er .. nc~'i

sample of 18 lots of cotton with each lot consisting of three bales of cotton. six of the lots were designated as having no bark content, where each bale ha? not been reduced in grade, six of the lots were des1gnated as having medium bark content, where each bale had been reduced one grade due to bark, and six of the lots were designated as having heavy bark content, where each bale had been reduced one or two grades due to bark. Three of the lots having heavy bark content were tested under different textile processing conditions than the rest of the sample and were deleted from this analysis. The fiber properties of cotton in the Price and Shaw Study were nominally the same, yet differing somewhat, in micronaire, grade, and bark content. Th,e clean.lng equipment used in that study was an older slngle card, and both rotor and ring spinning were used to spin the yarn. The rotor spinni ng was conducted at a spindle speed of 90 , 000 rpm at a twist multiplier of 4.0 to produce a yarn count of 26. The ring spinning was conducted at a spindle speed of 11,000 rpm at a twist multiplier of 3.81 to produce a yarn count of 26. The third processing study, the IIPrice 1992 Study II (Price 1992), used the same cottons and processing conditions, but added two new conditions to the "old II single carding in the Price and Shaw Study. The new conditions were modern single carding and tandem carding.

The fourth study, the "Bragg et al. study" (Bragg et a1., 1991a) provided fiber measurements and spinning tests on a sample of five different mixes of cotton . Two samples of cotton, one having low bark content graded Middling and the other having high bark content graded Strict Low Middling, were blended to make the five mixes of cotton . The mixes were 100\ low bark content for mix 1, 75\ low bark and 25t high bark for mix 2, 50t low and 50\ high bark for mix 3, 25t low and 75\ high bark for mix 4, and 100\ high bark (reduced one grade because of bark) for mix 5. All other fiber properties of the cotton used in that study were consistent . The cleaning equipment used in that study was (a) standard ("old " ) cleaning a nd carding, (b) standard cleaning, tandem carding , and (c) modern ( "state of the art") cleaning and carding. The yarn was spun on a rotor spinning machine. The spinning was conducted at a spindle speed of 100,000 rpm at a twist multiplier average of 3.75 to produce a yarn count of 30 . A fifth study (Bragg et al., 1991b) was also analyzed, but the results are not reported here because the results are duplicated in the more comprehensive stUdy (Bragg et al., 1991a).

The methods of estimating both waste loss costs and processing efficiency costs were similar across all five of the prior studies . The procedure for establishing waste losses was to examine waste losses as:

W - ftC,) where W - waste loss (\ of weight of cotton),

C~ - non-lint content (t of weight of cotton,

and C" ,. g(B) where B - bark level (this measure varied with the different processing studies; it will be further explained). In any event, waste is dependent on the bark level,

W ." h(B), either indirectly tnrough the above relationships or directly by bypassing the interim relationship.

The processing efficiency, measured by the break rate in the spinning process, was evaluated similarly:

F - j(C,)

where F - break rate (breaks per spindle hour). Given that C~ ,. g(B), then F = m(B). In one instance, break rate was determined from the level of waste (Price and Shaw).

In order to determine the economic losses associated with the weight losses, cotton prices were needed to establish the dollar value of a weight loss. Further, to put the processing cost losses in terms of producer prices, an adjustment was needed to account for the cost of moving the cotton, including the bark and wasted cotton (the waste loss), from farm to mill. Rather than calculate the various costs for transportation, insurance, handling. etc., and aggregate them, the simpler approach of estimating the margin was used. The margin, or difference between the price paid by processing firms and the price received by farmers,


represents all costs between the two points. The farm price of cotton was calculated to be the average of all designated spot market prices for the years 1983 through 1988 for grades 31 and 41, staple 34, 3.5 through 4.9 micronaire (U.S . Department of Agriculture, 1989). The mill price of cotton was calculated as group 201 mill point prices for the same period and the same qualities (U.s. Department of Agriculture, 1989). The average marketing cost (margin) was estimated in this way to be 8.31 cents/lb.

The cost of a break in the yarn was used to quantify the increased cost of spinning yarn from cotton containing bark. The break cost data were provided by Schlafhorst, Inc. (Deussen, 1991). Deussen estimated the manufacturing cost per pound, production per machine per hour, and breaks per machine per hour for varying break rates . By taking the change in manufacturing cost times the production pounds per machine per hour divided by the breaks per machine per hour, he arrived at a cost per break. Deussen estimated the manufacturing costs, including all labor, capital, and operating costs, in the spinning room (excluding raw materials cost, overhead, and profit) for each break in rotor and ring spinning to be 0 . 6 cents and 3.0 cents, respectively.

The cost of bark in cotton beyond spinning, e.g., in finishing, dyeing, etc., were not quantified in this study. Information to establish any potential loss in value associated with any defects or additional weight losses was not available. Also, the waste accumulated during cleaning has some salable or reusable value to textile mills; however, these economic returns were likewise not accounted for in this study.

To estimate the loss in value due to total waste loss in cotton, which is justified by a decrease in its value to the textile processor, the change in total waste loss from each bark designation for a selected producer price provides that estimate. This relationship can be specified as:

WC - AW(P + He) where we = cost of bark to the textile processor in

cents/lb. of cotton due to waste loss, lJ. symbol for "change in, II W total (opening and carding) waste loss

expressed as a percentage of weight of cotton,

P producer price of cotton in cents/lb., HC marketing cost in cents/lb. = $ 0.0831.

In the analysis, the producer prices of cotton selected were in five cents per pound increments from 50 to 75 cents per pound. This same approach for calculating waste cost was used for all the processing studies.

The other processing problem attributable to bark was the increased number of breaks. Once the break rate per spindle hour was estimated, this value was converted to breaks per pound of clean cotton processed per spindle hour. The following formul.a provides the estimated pounds of clean cotton processed per spindle hour.

where PP = (R * H) / (504 * y' .5 * T)

PP = pounds of clean cotton processed per spindle hour,

R = spi.ndle speed in revolutions per minute (rpm), H = sp1ndle hours, Y yarn count = number of hanks of 840 yards

which weigh one pound, T twist multiplier - turns per inch per square

root of yarn count.

To estimate the cost of breaks in spinn ing to raw cotton, Le., the form in which producers sell the cotton, the amount of clean cotton processed per spindle hour had to be divided by the total waste loss percentage to get the cotton back to a raw pounds estimate. That calculation is encompassed in the formula to estimate the break cost per pound. To determine the cost of bark i n cotton attributable to breaks in the different bark designated cotton,

where, Be o

F

BC = (D . AF) / [PP / (1 - W» break cost, in cents per pound of cotton, cost of one break for designated type of spinning, in cents per break, spinning break rate per spindle hour.

To determine the full loss in value attributable to the different levels of bark in the cotton in each of the studies, the two costs, i.e., the waste cost (WC) and

1992 Beltwide Cotton Conferences

break cost (BC), were summed to obtain the textile processing costs attributable to varying levels of bark in cotton:

TC "" WC + Be where TC = total cost of bark attributable to each bark content designation.

Results

The results of this analysis provide an estimate of the loss in use value (costs) to textile processors for processing cotton wi th var~ous bark designations on different types of processing equipment. In the Price 1991 Study, where the distinction was made only between barky and non-barky cotton and the bark levels were the highest of all the studies (3.38 to 12.87% non-lint content) , the waste loss between the two bark designations was greatest (Table 1). The Price and Shaw ~nd Price 1992 Studies showed no significant difference ~n waste loss between non-barky cotton and .tmedium" bark cotton. The bark levels in those cottons was the second high~st (2.34 to 6.28% non-lint content) among the stud~es. Note that the waste loss increased as the carding technology improved/ increased. cottons in the Bragg et al. study had the lowest levels, and the narrowest range, of bark (3.62 to 4.66% non-lint content) . That is, the .theavy bark" (Mix 5) in that study had substantially less bark than in the other two/three ~tudies. Consequently, the waste losses were correspond~ngly lower. Note also that waste loss increases as cleaning and carding technology increase. Generally, the modern cleaning and carding equipment is more thorough in removing the bark and thus the waste loss is greater. The cost of waste loss is larger with the more mo?ern equipment. However waste losses appear to be relat1vely small (well below 1%) until bark content approaches a level which warrants a two-grade reduction in the classing system.

The resulting losses in use value due to losses in spinning efficiency complement the waste cost results. In the Price 1001 study there was no significant loss in spinning efficiency (Table 2). The modern cleaning equipment used in that study effectively left no bark in the cotton to cause spinning efficiency losses.

In the Price and Shaw and Price 1992 studies, the cottons showed no spinning efficiency losses up to medium bark levels with either rotor or ring spinning. Break rates between medium and heavy bark increased with both rotor and ring spinning. The break rates increased substantially (70-100%) with tlo1d" single carding. The relative increase was less with the more advanced carding with rotor spinning but carding had little effect on the relative increase in break rates with ring spinning. While break rates are much lower with ring than rotor spinning , recall that the cost of a break is much higher with ring spinning.

In the Bragg et al. Study, results were consistent with those above, given the differences in initial bark content of the cottons (Table 2). Break rates increased as bark increased, but the degree varied with the cleaning technology. The break rate increased most as bark increased, and break rates were consistently higher, with the standard textile processing system. The most modern system had an intermediate number of breaks, but the initial level of bark in the cotton had no effect on break rate; the modern equipment cleans cotton so well that it all spins about the same. The lowest break rates were with standard cleaning and tandem carding, but the break rates still increased as the initial level of cotton bark increased.

The total added textile processing cost was relatively consistent across processing studies considering the differences in initial bark levels (Table 3) . With rotor spinning, total processing losses are small (less than 1 cent per pound of cotton) except when the levels of bark contamination become heavy--approaching a 2-grade reduction. The Price and Shaw and Price 1992 data suggest that when bark levels are heavy, more agressive carding combined with modern cleaning causes losses to increase--the spinning efficiency increases are more than offset by increased waste losses. On the other hand, when cotton is relatively clean to begin with, such as in the Bragg et al. study, losses are lowest with standard cleaning and tandem carding. The data suggest that modern cleaning increases waste loss without a


corresponding increase in processing efficiency, but processing losses with standard cleaning are relatively high.

Although results on ring spinning are more limited than those for rotor spinning, this evidence indicates that although moderate bark causes little problem in ring sp~nn~ng, heavy bark is a costly problem . The ring sp1nn~ng losses from bark appear to be in the 6-7.5 cent/ lb. range with costs increasing as cleaning and carding technology increases.

Conclusions

The results of this study show a wide range of added textile processing costs for various bark content cotto~s. Costs are affected by differences in type of clean1ng and carding equipment and spinning technology as well as bark content of cotton. Cotton reduced one grade an~ ,cleaned on modern cleaning equipment seems to eluHnate many of the problems caused by bark in the spinning process. However, the greater total waste loss from more effective cleaning offsets the spinning efficiency loss in many instances. Overall, bark losses in textile processing are small except when bark contamination is heavy.

The evidence on losses incurred from bark in ring spinning versus rotor spinning examined in this study is li~it~d, but it suggests that losses from bark in ring spl.nn~ng processes are substantially greater than in rotor spinning, at least when bark contamination is heavy.

When these results are compared to cotton price differentials in the CCC loan schedule, they suggest that the price penal ties imposed by the classing rules of reducing cotton one or two grades for bark are greater than warranted by the reduction in value to textile processors. This conclusion is based on comparing the processing costs associated with bark with CCC loan schedules for cotton . Although the Daily Spot Cotton Quotations sometimes show much smaller penalties for a grade reduction, such as has often been the case in the Lubbock market in recent weeks, those penal ties still exceed the losses estimated from these processing studies. The scenario of heavy bark with ring spinning come closest to matching the price penalties of a 2-grade reduction.

Acknowledgements

The authors thank Carolyn Simpson, Helmut Oeussen, and Carlos Engels for their assistance with this research. This research was supported by the Plains Cotton Improvement Program and the Committee for Cotton Research Inc.

RefArgnces

1. Anderson, C.G. 1991. Texas upland cotton grade reductions by causes and summary of discounts, 1980-1989 crops. Dept. of Agr. Econ., Tex. Agr. Extension Serv., Texas A , H Univ.

2. Bragg, C.R., C.L. Simpson, A.D. Brashears, and R.V. Baker. 1991a . Effect of bark on spinning efficiency of cotton . paper no. 911502, presented at the American society of Agricultural Engineers meeting, Dec. 17-20, 1991, Chicago, IL.

3. Bragg, C.R., C.L. Simpson, A.D. Brashears, and R.V. Baker. 1991. The effect of bark concentrations on processing efficiency in rotor spinning. 1991 Reltwide Cottoo Conferences Proceedings, Cotton Engineering and Cotton Ginning Conferences, Natl. Cotton Council, pp. 986-989.

4. Brashears, A. 1984. F. Y. 1984 annual report of foreign matter reduction in stripper harvested cotton. USDA/ARS, Lubbock, TX (unpublished manuscript).

5. Brashears, A. 1985 F. Y. 1985 annual report of foreign matter reduction io stripper harvested cotton. USDA/ ARS, Lubbock, TX (unpublished manuscript).

6. Deussen, H. Schlafhorst, Inc., Charlotte, NC., August 9, 1991 (personal communication).


7. Ethridge, D.E. and J. Neeper. 1986. Estimated losses from bark in cotton lint, Texas High Plains. ~ Beltwide cotton Research Conferences Proceedings, Cotton Economics and Marketing conference, Natl. Cotton Council, pp. 305-308.

8. price, J.B. 1991. The effect of bark content on processing performance. Internatl. center for Textile Research and Development, Texas Tech univ., Jan. 22.

9. Price, John B. 1992. The influence of textile cleaning machinery on the processing performance of barky cotton. 1992 Beltwide cotton conferences Proceedings, cotton Textile Processing Conference, National Cotton Council (forthcoming).

Tabla 1. su ... ~ or Wa.ta LO •••• (aa t ot tot.l .. eiql'lt) in S.lectad Situ.tiona

Situ.tlon S.rk o.siqn.tion.

Pric. 1991 Study W.at. lo.a It) ClUInq. In .. a.t. loaa ( t )

Prica and Sh .... nd Pric. 1992

2.U3

JA.dL 10.121

Studi.. ~ MMlIv. BArk "!IVY BArk Ifitb. old sinql. c.rdinq:

w.at. loaa 1\) 4.40 4.40 5.12 Chanq. In .... t. 1_. (t I 0.00 0.72

with .od.rn alnql. cardinq: W.ata lo-a It I 6.84 6.a4 7.12 0.1'19. In ... ata 1oaa,') 0.00 0.a9

witll t.nd •• c.rdinq: w •• t. loa. "I 9.16 9.16 10.41 Cllanq. In .. ,.t. loaa 1\)

ara99 .t al. Study Std. cla.ninq, atd. cardlnq:

w.at. 10 •• ( t) Ch.nq. in .... t. lo.a I t)

Std. claanlnq. t.nd •• c.rdinq: ",.at. 10 •• I t) Ch.nq. in .... t. loa.,t)

lIOd.rn cl.,n!nq. aod.rn c.rdinq, at.-t. 10 •• et) ctlanq, in .... t. 10 •• ( t)

Situ.tion

fr l ce It" 'l"utlv '

Type or 'pinninq hrk d.siqn.t!on Av.r.q. br.ak rat. Ch.nq. in ''''9. br •• k r.ta

Ptlce , Sbl., ,M prlca U'i studl .. :

5.65

7. l2

0.00 1.32

5.07 5 .29 0.2l 0.45 0.61

5.66 0.01 0.01 0.01

7.54 7.77 0 .22 0.45 0.67

Bark o..iqn.tion.

""-"'<t 0.12

Rptor SP' nn' M

0 . 00

S.51 S.74 0.90

5.61 0.02

7.99 ,1.22 0.90

o.n 0.12

Rptor SpinnIng Ring Spinning Type or apinn!nq a.rk d •• lqn,tlon ....1ua-. twU.Ja.... ...lI..HxL ...b.r.O- bllwL. ..lIU.'Cl

Old .lnql. c.rd: Av.r.qa braak r.t. Chanq. in .vq. br •• k r.ta

"odarn alnqla card: Av.r.q. br.ak r.t. Ctlanqa in .vq. braak rat.

Tand •• c.rd: Av.raqa br •• k rat. Chanqa in avq. br •• k rata

DrAgg .t.1 Study : Type or .piN'linq a.rk d.s1qn.Uon

Std. claaninq. a td . c.rd inq: Av.r.q. braak rat. Ch.anqa In .vq. braak r.t.

0.69 0.69 l.l0 0.09 0.09 0.18 0 . 00 0.51 0.00 0 . 09

0.43 o.n 0.56 0.01 0.01 0.11 0.00 O.ll 0.00 0.09

1>.25 0.25 0.l9 0.08 0.01 0.11 0.00 0.14 0.00 0.09

Rqtor Spinn i ng

0.29 O.ll 0.]7 0.40 0.44 0.04 0.07 0 . 11 0.14

Std.. cl a.nlnq, tanda. c .rdlnq: A .... r.q. braak r.t. 0.0' 0.10 0.11 0.12 O.ll ClIanq. 11'1 .vq. braak rat. 0.01 0.02 0.04 O.OS

Mod.rn cl.anlnq • .ad.m c .rdinq: Avar.qa bra.k rata 0.125 0.125 0.125 0.125 0.125 Chanqa in avq. br.ak rata o 00 0.00 0.00 0.00

Cotton Textile Processing

10. Price, J.B. and D.L. Shaw. 1988. A comparison of the spinning performance of cotton containing various levels of bark. Internatl. Center for Textile Research and Development, Texas Tech Univ., Dec. 16.

11. Supak, J.R. 1989. Harvesting practices to reduce bark. 1989 Beltwide cotton Production conferences Proceedings, Natl. Cotton Council, pp. 614-615.

12. U.S. Department of Agriculture. 1989. cotton price statistics, 1988-89." Agricultural Marketing Service, Cotton Division, Memphis, TN. Vol. 70, No. 13, Aug., p. 17.

1226

Tabl. l. Added Taxtila Proc.a.inq co.t., in Cane. per PoWld or Producara' Cotton, ,usoci.ted .. ith hrk in Cotton

Pric' St.udy Producar Rotor cot ton :iJU.nning prlC' Hut

SO 1.27

" 1.45

" " 1.66

" 1. 77

Pr'c • 91" .Insl. CU"

H.,vy berk

Rotor R'ns

• SbIW/prICI 1,,2 Stud' .. """ern .'ngl, C,rd Tnn"" Cit"

MA.n boO "",VY Nr" Rotor Rips Rotor plno

canta lib. ----- ---------------------------

0.66 6.14

0.70 6.17

0.71 6.!iI1

0.77 6.95

0.80 6.9'

0.14 7 . 02

0.76 6.9l

0.'0 6.98

0.84 7.02

0.19 7.07

0.93 7.11

0." 7.16

RF...... .1 Sfeurl" Rotor ,pinning

L01 7.18

1.07 7.25

1.14 7.32

t.n 7.l8

l.a7 7.45

1.34

:sr.d cleAn at" CII]' St" CI.no raw cerd MOO Clfln wgd Cfn! IU..L.2 a.i.Ll !UJLi tI..L.L..1 IS1L2 I:U.Ll IWL..J. tlU..J .IU.L..l. IliL.l. IWL..J. WJ

------------------------------------- cant·/lb. ----------------------------

50 0.20 0.39 O.St 0.7' 0.02 0.05 0.01 0.10 0.12 0.23 0.l5 0.46

55 0.21 0. 41 0.62 0.83 0.02 0.05 0.07 0.10 O.ll 0.25 0.l8 0 .51

60 0.22 0.44 0.66 0.87 0.02 0.05 0 . 07 0.10 0.14 0.28 0.42 0 .55

liS 0.2l 0.46 0.69 0.92 0.02 0.05 0.07 0 .10 0.15 0.30 0.45 0.60

70 0.24 0.48 0.72 0.96 0.02 O.OS 0.07 0.10 0.16 0.32 0.41 0.64

75 0.25 0.50 0.76 1.01 0.02 0.05 0.07 0.10 0.17 0.34 0.52 0.69


ethridge, d., j. brown, j. price, c.k. bragg. bark in

Documents