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ADVANCES

IN

AGRONOMY

VOLUME

II



ADVANCES

IN

AGRONOMY
Prepared under the Auspices of the

AMERICAN SOCIETY OF AGRONOMY

VOLUME
Edited by A. G.
Camp

II

NORMAN

Detrick, Frederick,

Maryland

ADVISORY BOARD
R.

BRADFIELD


K.

S.

LAUDE
C. E. MARSHALL
N. P. NEAL
H. H.

QUISENBERRY
RICHARDS
V. G. SPRAGUE
E. WINTERS

L. A.

1950

ACADEMIC PRESS

INC.,

NEW YORK

PUBLISHERS


Copyright 1950, by

ACADEMIC PRESS

INC.

125 EAST 23RD STREET

NEW YORK

10,

N. Y.

All Rights Reserved

No part of this book may be reproduced in any
form, by photostat, microfilm, or any other means
without written permission from the publishers.
t

PRINTED IN THE UNITED STATES OP AMERICA


CONTRIBUTORS TO VOLUME
J.

II

Agronomy, Texas Agricultural and
Mechanical College System, College Station, Texas.

E. ADAMS, Head, Department of

GILBERT H. AHLGREN, Professor of Farm Crops, Rutgers University,
Brunswick, New Jersey.

W. H. ALLAWAY, Research

New

Professor of Soils, Iowa Agricultural Experi-

ment Station, Ames, Iowa.

HENRY D. BARKER,
ture, Beltsville,

Principal Pathologist, U. S. Department of Agricul-

Maryland.

CHARLES A. BENNETT, Principal Agricultural Engineer, U.

S.

Department

of Agriculture, Cotton Ginning Laboratory, Stoneville, Mississippi.

E. C. CHILDS, Assistant Director of Research in Soil Physics, School of
Agriculture, University of Cambridge, England.
F.

M. EATON,

Principal Physiologist, U. S. Department of Agriculture,
College Station, Texas.

ENSMINGER, Associate Soil Chemist, Alabama Agricultural Experiment Station, Auburn, Alabama.

L. E.

R. F. FUELLEMAN, Professor of Agronomy, University of

Illinois,

Urbana,

Illinois.
J.

C. GAINES, Professor of Entomology, Texas Agricultural and Mechanical College System, College Station, Texas.

N. COLLIS-GEORGE, Demonstrator, School of Agriculture, University of
Cambridge, England.

M. K. HORNE,

JR.,

Dean, School

of

Commerce and Business Administra-

tion, University of Mississippi, University, Mississippi.

WESLEY KELLER,

Geneticist, U. S.

Department

of Agriculture,

Logan,

Utah.

W. K. KENNEDY,

New
J.

Professor of Agronomy, Cornell University, Ithaca,

York.

E. KNOTT, Professor of Truck Crops, University of California, Davis,
California.

HELMUT KOHNKE,
versity

Department of Agronomy, Purdue UniAgricultural Experiment Station, Lafayette, Indiana.
Soil Scientist,


CONTRIBUTORS TO VOLUME

VI

II

0. A. LORENZ, Assistant Professor of Truck Crops, University of California, Davis, California.

WILLIAM E. MEEK, Senior Agricultural Engineer, U.

S.

Department

of

Agriculture, Stoneville, Mississippi.

R. B. MUSGRAVE, Associate Professor of Agronomy, Cornell University,
Ithaca, New York.
R.

W. PEARSON,

Senior Soil Scientist, U. S. Department of Agriculture,

Auburn, Alabama.

MAURICE

L. PETERSON, Assistant Agrononvist, California Agricultural

Ex-

periment Station, Davis, California.

JOHN

T. PRESLEY, Head, Department of Plant Pathology and
Physiology,
Mississippi Agricultural Experiment Station, State College, Mississippi.

T. R. RICHMOND, Professor of Agronomy, Texas Agricultural
Experiment
Station and Senior Agronomist, U. S. Department
of Agriculture,
College Station, Texas.
F. F. RIECKEN, Research Professor of
Soil*,
ment Station, Ames, Iowa.

GUY D.

SMITH, Senior
Ames, Iowa.

Soil Correlator, U. S.

Iowa Agricultural ExperiDepartment

of Agriculture,

HARRIS P. SMITH, Professor of Agricultural
Engineering, Texas Agricultural Experiment Station, College
Station, Texas.


Preface
In the preface to Volume I it was pointed out that the pressure of
progress in the many sub-fields that collectively constitute agronomy
tends to produce specialists who find it difficult to keep abreast of newer
developments somewhat removed from their immediate interests, yet of
professional importance to them. It was further explained that the editors were not inclined to quibble about the precise definition of the word
"agronomy." In selecting topics for treatment they would be guided
more by the consideration of what might be useful to agronomists than

what

The authors

arc urged to present, as far
as possible, unified, complete and authoritative accounts of the recent
constitutes agronomy.

developments in their particular
to time as

Topics will reappear from time

develop.
the mid-century year. It would be presumptious on the part of
publication so recently established as Advances in Agronomy to

This

a

fields.

new material and new viewpoints

is

prepare a mid-century number delineating and weighing the achieve-

ments and accomplishments of the first half of this century. The editor
had no difficulty in resisting the urge to follow the lead set in this matter
by long-established and more popular publications. However, this
thought did set in train some speculations as to what topics might have
been selected for a similar volume had one been prepared fifty years ago.
Largely, this amounted to a realization of the topics which would not
have been included because their development has taken place almost
entirely since 1900.
Crop improvement through genetics, soil physics,
and soil genesis are examples.
cursory glance at the contents of this
volume will showr that about half of them would not have appeared in

A

1900 edition. Thus fast has agronomy grown.
Speculation in another direction is possible. One might consider the
extent of the agronomic achievements of the past half century in terms
of the changes in U. S. agriculture and agricultural practice. These are
dramatic enough. Here is a nation which in fifty years has doubled in
population but has no more farms now than then. Twenty-five per cent

any form

in a

more acres are harvested, meat production has been doubled,

fertilizer

consumption has increased eight-fold, but there are fewer sheep, and
far fewer horses and men on farms now than at the turn of the century.
Perhaps in the last lies a clue to much that has been accomplished by the
mechanization of many operations through the availability of power
equipment.
What can be anticipated in the remainder of this troubled century?
vii


PREFACE

Vlii

Have the easy things been done? Will the tempo of progress be slowed?
Are the land use systems that have developed stable or exploitive? Will
the crop surpluses of domestic production be absorbed in meeting the
deficits elsewhere, or are

they merely a temporary feature soon to be

dissipated by population increase? Should production be curtailed in the
interests of conservation? Will there be changes in food habits on the

part of the consumer that will call for great shifts in types of farming?
Will the era of surpluses even give way to a period when the demands
for food will be such that exploitive land use

The

resolution of

many

is

forced upon us?

vital questions such as these will not pri-

the hands of those practicing the profession of agronomy,
yet they will be required to use all their skills and ingenuity and resourcefulness in providing the solution to the innumerable practical prob-

marily

lie in

lems that taken together will determine the answers to such major
questions. Subsequent volumes of the Advances will record and sum-

marize their methods, recount their achievements and measure their
accomplishments.
A. G.
Frederick, Md.

October, 1950.

NORMAN


CONTENTS
Contributors to

Volume

Page
v

II

Preface

vii

Cotton
COORDINATED BY J E. ADAMS, Texas Agricultural and Mechanical College System,
College Station, Texas
I.

Introduction,

BY

J.

E.

ADAMS

2

Competitive Position of Cotton Among Fibers, BY M. K. HORNE, JR.
III. Physiology of the Cotton Plant, BY F. M. EATON
IV. Diseases of Cotton, BY JOHN T. PRESLEY
V. Insect Pests, BY J. C. GAINES
VI. Improvements in Production Practices,
BY WILLIAM E. MEEK and HARRIS P. SMITH
II.

VII. Improvements in Ginning Practices, BY CHARLES A. BENNETT
VIII. Fiber Properties and Their Significance, BY HENRY D. BARKER

IX. Breeding and Improvement,
References

BY

T. R.

L. E.

I.

S.

26
32

40

...
...

RICHMOND

50
56
63

Nitrogen

ENSMINGER AND R. W. PEARSON, Alabama
and U.

5
11

74

Soil

BY

.

Department

Agricultural Experiment Station,

of Agriculture,

Auburn, Alabama

Introduction

81

Factors Affecting Nitrogen Content of Soils
III. Nature of Organic Nitrogen in the Soil

83

II.

87
89

IV. Nitrogen Transformations
V. Effect of Cropping Practices on Nitrogen Level
VI. Nitrogen Economy of Eroded Soils

VII. Commercial Nitrogen vs. Barnyard Manure and Green Manures
VIII. Nitrogen Trends in Various Parts of the U. S

94
98
.

.

.

100
104

109

References

Vegetable Production

BY

J.

E.

KNOTT AND

0. A. LORENZ, University of California, Davis, California

Introduction

114

II. Fertilization

116

I.

III.

Trace Elements

120

IV. Development of New Vegetable Varieties
V. Utilization of Heterosis

ix

121

128


CONTENTS

X

Page
VI. Growth Control Techniques
VII. Labor Saving Devices
VIII. Possible Future Developments
References

Prairie Soils of the

135
141

151

152

Upper Mississippi Valley

BY GUY D. SMITH, W. H. ALLAWAY AND
culture,

F. F. RIECKEN, U. S. Department of Agriand
the
Iowa
Ames, Iowa,
Agricultural Experiment Station, Ames, Iowa

Introduction

I.

157
of

II. Characteristics

Modal

a

Prairie

III. Variability of Prairie Soils as

Soil

159

Functions of Soil-Forming Factors

.

.

.

166

IV. Classification of Prairie Soils

192

V. Distribution of the Prairie Soils
VI. Crop Yields from Prairie Soils
References

197

196

203

Ladino Clover

BY

GILBERT H. AHLUREN AND R. F. FUELLEMAN, Rutgers University, New Brunswick,
New Jersey, and University of Illinois, Urbana, Illinois
I.

II.

III.

History and Distribution

208

and Adaptation
Establishment and Management

209

Characteristics

213

IV. Utilization

V.

226

Summary

230

References

230

The Control of

BY

I.

II.

III.

E. C. CHILDS

Water

AND N. COLLIS-GEORGE, School of Agriculture, University
Cambridge, England

The Scope of the Review
Research Methods

The

Soil

of

234

^

234

,

Basic Approach

235

IV. Drainage and Irrigation
References

258
269

Preservation and Storage of Forage Crops

BY

R. B. MUSGRAVE AND

W. K. KENNEDY, Department

University, Ithaca,
I.

II.

New

of

Agronomy, Cornell

York

Introduction

Measurements

III. Silage

274
of

Changes

in Quality

During Preservation and Storage

.

275
279


CONTENTS

XI

Page
IV. Field-Cured

2M

Hay

V. Barn Hay Drying
VI. Artificial Drying
VII. Experiments Comparing Silage, Barn-Cured and Field-Cured
VIII. Conclusions
References

299
304

Hay

.

.

306
309
311

The Reclamation of Coal Mine Spoils

BY HELMUT KOHNKE, Purdue

University Agricultural Experiment Station,
Lafayette, Indiana

I.

II.

III.

IV.

V.

Introduction

318

The Condition of Spoil Banks
Mrthods of Testing Spoil Bank Materials
Land Use Capabilities
Methods of Revegelation

319

Economic Aspects

341

VIII Legislation
IX. Discussion
X. Summary
XI. Acknowledgments

Reformers

332

335

338

VI. Grading
VII.

330

344

344

347
348

...

349

Irrigated Pastures

BY WESLEY KELLER AND MAURICE

L. PETERSON, U. ft. Department of Agriculture,
Logan, Utah, and California Agricultural Experiment Station, Davis, California
I

II.

III.

Introduction

351

Pasture Soils
Choosing Productive Mixtures

352

IV. Establishing Pastures
V. Management of Pastures

VI. Economy of Pastures
VII. Pastures in Relation to Other Sources of Feed

References

Author Index
Subject Index

356

360
365

375
380

382
385
402



Cotton
Coordinated by

J.

E.

ADAMS

Texas Agricultural and Mechanical College System, College Station, Texas

CONTENTS
Page
I.

II.

Introduction by

ADAMS

E.

2.
3.

4.

2

,

Among Fibers by M. K.
Cotton Loses Markets
End-Uses of Cotton and Other Fibers
A Static vs. a Dynamic Position for Cotton
Need for Expanded Research

Competitive Position of Cotton
1.

III.

J.

HORNE,

JR.

Physiology of the Cotton Plant by F. M. EATON
1. Floral Initiation and Plant Development
2. Mineral Nutrition
3.
4.
5.
6.

5

5
6
8
9
11

11

14

Nitrogen
Carbohydrates, Nitrogen and Fruitfulness
Effect of Drought on Plant Composition and Fruiting
Drought and Other Factors Affecting Boll Development and Lint

20
22
24

24

Properties
7.

.

Oxygen Requirements

for

Root Growth

25

PRESLEY

1.

Seed Treatment

2.
3.

Phymatotrichum Root Rot
Fusarium Wilt

4.

Verticillium Wilt

5.

Bacterial Blight

26
26
26
28
29
30

6.

Root-Knot

31

7.

Summary

32

IV. Diseases of Cotton by J. T.

V. Insect Pests by

J.

C.

GAINES

1.

Thrips

2.

Cotton Aphid
Cotton Fleahopper
Boll Weevil
Bollworm
Pink Bollworm

3.
4.

5.

6.
7.

8.

9.

10.

Hemipterous Insects
Cotton Leafworm
Spider Mites
General Recommendations for Chemical Control

VI. Improvements in Production Practices
1. In Humid Areas by W. E.
2. In Low-Rainfall and Subhumid Areas by H. P.

40
40

MEEK
i

32
32
33
33
34
36
37
38
38
39
40

SMITH

46


2

J. E.

ADAMS
Page

VII. Improvements in Ginning Practices by C. A.

3.

Regulation of Moisture
Cleaning
Extraction and Interrelated Processes

4.

Summary

1.

2.

BENNETT

VIII. Fiber Properties and Their Significance by H. D.
1. Fiber Structure and Development
2.
3.
4.

52
53
55

BARKER

56
56

58

Fiber Length
Fiber Strength
Fiber Fineness

5. Significance of

50

50

59
60

Fiber Properties

IX. Breeding and Improvement by T. R.
1. General

62

RICHMOND

63
63

2.

The Breeding Problem

64

3.

Breeding Systems
Hybrid Vigor in Fi and Advanced Generations

66

4.
5.

Special Phases

70
71

74

References

I.

INTRODUCTION
J.

E.

ADAMS

Texas Agricultural and Mechanical College System, College Station, Texas
is the most important cash crop grown in the United States,
the only major crop which produces the 3 products, fiber," food and
When all phases of the industry are considered, some 20 to 25

Cotton

and

is

feed.

million people are wholly or partially dependent on cotton as a source of
income. Of these, approximately 1,500,000 are engaged in production
in ginning, marketing and processing.
fact that the entire fruit of the cotton plant

and 3,000,000

The

is used makes it an
unusual crop. In addition^to lint, the embryos or "meats" of the seed
furnish both a protein concentrate and a high-grade oil.
The "hulls"
or seed coats are used as feed, as well as the concentrate. The fuzz left

on the seed
fibers

after

known

normal ginning

is

removed mechanically and these short

as "linters" are used in upholstering, low-grade mattresses,
of cellulose for synthetics.

and as a source

The

present status of cotton is both artificial and in a state of flux.
Although cotton lint is the most versatile fiber known when all end-uses
are considered, economic conditions since the early thirties, with intermittent acreage control and price subsidies, have resulted in increased
competition of old and new synthetic fibers. Unrestricted production

during and following the war, with impending acreage controls, is reTable I, released as of December 8, 1949, by the Bureau of

flected in


COTTON

3

Agricultural Economics, Austin, Texas.
Every cotton-producing state
shows an increase in acreage in 1949 over 1948. In spite of lower production per acre in some areas, there was a net increase of 1,157,000 500-lb.
gross-weight bales in 1949, as compared with 1948. More striking is
the increase of 4,728,000 bales in 1949 over the average of 11,306,000

bales in the 1938-1947 period. The increase in production in the irrigated areas, particularly California and also New Mexico and Arizona,
is

phenomenal.
Although the sections on production treat mechanization of the cotton
crop in many of its details, it is to be emphasized that mechanization
lor all areas really dates to the World War II period, during which there
was an intensification in research and more ready acceptance by the
farmer due to the dearth of labor. Development of flame cultivation,
rotary hoes, efficient fenders for cultivation equipment, along with the
culmination of years of research on harvesting machinery, resulting in
usable harvesters, has made full mechanization of the crop a reality in
some sections. Remaining difficulties for other areas and particular
seasons are yielding to intensified research.
Estimates furnished by the National Cotton Council indicate that

approximately 2900 spindle-type pickers were used in 1949. Mississippi
California used approximately 850, Arkansas, 350, and
led with 990.
Louisiana, 200. The acreage harvested would be difficult to estimate,
but probable harvest per machine varied from 100 to 250 acres.
of better than 7000 strippers were used, with the

accounting for at least 6000.
the estimated

number being

A

total

Texas High-Plains area

Oklahoma was the only other large user,
The capacity per machine ranges from

950.

125 to 400 acres, depending on local conditions.
Considering that practically all of the cotton harvesters have become
available since the war, the increase in use of machinery is outstanding.
feeling that costs of production for cotton must eventually

The general

be radically lowered, leads to the conclusion that production per acre
Better fertility practices, control of insects and dis-

must be increased.

eases, better varieties of cotton for mechanical harvesting, along with
more compl^e^and assured defoliation are of prime importance.

All of the cottons of the world, whether cultivated or wild, belong
to the genus, Gossypium. They may be divided into 3 main groups: (1)
Old World or Asiatic cultivated (n = 13), (2) New World or American
26), and (3) wild, (n = 13, with one anomalous exception).
Though the reported number of species of Gossypium varies
widely, depending on the classification system employed and the inclination of the taxonomist, a recent work by Hutchinson et al. (1947) (see

cultivated (n

=

References in IX) recognizes twenty.

These writers place the cultivated


J. E.

ADAMS

cottons under four species: G. arboreum L., G. hirsutum L., and G. barbadense L. The first two are designated as Asiatic and the last two as
American cottons, and all bear spinnable seed hairs, called lint, which

them from the wild cottons which do not have spinnable
American cultivated cottons (n = 26), according to the theory
advanced by Skovsted (1937) (see References in IX) and confirmed
independently by Beasley (1940) and Harland (1940) (see References
distinguishes

lint.

TABLE

I

Cotton Production in United States

*

Allowances made for interstate movement of seed cotton for ginning.
Kansas, and Kentucky for all years and Nevada for 1948 and 1949.
c
Included in State and United States totals. Grown principally in Arizona,
Mexico, and Texas.
b

Illinois,

New


COTTON

5

in IX) , are tetraploids which have arisen by amphidiploidy from hybrids
of Asiatic (n = 13) and American Wild (n = 13) parentage.
This paper will present important aspects of the production of cotton

each of which, because of space limitations, can be treated only

II.

COMPETITIVE POSITION OF COTTON

AMONG

briefly.

FIBERS

M. K. HORNE, JR.
University of Mississippi, University, Mississippi

1.

Cotton Loses Markets

Except for the abnormal experience of the war and early postwar
years, it can be said that over the past 4 decades the per capita consumption of cotton in this country has shown no tendency to rise. Over
this long period, it has gravitated around a central figure of 25 or 26
Ibs. a year, displaying no trend either up or down.
In net effect, the
entire new market created by rising standards of living has been captured by rayon, paper, and to a smaller extent, other materials. In this
fact we have an indication of what competition has done to the cotton
market down to the present time, and why the students of the demand
for cotton are engrossed in its competitive position.
There are at least 35 materials which give cotton substantial
tition.

The more

interesting ones include

rayon in

its

compe-

various forms,

paper, glass fiber, nylon and the other fibers of synthesized polymers,
the synthetic protein fibers, plastic film, and jute, ramie and the other
bast fibers.

In seeking the competitive meaning of these numerous materials, it
seems helpful, and in some degree defensible, to think primarily in terms
of rayon. This fiber is not only cotton's biggest, but by a wide margin
its most serious, most threatening competitor.
In Project IV of the
cotton fact-finding program, "A study of the agricultural and economic
problems of the Cotton Belt," presented in 1947 before the Cotton Sub-

committee of the Committee on Agriculture, U. S. House of Representatives, it was found that some form of rayon was cotton's closest
competitor in 65 out of a group of 106 end-uses analyzed. In 25 years,
rayon has advanced from a trivial position among all fibers to second
place in the volume consumed in the United States. In 1948, 1,124,000,000 Ibs. of rayon were produced in this country. Factory capacity has
now reached an estimated 1,235,000,000 Ibs., or the equivalent in usable
fiber of about 2,900,000 bales of cotton.
This amounts to 48 per cent
annual
the
of
of
cotton in this country during the
average
consumption


M. K. HORNE, JR.

6

decade of the 1930's, and to 35 per cent of the cotton consumption in the
Two-thirds of this rayon
best year of that decade, which was 1937.
that
of
built
end
decade. With the return
since
the
been
has
capacity
to a buyer's market for textiles in the United States, cotton is inevitably
feeling a terrific impact from a competitor which has grown so rapidly

become so large. In foreign lands, the tendency is for rayon to
assume an even stronger competitive position than in the United States.
ajid

2.

End-Uses

Every end-use market
ments in price and in the
a fiber product.

of Cotton

and Other Fibers

for cotton has a separate pattern of require-

scores of distinct qualities which characterize
Likewise, there is a separate price and quality pattern

for every competing material. Most materials are quite different from
cotton in price and quality, and they must compete in a more limited
number of end-uses where their special characteristics give them an ad-

vantage.

As competitors

centrating upon and

of cotton they are specialty materials, conlimited to some segment of cotton's end-use markets.

Paper, for example, is cotton's second most aggressive competitor
today. It has a big advantage in price and a few small advantages in

Within a limited range of uses, these factors can sometimes
overcome the important advantages of cotton in other properties. Paper
is a formidable competitor in the great bag market, and in large sectors
of the towel, cordage, napkin, and handkerchief markets.
Its quality
quality.

is

being steadily improved through research.

But paper's

texture, strength, and absorbency quite obviously restrict
of the cotton market.

it

differences in

to a fraction

For a second example, the leading synthetics other than rayon are
considered. They are all far above the price range of cotton. One may
be tempted to reason that since rayon came down to the price of cotton,
these other materials can eventually do likewise. Any such reasoning
would seem to be premature, ai least for the better fibers. In the strong,
resilient synthesized polymers, including nylon, the textile scientists point
out that basic differences in the chemical approach seem to invalidate

the idea of ever bringing costs down to the level of rayon. At the same
time, these various synthetics are quite superior to cotton in some qualiThere are certain uses for cotton
ties, and quite inferior to it in others.
in

which their patterns of quality can overcome the price handicap, but

again these uses are limited.

an ever-increasing degree
it competes for markets, not because of its differences from
cotton, but
because of its similarities to cotton. Its price and quality pattern has
relentlessly shaped itself toward the price and quality pattern of cotton.

Rayon ,is

distinguished

by the

fact that to


COTTON

7

generally, it can be said that today rayon is in the same price
with
cotton. In reference to quality, there still are sharp differences
range
between the two fibers, but rayon has made marvelous progress in over-

Very

coming its quality handicaps through research. That progress can be
seen in the development of staple fiber, in delustering, in crimping, in
higher wet and dry strength, in softer yarns, and in better finishes for dimensional stability. Several of rayon's biggest quality handicaps remain,
but we cannot overlook the fact that the extensive research program
of the rayon industry is going vigorously forward.
cotton, rayon looks less and less like a specialty fiber
like a fiber

whksh eventually

may

As a competitor of
and more and more

contend for virtually

all of cotton's

markets.

The two

chief weapons with which rayon might be expected to impresent
competitive position are: (1) the lowering of price;
prove
and (2) the improvement of quality. Which of these two possibilities
is the more threatening to cotton?
From the excellent research in recent
its

now seems

fairly clear that the rayon industry is likely to rely
on
improved quality to buttress its competitive position. The
primarily
era of continual price reductions in rayon, year by year, seems to have
ended in 1938. The average production cost of viscose staple at a recent
time was 29 cents a pound. This of course was before any allowance
The selling price of viscose staple was 35 cents in
for income tax.

years,

it

March, 1950.

Obviously

tion will be achieved

by

unlikely that any drastic price reducreducing profits unless market conditions take
it

is

On the side of cost reductions, it must be
that
real
technical
is still being made, but the nature
progress
recognized
of the cost is such that the further reductions are likely to be much more
a serious turn for the worse.

gradual than in the past.

Therefore,

seems that any declines in the
be modest in amount unless
For types of rayon other than

it

selling price of viscose staple are likely to

a serious business recession occurs.

viscose staple, the possibilities of cost reductions, through technical advances, may be somewhat greater, but nowhere can any reductions of

major proportions be foreseen.
On the other hand, the rayon industry is spending large sums of money
on research, a major part of it apparently aimed at the improvement of
quality. It is perhaps a reasonable guess that the present rayon research
and technical-service programs of the 5 leading companies are costing
ten million dollars a year. We can never predict what research laboratories may bring forth, but we must be impressed with the success of the
rayon research program down to the present time. A continued, and
perhaps an accelerated, improvement in the quality of the various rayons
appears to be the greatest threat to the market for cotton. A continuing


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