さつまいも英語版8/16 06.3.23 4:28 PM ページ 3

Sweetpotato Packing-Box Art (side panels)

The Other Potato

Sweetpotatoes in the USA

The PlayBoy brand used for North Carolina sweetpotatoes has been used since 1942 (no connection to
the later established, similarly named magazine).
The brand derives from the “classy kind of guy” imageof the Wayne E. Bailey Produce Co.’s two founders.

by Barry Duell
Tokyo International University, Professor
Kawagoe Friends of Sweetpotatoes, Chair
Chef’s Pride brand of Harold Quebedeaux Produce, Inc.
Louisiana-produced jumbo sweetpotatoes.

This design recalls a traditional image of theSouth as popularized in Gone with the Wind.
Harold Quebedeaux Produce, Inc. brand,
Louisiana.

Vardaman, Mississippi, produced sweetpotatoes.
This town’s sweetpotato festival is introduced in
the article, “Sweetpotato Festivals” (p. 40).

“Sweet Carolina” is a sweetpotato brand from the top
producing state, North Carolina.

This limited edition funded by

The Foundation for Development of Root and Tuber Crops (Japan)“Southern Belle” evo
beautykes ananideal osweetp d grace (achf feminie
otatoesine?). Bra ved through eQuebe
nd namadeaux
Produce of Ha tinge, Inc.,roldLouisiana.

さつまいも英語版8/16 06.3.23 4:28 PM ページ 5

The Other Potato

Sweetpotatoes in the USA
by Barry Duell

Kawagoe, Saitama, Japanさつまいも英語版8/16 06.3.23 4:28 PM ページ 7

Barry Duell

Table of Contents

The Other Potato: Sweetpotatoes in the USA

Foreword: Little Known Aspects of Sweetpotato in the USA ───────── 2First edition
Published September 2000 by Barry Duell
Written and edited by Barry Duell
Printing and design by Spoon, Inc., Tokyo, Japan

Acknowledgements ──────────────────────────── 3Translated and revised from the Japanese by Barry Duell
Originally published as Amerika satsumaimo jijou
Written by Barry Duell
Published March 1999 by Kawagoe Friends of Sweetpotatoes
Kawagoe, Saitama, JapanFor corrections and additions,visit the Web site:www. tiu. ac. jp/~bduell/sp/usasp/

Sweetpotato Production and Consumption ───────────────── 8

The author welcomes comments at:
Barry Duell
Kawagoe Friends of Sweetpotatoes, Chair
Tokyo International University
School of Business and Commerce, Professor
1-13-1 Matoba-kita
Kawagoe, Saitama 350-1197
JAPAN

Sweetpotato Packing-Box Art──────────────────────── 5
Map and Statistics: Sweetpotato and Potato at a Glance ─────────── 6

Sweetpotato Farming──────────────────────────── 16
Research: National Sweetpotato Collaborators Group ──────────── 22
Organic Farming of Sweetpotatoes ───────────────────── 26
Sweetpotatoes: What’s in a Name? ───────────────────── 28
Most Common Ways of Eating Sweetpotato ──────────────── 30
Sweetpotato in Literature: The Yearling and Sweetpotato Pone ────── 34
Eating Out: Sweetpotato at the Restaurant ───────────────── 36
Sweetpotato Festivals ─────────────────────────── 40
President George Washington and Sweetpotatoes ───────────── 42
George Washington Carver and Tuskegee University──────────── 43

E-mail: bduell@tiu.ac.jp
Cover:
Map- USA primary sweetpotato-growing states are colored dark orange. Refer to“Map and Statistics: Sweetpotato and Potato at a Glance” (p. 6).

c 2000 by Barry Duell; all rights reserved.
Copyright ○Printed in Japan.

Photos- Side panels from sweetpotato packing-boxes (18 kg/40 lb). Refer to“Sweetpotato Packing-Box Art” (p. 5).

1

さつまいも英語版8/16 06.3.23 4:28 PM ページ 2

Acknowledgements

Foreword

Little-Known Aspects of
Sweetpotato in the USA
Hiroshi Inoue
Curator, Sweetpotato Museum
Kawagoe City, Saitama Prefecture, Japan

Barry Duell (USA) has lived in Kawagoe City, Japan, for more than 20
years, and teaches English and Cultural Anthropology at Tokyo International University.
Duell chose the study of sweetpotato as a way to better understand his
adopted town, Kawagoe, due to that crop’s association with this town fromtimes past.
Sweetpotato has many interesting aspects. Studying it in relation to
Kawagoe led Duell to learn about sweetpotato’s role in Japanese and othercountries’ cultures.
The International Society for Tropical Root Crops is an important academic society associated with sweetpotato, a plant of tropical origin. Duellhas been attending this society’s symposium that meets triennially in different countries, joining with other experts to promote understanding of tropical root crops. A person such as this is eagerly welcomed as someone who
could write an easy to understand book about sweetpotato in the USA.
Two sweetpotato organizations in Kawagoe are the grassroots “Kawagoe
Friends of Sweetpotatoes” and the “Kawagoe Sweetpotato Products Promotion Board.” Eiji Yamada, manager of both groups, planned the productionof the Japanese edition of this book. Kawagoe’s sweetpotato groups havetaken the lead in promoting understanding of sweetpotato’s role in Japan’sculture, so it is with pride that we welcome the Japanese edition of this bookabout sweetpotato in the USA.
May this book prove useful to its many readers.
translation of the Foreword from the 1999 Japanese edition of thisbook, Amerika Satsumaimo Jijou

2

This little book introduces various aspects of sweetpotatoes in the USA.
Though a very minor crop that plays only a small role in the diet of mostAmericans, there are, nonetheless, aspects of US sweetpotatoes introduced
here that will hopefully be of interest to the reader. This book is a revisionand translation of Amerika satsumaimo jijou which was published inJapanese in March 1999.
The author wishes to thank the many people and organizations whichhave contributed to the making of this book. For valuable information andphotos, thanks go to Mike Cannon (Louisiana State University), Christopher
Clark (Louisiana State University), L.J. Duplechain (Louisiana Sweetpotato
Commission), Gilmer Chamber of Commerce (Texas), Velera Jones, Don
LaBonte (Louisiana State University), Livingston Chamber of Commerce(California), Velma Duell McConnell, and Ocilla Chamber of Commerce(Georgia).
For much constructive information, thanks also go to Sheryl Badeaux(Louisiana Yambilee Organization), George Wooten (Wayne E. Bailey
Produce, Inc., North Carolina), Scott Bissette (North Carolina Departmentof Agriculture and Consumer Services), Pat Daugereaux (Church Point,
Louisiana, Rod’s Supermarket owner), Gary Hamaguchi (Livingston,
California, sweetpotato farmer), Deborah Hathaway (North Carolina Yam
Festival organizing committee), Sue Johnson-Langdon (NC Sweetpotato
Commission, Inc.), Blaine Joubert (Church Point, Louisiana, sweetpotato
farmer), Stanley J. Kays (University of Georgia), Wayne McLaurin(University of Georgia, and National Sweetpotato Collaborators Group),
Tom Nakashima (Livingston, California, sweetpotato farmer), Harold
Quebedeaux (Harold Quebedeaux Produce, Inc., Louisiana), Jonathan
Schultheis (North Carolina State University), Bill Weir (University ofCalifornia), and Karen Wright (Vardaman Sweetpotato Festival Committee,
Mississippi).
Thanks go to my parents, Cal and Velma McConnell, and my brothers,
Gary, Bart and, Kevin, for advice in naming this book.
The above people and organizations have put up with answering my end-3

さつまいも英語版8/16 06.3.23 4:28 PM ページ 4less questions, helping this book more accurately portray the situation ofsweetpotato in the USA. The author apologizes for inadvertently leaving out
the names of any parties to whom due credit should be given.
The concept for this book grew out of my having grown up in the USA,but having lived many years in Kawagoe City (in Saitama Prefecture, Japan)
which has a strong sweetpotato image. Eiji Yamada, Business Manager ofthe Kawagoe Friends of Sweetpotatoes, suggested and encouraged the writing of the Japanese edition of this book, and was heavily involved in its
design. Hiroshi Inoue, Kawagoe Sweetpotato Museum Curator, wasinvolved in editing the contents of the Japanese edition to ensure the bookwould be of interest to the lay reader. Thanks go to these two for their help
in creating the original Japanese edition of this book, upon which thisEnglish edition is based. Thanks go, too, to the staff at Spoon for theirdesigning and printing this book.
The author takes responsibility for the entire contents of this book. Care
has been taken to accurately portray the situation of sweetpotato in the US,
but should the reader find errors, please kindly inform this author.
All photos are by the author unless otherwise noted.
The author welcomes comments.

Barry Duell

July 2000

by Eiji Yamada(Imo in Japanese refers to sweetpotato,
as well as other tubers)

4

Sweetpotato Packing-Box Art
Sweetpotato box art began in the late 19th century. To
safely ship produce to the Eastern Seaboard, California shippers started putting produce in wooden boxes. To appeal tothe buyers, California and other shippers began putting colorful lithographed labels on their boxes. In the case of sweetpotatoes, a box contained 50 lb (about 23 kg) and had a 23 cm
x 23 cm (9 in x 9 in) paper label. (See <p. 23>)
The main label printing firms were in San Francisco,California, with some others in the Southeast. A label’s complexity varied according to the budget of the farmer and shipper. The simplest sweetpotato label might only contain the
text “sweetpotato” along with the brand name, farmer or shipper’s contact information, box weight, grade, and so on. A
costlier label might have several colors with an appealing
design. These labels hint at the trends of the time.
From the 1950s, cardboard boxes gradually replaced woodones which finally disappeared in the early 1970s. Instead of a
special label that was printed for pasting on a wood box, labeling was printed directly on all sides of cardboard boxes. For
sweetpotatoes, these new boxes hold 18 kg (40 lb) withdimensions 25 cm (H) x 43 cm (W) x 32 cm (D) (10 in x 17 in x
13 in). (See Cover and <p. 11>)
Unfortunately, sweetpotato box art can usually only beappreciated by wholesale buyers. Retail merchants prefer tounpack sweetpotatoes for displaying to customers, discarding
the artistic boxes.

Reference:
Medley, R. John, Jr., Images of the Sweetpotato, An
American Art Form, Oracle, Arizona, USA, 1994.

5

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Map and Statistics

Sweetpotato and Potato at a Glance
Sweetpotato

PotatoAcreage (1997)¡31,310 ha (77, 380 ac)¡grown mostly in the SouthAcreage (1997)¡548,430 ha (1,355,200 ac)¡grown mostly in the North

Main growing state¡North Carolina

Main growing state¡IdahoAnnual per capita supply¡1.9 kg (4.2 lb)(FAO 1994-98 average)

Annual per capita supply¡62.3 kg (137 lb)(FAO 1994-98 average)

Popular ways of eating¡baked, candied, pie(See “Most Common Ways of
Eating Sweetpotato” <p. 30>)

Popular ways of eating¡fried, baked, mashed

Other¡No roasted sweetpotato vendors
like in Japan¡Thanksgiving (4th Thursday,
November) is consumption peak¡“Sweetpotato” also means ocarina,
a musical wind instrument¡Most US varieties have orange
flesh¡Most varieties soft and sweetwhen baked
Sweetpotato acreage in the USA is about 1/15 thatof potatoes. Sweetpotato acreage in Japan is less thanhalf that of potatoes, 46,500 ha (115,000 ac) versus
103,000 ha (255,000 ac) (all figures 1997).
Annual per capita sweetpotato supply in Japan is
7.1 kg (16 lb), almost 4 times that of the USA (FAO
1994-98 average).
Annual per capita potato supply in Japan is 24.7 kg(54.5 lb), about 40% that of the USA (FAO 1994-98
average).

6

Other¡Baked potato vendors at fairs¡Popular year round¡“Meat and potatoes” means“basic”¡Many varieties, mostly withbrown, red, or white peel, andwhite or yellow flesh¡Most varieties fluffy and dry when
baked, though some are moistfleshed

A 23 kg (50 lb) potato box. This brand is a pun on
Dublin, Ireland’s capital (“Irish potato” is an alternative
name for “potato.”) Norm Nelson, Inc., Washington
State.

otato
SweetpPotato1997 Harvested Acreage (USDA Agricultural Census)
Sweetpotato

Potato

Rank

State

Acreageq

USA
North Carolina

31,310 ha (77,380 ac)
11,760 ha (29,060 ac)

w

Louisiana

7,480 ha (18,480 ac)e

Mississippi

3,580 ha (8,840 ac)r

California
t
y

Rank

State

Acreage

q

USA
Idaho

548,430 ha (1,355,200 ac)
159,850 ha (395,000 ac)w

Washington

62,770 ha (155,100 ac)e

North Dakota

44,430 ha (109,800 ac)

2,840 ha (7,010 ac)r

Colorado

34,580 ha (85,450 ac)

Texas
Alabama

1,990 ha (4,910 ac)
1,410 ha (3,490 ac)ty

Wisconsin
Maine

34,520 ha (85,300 ac)
29,580 ha (73,090 ac)u

Florida,640 ha (1,580 ac)u

Minnesota

29,310 ha (72,430 ac)i,360 ha (880 ac),300 ha (750 ac)io

New Jersey
South Carolina

oOregonMichigan

23,330 ha (57,650 ac)
18,180 ha (44,930 ac)!0!1

Georgia
Virginia,270 ha (670 ac)!0!1

California
Florida17,600 ha (43,500 ac),250 ha (610 ac)

16,700 ha (41,260 ac)

7

さつまいも英語版8/16 06.3.23 4:28 PM ページ 8commercial vegetable production in the state. Top earners of 1998 agricultural
income, which in Louisiana include forestry, fisheries, wildlife, home gardens,

Sweetpotato Production andConsumption

and so on, were forestry ($1.3 billion), poultry ($390 million), and marine fisheries ($280 million), which together accounted for 49% of the state’s total.
Sweetpotato income ($35.045 million) accounted for 0.9%.
USA sweetpotato acreage pales before that of potatoes, the USA’s favorite

Acreage
In 1997, 31,310 ha (77,380 ac) of sweetpotato were cultivated in the USA.

tuber rated at 548,430 ha (1,355,200 ac). My native state of Oregon has only 4%of the potato acreage, but its 23,330 ha (57,650 ac) are more than the top three

USA Primary Sweetpotato Growing States (1997) 1)

sweetpotato states’ acreages combined.

Acreage

Share of
total

Value ofproduction ($1,000)

Share oftotal

USA total

31,310 ha (77,380 ac)

100％

211,180

100%

North Carolina

11,760 ha (29,060 ac)

38％

53,57025%

Louisiana

7,480 ha (18,480 ac)

24％

48,96023%

Mississippi

3,580 ha (8,840 ac)

11％

20,20010%

California

2,840 ha (7,010 ac)

9％55,69026%

USA total

208.665

100

Texas

1,990 ha (4,910 ac)

6％

14,5607%

Livestock and products

96.56846.3

Cattle and calves

36.094

17.3

Dairy products

20.98910.1

Chicken

14.152

6.8(Turkey

2.880

1.4)

112.09753.7

Corn, feed

20.456

9.8

Soybeans

18.321

8.8

Wheat

8.926

4.3

Vegetables

15.086

7.2

State

These five states account for about 90% of both total USA sweetpotato
acreage, and crop value.
California, the state with the largest agricultural economy, had less than 10%
of USA sweetpotato acreage in 1997. Even so, its 1997 sweetpotato income washigher than for any other state, and in 1998, at $55.057 million, it accounted for
0.2% of California’s agricultural income. Milk and cream were the largest
income producers at $4.3 billion, followed by grapes at $2.4 billion, together
accounting for 27% of the state’s agricultural income in 1998.

Crop Value
Comparison of sweetpotato crop value to that of major USA farm products.
USA Agricultural Farm Income (1997)
Commodity
Value (billions of dollars)

Crops

Percent

North Carolina’s 1998 sweetpotato income, $57.713 million, was higher than

Potatoes

2.622

1.3

for any of the state’s other vegetable or tuber crops. However, commodities

Tomatoes

1.645

0.8

such as chicken ($1.4 billion), hogs ($1.3 billion), and tobacco ($1.0 billion)

Lettuce, head

1.324

0.6

together accounted for 52% of the state’s agricultural income. Sweetpotato con-

(Sweetpotatoes

0.211

0.1)

12.790

6.1

stituted 0.8%.

Fruits/nuts

Sweetpotato in Louisiana generates more income than the total for other89

さつまいも英語版8/16 06.3.23 4:28 PM ページ 10

Grapes3.122

1.5

with 45% being primarily canned, but with some mashed sweetpotato flakes orOranges and tangerines

1.953

0.9

frozen croquettes being produced. The fresh market share increased to 60 ~70%

Apples1.575

0.8

by 1997. This trend is to the benefit of farmers since fresh market bound(Cranberries

0.350

0.2)

sweetpotatoes merit the highest market prices.

(Selected minor commodities in parentheses.)from Statistical Abstract of the United States 1999, U.S. Census Bureau,
December 1999

As the figures show, sweetpotato has a minor status in USA agriculture.

Varieties
Main USA Sweetpotato Varieties (1998 estimate)
Variety

Share oftotal acreage

Beauregard

75%

light roseorangeHernandez

10％

red

deep orange

ply of sweetpotato in the USA was as much as 13 kg (29 lb) during the 1920s.

Jewel, Cordner

5％

light copper/bronzeorange/orange

The Food and Agriculture Organization estimates this figure subsequently

Garnet2%

dark purple

deep orange

declined to 2 to 3 kg (4.5 to 6.5 lb) from the 1960s onward.

Kotobuki1%

reddish purple

light yellow

Other, light fleshed

4%

――

――

Others3%――――

Consumption
The US Department of Agriculture estimates that the annual per capita sup-The USA annual per capita supply of potatoes is about 30 times that of sweetpotatoes.

From the 1960s onward, potato consumption has gradually

increased, largely accounted for by increased consumption of French fries andpotato chips.
In 1982, an estimated 55% of the sweetpotato crop went to the fresh market,

Skin color

Flesh color

As the table shows, about 95% of the USA sweetpotato crop consists of highcarotene varieties reflecting consumer preferences. Two varieties account formost of the crop.
Variety preference changes with time as shown by Jewel accounting forabout 80% of the 1989 sweetpotato crop, but preference remains steady forhigh carotene, sweet varieties.
Varietal preference varies by region. For example, in 1998 almost 100% of

The late Shinji Matsuzaki of Japan and Tommy Lee exchange sweetpotato
farming experiences in Lee’s Alabama sweetpotato field (June 1991).

10

Beauregard, currently the most popular
USA sweetpotato variety, is named after
a Civil War era Confederate general.
Pictured is a General Beauregard brandsweetpotato box (see also “Sweetpotato
Packing-Box Art,” (p. 5))

11

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the Louisiana sweetpotato crop consisted of Beauregard, with that variety commanding about 90% of the crop in the surrounding states of Mississippi, Texas,
and Alabama.
In North Carolina, which has the highest sweetpotato acreage, 85% of the

Descriptions of Main USA Sweetpotato Varieties
Beauregard
Released in 1987 by Louisiana. Very high yielding. Light rose skin with orange
flesh.

crop in 2000 is Beauregard, with Jewel and Hernandez each having a 5% share.
This compares with 1979 when Jewel accounted for more than 90% of sweetpotato acreage.
Many Asian ethnic groups prefer a yellow, drier-fleshed alternative to theorange, moist-fleshed varieties most popular in the USA. Such a variety,Kotobuki is grown in California and marketed on the USA West Coast primari-

A hill of Beauregard also showing across-sectional view. (Photo courtesy of
Dr. Christopher Clark, Louisiana State
University)

ly to the many Asian ethnic groups living there.
The average USA consumer is only aware of two broad categories of sweetpotatoes, referred to as “yams” for orange, moist-fleshed ones, and “sweetpotatoes” for yellow, drier-fleshed ones. Supermarkets encourage this trend intheir marketing by generally not selling specific sweetpotato varieties, butinstead marketing these two broad categories.
Only some of the popular sweetpotato varieties predating the 1939 start of
the USA breeding program seem to be preserved in the USDA sweetpotato

Beauregard vines showing leaf shape,and upper and lower leaf views. (Photo
courtesy of Dr. Christopher Clark,
Louisiana State University)

Hernandez
Released in 1982 by Louisiana. High yielding. Red skin with deep-orange
flesh.

Jewel
Released in 1969 by North Carolina. High yielding. Light copper skin withorange flesh.

Cordner
Released in 1983 by Texas. High yielding. Bronze skin with orange flesh.

GarnetInformally released in California in the 1960s, and grown primarily there. Darkpurple skin with deep-orange flesh that is very sweet when baked.

Kotobuki
Introduced to the USA from Japan in 1986. Subtype of Kokei No. 14 (released1945). Reddish-purple skin with light-yellow flesh that is very dry when baked.

Other light-fleshed varieties

Enlarged view of second row from bottom. These 450 g (1 lb)
cans of sweetened sweetpotatoes are selling for $0.99(January 1999).
Store Owner Pat Daugereaux at the canned sweetpotato
section of Rod’s Supermarket (lower two shelves). Church
Point, Louisiana (January 1999).

Besides Kotobuki, there are a number of other light-fleshed varieties. One
example, Jersey type varieties, which predate sweetpotato breeding whichbegan in the USA in 1939, have brown skin with yellow flesh which bakes up
drier than the moist, orange-fleshed varieties most popular today. Jersey-typesweetpotatoes can still be found in some USA West Coast, North, andNortheast Coast markets.

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germplasm collection. For example, a source from the 1910s introduces four

Sweetpotato Puree Industry

low-carotene, drier fleshed varieties, none of which are listed in the USDA col-Research is being done to create sweetpotato varieties tailored to the spe-

lection. Likewise, the 1910s source and another from the 1930s introduce nine

cial processing needs of two types of puree makers. The babyfood industry

primarily high-carotene, moist-fleshed varieties of which only three are listed

depends on natural sweetness for its sweetpotato product. It also prefers a low-in the USDA collection. 2)

starch sweetpotato to be able to create a soft pureed product containing no

However, there are a number of seed exchange organizations which main-

additives. A well-cured sweetpotato is ideal for this purpose.

tain old varieties of crops, and exchange planting material among their mem-

The pie filling industry prefers a high-starch sweetpotato so as to have abers. Some heritage varieties of sweetpotatoes have been thus preserved.

firm product. The sweetness of the sweetpotato is immaterial as it can be

There are also commercial seed companies which maintain a stock of such tra-adjusted with added sugar. Ideal for this industry is a just-harvested, uncured

ditional sweetpotato varieties.

sweetpotato.

A Japanese sweetpotato breeder offers this opinion concerning the sparsity

Due to the specific requirements of these two puree industries, they areof sweetpotato varieties in the Japanese market, and the decline in heritage var-currently only able to obtain suitable processing sweetpotatoes during a limit-

ieties:ed time each year, thus keeping their processing plants idle most of the year.
The babyfood industry’s dream sweetpotato to allow year-round processing is“A blandness has come to the Japanese vegetable market due to there being

one high in alpha- and beta-amylase so that regardless of the time of year it isfew varieties of any particular vegetable available. When Japan’s economy wasprocessed, these enzymes can be harnessed to convert the starch to sugar.

rapidly expanding, there was pressure for overall standardization to make eco-

The pie filling industry’s ideal is to have a sweetpotato that will remain high innomic growth more efficient. Now, with the marketplace flush with products,

starch whether freshly harvested or cured due to a low amylase content.

and with a slow economy, we invite stagnation by ignoring customers’ wishes

Sweetpotato varieties for both industries are under development. 4)

for variety. We need to stimulate economic demand by increasing customer
choice. This can involve bringing back old varieties of familiar vegetables, but
as a researcher, I hope to bring many new varieties to market.” 3)
The USA sweetpotato market also offers few varieties to customers, butwork seems to be underway creating new unique sweetpotato varieties. Suchvarieties are unlikely to reach the general market, but to be tailored to theneeds of specific ethnic groups.

1) The figures vary annually due to vagaries of weather, prices, pests, and so on.
Though these USDA figures are the latest available, they are not necessarily representative of any state’s normal production.
(1997 Census Of Agriculture, Vol. 1, USDA, April 1999; Crop Values 1999
Summary, USDA, February 2000.)
2) Conolly, H.M., Illustrated Lecture on Sweetpotatoes: Culture and Storage,
USDA, Syllabus 26, Washington, D.C., April 21, 1917, p. 16.
Carver, George W., How the Farmer Can Save His Sweetpotatoes, and Waysof Preparing Them for the Table, Bulletin No. 38, November 1936, Tuskegee
Institute, Tuskegee, Alabama, USA, 4th edition, 1937, p. 3.
3) Opinion posted to the Japan Society for Root and Tuber Crops’ e-mail mailing list,
June 12, 1998, by Dr. Satoru Yamakawa, then Chief, Sweetpotato Breeding
Laboratory, Kyushu National Agricultural Experiment Station, Japan.
4) Wilson, Paul W., Don R. LaBonte, Durel J. Romaine, and Nolan P. Farace,“Selection of Sweetpotato Cultivars for Processing Characteristics,” Louisiana
Agriculture, Vol. 4, No. 4, Fall 1997, p.14.

14

15

さつまいも英語版8/16 06.3.23 4:28 PM ページ 16

A typical USA sweetpotato farm averages about 140 ha (60 ac). Growing
less than 120-140 ha (50-60 ac) of sweetpotato cannot bring a return on the nec-

Sweetpotato Farming

essary investment in machinery, storage and shipping facilities, and so on,amounting to $100 to $200 million for an average farm.
Almost all USA sweetpotato varieties grown are orange fleshed, high in

Most sweetpotato farms in the USA range fromcarotene. However, according to the region or ethnic group, tastes vary.

100 to 800 ha (250-2000 ac) in size. Of the roughly

Consumers in New York, New Jersey, or the West Coast tend to also prefer$3,000 per ha ($1,200 per ac) cost of sweetpotato

drier varieties with a yellow flesh. Southern Florida, with a high proportion of

production, about one-third goes for labor costs.

Cuban and other Hispanic population tends to grow more white-fleshed sweet-

Farmers largely depend upon migrant labor sincepotatoes high in starch. This dry type introduced from the Caribbean area isintensive labor is needed twice a year: May and Juneavailable fresh year-round in Miami markets. The Food and Agricultural

slip planting time, and August to November harvest time.

Organization (FAO) estimates that Cuba had a per capita supply of 10.6 kg

Though labor costs account for about one-third of sweetpotato production,(23.3 lb) of sweetpotato per year (1994-98 average). The 1990 US Census

migrant laborers are primarily paid the federal minimum wage, $5.15 per hour.

showed that 30% of the Dade County, Florida population is of Cuban origin. So

Migrant laborers from Mexico are on the increase, but the low wages make itsweetpotato consumption in southern Florida tends to be high. The area isdifficult to attract dependable workers. Additional labor costs include insur-

warm enough to grow two sweetpotato crops per year.

ance for laborers, work safety training, and filing of relevant paperwork for

The West Coast has higher populations of Asian ethnic groups. Meeting thetaxes and other purposes. Between 1991 and 1997, the minimum wage gradu-

needs of some of these people is a Japanese sweetpotato variety grown on

ally rose from $3.80 to $5.15 bettering the lives of laborers, but raising theabout 200 ha (about 500 ac) in California and called Kotobuki, which has lighthourly wage farmers must pay by 36%.

yellow, dry flesh.

In the case of the primary USA crops such as grains, production area islarge enough to justify mechanization research to drastically reduce labor

In any case, about 95% of USA sweetpotato production is of orange-fleshedvarieties.

costs. Sweetpotato is such a minor crop that only a few hundred machines of

The growing year begins in February or March when seed sweetpotatoes

any particular purpose would saturate the market, restricting the profitability

are removed from storage and planted in sprouting beds. A 1 m (39 in) widefor developing such machines. Further, the planting of sweetpotato slips andharvesting of the tubers have proven somewhat complicated to mechanize.
Ideally, machines designed for other crops would be used for sweetpotato, but
this still entails some degree of redesign. One successful pattern is for agricultural experiment stations to work with farmers in designing a machine, thenturning machine production over to a private firm.
16

An eight-row sweetpotato planter at rest inLouisiana. A tractor pulls the planter mannedwith 16 laborers who insert cuttings into themachine for automatic planting. (Photo courtesyof Dr. Don LaBonte, Louisiana State University)

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shallow ditch is prepared in which disinfected sweetpotatoes are placed, thensweetpotato is propagated vegetatively, viruses and the mutations which socovered with about 8 cm (3 in) of soil. This is covered with black plastic sheet-easily occur in sweetpotato tend to accumulate over time. Research is needed

ing to warm the soil. When sprouts begin appearing, the sheeting is removed.

to prevent these effects from adversely affecting the crop.

Some farms mechanically trim the sprouts to an even height to make themstronger and easier to mechanically transplant.

Insect pests and weeds are a farmer’s worry. Major pests include sweetpotato weevil (Cylas formicarius elegantulus Summers), banded cucumber bee-

Sweetpotato cuttings are planted during May and June. Most farms cut thetle (Diabrotica balteata Leconte), white grubs (Phyllophaga spp.), whitesprouts by hand, but by using a mechanical cutter five or six workers can dofringed beetle (Graphognathus spp.), wireworm (Conoderus falli Lane), andthe work of 100, cutting 420,000 cuttings in four hours.

sweetpotato flea beetle (Chaetocnema confinis Crotch). Due to sweetpotato’s

Using a six-row planter, 13 workers can plant 4.7 ha (12 ac) during an eight-

minor crop status, chemical companies are reluctant to develop agricultural

hour workday with 30,000 cuttings per hectare (2.5 ac). A planter moves atchemicals specially designed for it. Therefore one strong emphasis of sweet-

about 1.2 km per hour (0.7 mph) allowing the planting of one cutting per row

potato breeding is creation of varieties resistant to the primary pests, sweet-

per second.

potato weevil and banded cucumber beetle.
Weeds troublesome to sweetpotato farming include sedges such as Cyprus
esculentus L. Only one herbicide is widely available for sweetpotato cultivators,

Diseases and Pests
Present-day varieties of sweetpotato have been bred to be disease resistant,making cultivation easier than in the past. The possibly detrimental effect ofviruses on yield and quality is currently being researched, and use of virus-

so research is underway to create herbicide resistant varieties allowing use ofherbicides commonly used for other crops.
In any case, some research is also being done on pesticides or herbicides
specifically designed for sweetpotato cultivation.

free cuttings is increasing.
Until now, viruses were not considered a serious problem for sweetpotato
growers. But it is now recognized that viruses can reduce yield and cause poor

Harvestproduct appearance. They may also play a role in causing the high carotene

Before harvesting during August to November, farmers mechanicallyvarieties popular in the USA to mutate into a low carotene product. Since

remove vines from the ground. A two-row harvester using 14 workers can harvest about 1.5 ha (3.7 ac) during an eight-hour workday. A typical 120 ha (300ac) sweetpotato farm uses three two-row harvesters to harvest about 5 ha (12ac) per eight-hour workday, or about 25 ha (62 ac) per five-day workweek, tofinish harvest in about five weeks.

A four-row harvester at work inLouisiana using 23 workers to harvest 5 ha (12 ac) per day. Sweetpotatoes are graded, and put directly
by conveyor belt into 360 kg (800 lb)
crates for transport to curing sheds.
(Photo courtesy of Dr. Don LaBonte,
Louisiana State University)

18

A four-row harvester using 23 workers can harvest about 5 ha (12 ac) during an eight-hour workday. These are normally used on 200 ha (490 ac) or larger farms. Sweetpotatoes are graded, and put directly by conveyor belt into 360
kg (800 lb) crates for transport to curing sheds by forklift.
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To provide the same growing season for an entire crop, fields to be harvest-

the largest peak at Thanksgiving (fourth Thursday in November) and a small-ed earliest are planted earliest. A large farm may therefore spread planting

er peak at Christmas (December 25). Best grade sweetpotatoes, US #1, fetch

over as much as six weeks.

about $11 per 18 kg (40 lb) box. These must be nicely shaped with a 5 to 9 cm

A goal of the USA sweetpotato breeding program is to create varieties suited(2-3.5 in) diameter and 8 to 23 cm (3-9 in) length. Babyfood and some otherto mechanical harvesting that produce a uniformly sized marketable crop.

processors use mostly large sized sweetpotatoes paying about $7 per 18 kg box

This would make grading less labor intensive thus reducing labor costs, andfor marketable potatoes larger than US #1s. Canners pay about $2 per 18 kg

yielding a larger percentage of marketable crop which would provide farmers

box for misshapen or damaged US #1s, or those 2.5-5 cm (1-2 in) in diametermore income.

and 5-18 cm (2-7 in) in length. Outside the September to December sweetpotato season market demand is low so even the best grade potatoes fetch only $5

Postharvest
One purpose of curing is to heal sweetpotatoes bruised during harvest toto $6 per 18 kg box. The USA government does not subsidize sweetpotatoes,
so market prices vary widely during a year.

help them store better. This three to five day process of keeping the harvest at

The total retail value of USA sweetpotato sales is estimated at $350 million

27 ℃ (80︒F) and 85-90% humidity also yields a sweeter product. Following cur-for 1997. About 60% or more than $200 million of this went to the farmer, withing, the crop is stored at 16 ℃ (60︒F) with 85-90% humidity.

the rest going to processors, shippers, retailers, and so on.

According to market demand, sweetpotatoes are brought out of storage,

Canned sweetpotatoes, babyfood, and puree for pie account for almost all

washed, and shipped in 18 kg (40 lb) cardboard boxes. Rhizopus soft rot

USA sweetpotato processing. Processors include Gerber, Heinz, Beech Nut,

(Rhizopus stolonifer (Her. ex Fr.) Lind) is a worry at this point since it canand so on for babyfood; Bruce Foods for canned and flakes; and Allen Canningspread through a box spoiling the sweetpotatoes. To reduce the use of fungi-

for canned. Sweetpotato chips began appearing in some regions from about

cides, varieties strong against soft rot are being bred.

1995.

Shipment of sweetpotatoes is highest from September to December, with

The 1997 USDA Census reported farmers’ average sweetpotato yield was 17
mt/ha (7.4 t/ac). Of this, 60 to 70% is suitable quality for the fresh market
which returns the highest prices. To achieve best quality yields, with somevariation due to variety and so on, sweetpotatoes are best harvested 90 to 120
days after planting the cuttings. A farmer can break even on his/her investment by receiving an annual average of $5 to $6 per 18 kg (40 lb) box.

Some 30 to 40% of the USA sweetpotato harvest is processed, mostly canned. For canning, the potatoes
are steamed, peeled, and often flavored. A 450 g (1 lb) can sells for about $1. Bruce Foods (left andabove) and Allen Canning (above right) account for most of the canned market. (January 1999)

20

Reference:
LaBonte, D. R. and J. M. Cannon, “Production and Utilization of Sweetpotato in
the United States,” Proceedings of International Workshop on Sweetpotato
Production System toward the 21st Century, edited by Dr. Don R. LaBonte, Dr.
M. Yamashita, H. Mochida, Kyushu National Agricultural Experiment Station,
Miyakonojo, Miyazaki, Japan, March 1998, pp. 29-32.

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Research

National Sweetpotato Collaborators GroupThe National Sweetpotato Collaborators Group is a network for informationexchange among researchers established in 1939. A chief motivation for theestablishment was dissatisfaction with how sweetpotato varieties of the time
were weakening against disease. It was decided to begin a breeding program
to create improved varieties rather than continuing the traditional inefficientmethod of selecting favorable new varieties through natural mutations. In(left)
Dr. Mike Cannon, Resident Director of the
Sweetpotato Research Station associatedwith Louisiana State University, the only US
station devoted solely to sweetpotato.
(Holding Beauregard.)
Photo, courtesy of Dr. Mike Cannon,
appears in Louisiana Agriculture, Vol. 40,
No. 4, Fall 1997, the magazine of theLouisiana Agricultural Experiment Station.

1937, Dr. Julian Miller and others at Louisiana State University had succeededin getting sweetpotato to flower and bear viable seed, something that happens
naturally in tropical areas, but a challenge to make happen in temperate ones.
Two years later, this proved to be a key technology spurring the formation of
the Collaborators by Miller and fellow researchers.
onset of the Great Depression in late 1929, US acreage increased to a historical(above)Louisiana Agriculture special sweetpotato
issue, Fall 1997. (See also “Sweetpotato
Packing-Box Art” <p. 5>)high of 429,000 ha (1.06 million ac) in 1932. Sweetpotato was especially impor-products for transport to remote locations, drying techniques were researched.

tant as a food source for the Southern rural poor, another reason spurring the

Additionally, high starch varieties were bred. At the time, the starch was used

Collaborators’ formation.

in the food, as well as textile and other industries.

In 1912, 85% of US sweetpotato acreage was in 12 Southern states. With the

The Collaborators were first comprised of officials from the US Departmentof Agriculture and researchers of agricultural experiment stations attached toIn 1960, Centennial, a variety newly-bred in Louisiana was announced.
Centennial was to become the mainstay variety for the next 20 years or so.

Southern state universities. With time, membership expanded to include

Between 1969 and 1989, 29 new varieties were released in the US. Among

researchers from outside the South, members from industry, and so on. In

them, Jewel, released by North Carolina in 1969, was to dominate 80% of pro-addition to sweetpotato breeding, the Collaborators’ areas of interest expand-duction by 1989.

ed to include processing, mechanization of cultivation, storage, physiology,
entomology, and so on.

Most of the varieties released between 1969 and 1989 were high in carotene,
giving them orange flesh. But three releases had white or yellow flesh, though

During World War II, research was conducted into how best to process

none are widely grown today. Rojo Blanco, released by Alabama in 1977, has

sweetpotato for consumption by the military. To best preserve sweetpotato

deep red skin with white flesh, which is dry when cooked. Sumor, released in

2223さつまいも英語版8/16 06.3.23 4:28 PM ページ 241987 by South Carolina, has yellow to light brown skin with white to yellow

The National Sweetpotato Collaborators Group and Sweetpotato Council offlesh. It is not very sweet, resembling a potato when baked. White Delite was

the United States, Incorporated, maintain close ties. The Council members are

released in 1987 by North Carolina. With purplish pink skin and pale yellow

primarily sweetpotato growers, processors, and distributors. However, one

flesh, it has superior mouth feel.

goal of both groups is to increase US sweetpotato consumption.

Currently, US sweetpotato research is done primarily at experiment stations

The Collaborators also have international cooperation with the International

associated with North Carolina University, the Sweetpotato Research Station

Potato Center (CIP), the International Society for Tropical Root Crops, and so

associated with Louisiana State University, and the US Department of

on. International exchange of sweetpotato varieties and information enhances

Agriculture Vegetable Laboratory in South Carolina. Facilities corresponding

the production of improved varieties.

to these in Japan are the Laboratory of Sweetpotato Breeding at the Kyushu
National Agricultural Experiment Station (Miyazaki Prefecture), and the
Sweetpotato Breeding Laboratory at the National Agriculture Research Center(Ibaraki Prefecture).

Reference:
Jones, A., J.C. Bouwkamp, editors, Fifty Years of Cooperative Sweetpotato
Research,1939-1989, Southern Cooperative Series, Bulletin No. 369, Louisiana,
USA, April 1992.

The US Department of Agriculture maintains its collection of sweetpotato
varieties for breeding and preservation purposes at its germplasm collection at
the University of Georgia (Griffin, Georgia). In May 2000, there were morethan 600 varieties available.
The Collaborators are a volunteer network. The group’s headquarters
change according to which member is selected contact person. Annual membership is five dollars which is primarily used to publish the transactions of theannual meeting using the inexpensive services of the contact person’s associated university. Sweetpotato research is done primarily at the state level, or
through the US Department of Agriculture, but the Collaborators help facilitate information exchange among these groups.
Many of the Collaborators use research money from the US Department ofAgriculture, and their projects can be seen on the Internet.
The Collaborators are a part of the Southern Region of the American
Society for Horticultural Science which is affiliated with the Southern
Association of Agricultural Scientists. The Collaborators’ annual meeting isheld in conjunction with these other two organizations in late January or earlyFebruary, rotating among 13 Southern US states.
24■National Sweetpotato Collaborators Group Contact Person:
Dr. Wayne J. McLaurin
Extension Horticulture Department
University of Georgia
Athens, Georgia 30602-0002, USA
E-mail: wmclauri@arches.uga.edu■Management of the Sweetpotato Council of the United States, Incorporated, isbeing reorganized at this time (July 2000). Alternatively, the largest producing
sweetpotato state can be contacted at:
Sue Johnson-Langdon
North Carolina Sweetpotato Commission, Inc.
1327 N Brightleaf Blvd #H
Smithfield, North Carolina 27577-7263, USA
Telephone: (919)989-7323
Fax: (919)989-3015
E-mail: ncsweetsue@aol.com
Website: www.ncsweetpotatoes.com
25

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shows three CCOF-certified farms growing 14 ha (35.5 ac) of sweetpotatoes

Organic Farming of
Sweetpotatoes(April 2000).
At the request of individuals and groups concerned with improving theorganic food industry, the Federal Organic Foods Production Act was passedby the US Congress in 1990 to initiate the setting of national standards. The

The United States federal government is in the process of developing

Act charged the United States Department of Agriculture (USDA) with prepar-

national standards for organically produced and processed food. This is in parting a regulation stipulating national standards in detail, and also provided thatto meet the needs of a growing number of consumers, growers, and business-an advisory board, the National Organic Standards Board be formed to advise

es that feel organic produce is healthier, and kinder to the environment to

the USDA. The 14 members represent different segments of the organic foodgrow than the non-organic alternative.

industry, and primarily advise the USDA Secretary concerning what sub-“Organically grown” implies the use of natural fertilizers and growing meth-stances should be permitted for producing and handling organic food. As ofods to produce a healthy crop free of pests. One may even say that before theSpring 2000, the National Organic Program (NOP) is in its final stages of for-era of artificially produced fertilizers and pesticides that farming methods

mation with comments being received from the public concerning the revised

were implicitly organic. Likewise, the farmers in the world today who areproposed rule.

unable to afford artificially produced fertilizers and pesticides could be said tobe growing organic crops.

In accordance with opinions received from the public, among the productsthat will not be permitted to be labeled as organic under the NOP are geneti-

In 1930s England, the agricultural scientist Sir Albert Howard advocated thecally modified organisms, irradiated food, and food grown with sewage sludge.

use of natural fertilizers over artificial ones. This is said to mark the beginning

It is hoped that the NOP will reflect international organic food standards inof modern organic farming.
The US organic food industry, which began in the late 1940s, expanded
more than 40-fold during the decade beginning 1986 so that 1996 sales reached$3.5 billion.
In the USA there is currently a patchwork of organic farming standards withorder to facilitate trading of organic foods in the international marketplace.
References:
National Organic Program
www.ams.usda.gov/nop/
California Certified Organic Farmers
www.ccof.org/index.htm

some states having regulations, and others none. Even among states with standards, the degree of strictness varies. There are also organic farming organizations that set their own standards for members.
California, the leading US agricultural producer, formed an organic farming
standards law in 1990. The organization California Certified Organic Farmers(CCOF), which initiated the formation of a state standard, had previously beencertifying its own members following its founding in 1973. The CCOF web site
26

At Thomas Packing Plant in Livingston, California. The author
with area sweetpotato farmers Tom Nakashima (organic grower) (L) and Gary Hamaguchi (R). The upper three sweetpotato
boxes are labeled as organically grown (non-Nakashimabrands). (January 1997)27

さつまいも英語版8/16 06.3.23 4:28 PM ページ 28

At the international symposium “Sweetpotato Technology for the 21stCentury,” held at Tuskegee University (Alabama) in June 1991, it was declared

Sweetpotatoes

What’s in a Name?
Suitopoteto is the Japanese pronunciation of “sweetpotato,” but this namein Japan refers to a common confection made with that tuber as the main ingredient. Made from mashed sweetpotato, sugar, butter, and so on, it is baked inthat “sweet potato” should henceforth be called “sweetpotato” to emphasizethat it is a tuber in its own right, not a “sweet” potato.
Reference:
Schultheis, Jonathan R., L. George Wilson, “What is the Difference Between
a Sweetpotato and a Yam?”, horticultural information leaflet 23-A, North
Carolina Cooperative Extension Service, North Carolina State University,
revised September 1993.

small, individual, sweetpotato-shaped portions to serve with tea.
There are few interesting expressions in English using sweetpotato compared to Japanese where invoking that tuber’s name carries a negative connotation. However, “sweetpotato” in English is used to refer to the musicalinstrument “ocarina” due to its sweetpotato-like shape.
A greater variety of tubers is consumed in Japan than in the US. Looking at
the tubers consumed in both countries, potatoes are by far the most popular.
Next come sweetpotatoes. Other tubers popular in Japan, such as aroids (taro,
and so on) and yams, are consumed on a small scale in the US generally by certain ethnic groups favoring them. The tubers the majority of Americans arefamiliar with are limited to potatoes and sweetpotatoes. The “yams” that many
Americans think they are eating are in fact sweetpotatoes. True yams areunrelated to sweetpotatoes, but the name has been misappropriated as a namefor high carotene, moist flesh sweetpotatoes. “Sweetpotatoes” is used to refer
to lower carotene, drier flesh sweetpotatoes.

Declaration at the international symposium on “Sweetpotato
Technology for the 21st Century”, that “sweet potato” shallhenceforth be written as one word, “sweetpotato” to emphasize
it is not a “sweet” potato. From Tuskegee Horizons, Tuskegee
University, Alabama, USA, Fall 1991.

High-carotene sweetpotatoes are mistakenly called “yams” in the USA. The USDA requiresthat “yam” products be also labeled as containing sweetpotato to correctly inform consumers.

Sweetpotatoes preceded potatoes to Europe. Fifteenth century and later
European explorers came across sweetpotatoes in the Caribbean where they
were locally referred to as batata, leading to their being named patata in
Spanish or “potato” in English. When potatoes were subsequently better
received in Europe than sweetpotatoes, “potato” gradually came to refer topotatoes rather than sweetpotatoes, with the latter coming to be called “sweet”
potatoes.
28

Bruce’s Candied Yams label explains thecan actually contains sweetpotatoes.
January 1999.

Trappey’s Sugary Sam (Allen Canning) islabeled as both “yams” and “sweetpotatoes.”
January 1999.

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Most Common Ways of Eating
Sweetpotato
Of the eight G8 countries1) representing some of the world’s strongest

Baked Sweetpotato
Preparation
Sweetpotato is washed, buttered, and baked. It is best
to pierce it before it becomes soft to prevent rupturing.

economies, only two, the USA and Japan, consume much sweetpotato.
However, the tuber reigning in popularity in all eight countries is the potato.

Photography courtesy of the North Carolina Sweetpotato
Commission

Most of the sweetpotatoes consumed in the USA are high-carotene varieties, with annual per capita intake much lower than in Japan. Peak USA
consumption is on Thanksgiving Day (4th Thursday in November) whensweetpotato graces many tables along with turkey. Smaller peaks occur at
Christmas and New Years.
A common way of eating sweetpotato is eating it baked. It is often baked

Candied Yams

(serves 6 to 8)

Candied Yams is another popular dish.
There are many recipe variations, but a representative one follows:

along with whatever main dish is being prepared much as a baked potato
would be. Unlike potatoes, sweetpotato is eaten less often with beef than it iswith chicken, ham, or turkey.
The sweetness of a cooked sweetpotato will vary according to the time of

Ingredients
1.4 kg (3 lb)

year, and how quickly it is cooked. A sweetpotato freshly harvested in the fall,

1 tsp

butterto tastesalt, black pepper, paprika

2-3 Tbsand cooked quickly as in a microwave oven, will be less sweet. Using a cured

packed brown sugar or maple sugar

sweetpotato (all that is available in the winter, spring, or summer), and/or

2 Tbs

buttercooking the sweetpotato slowly such as baking it, will yield a sweeter product.

1/3 cupapple cider or waterThis phenomenon is due to how much the amylase enzymes in the sweet-

Preparation

potato are allowed to work. Starch is gradually converted by the enzymes to

Boil sweetpotato till not quite soft, peel, slice into quarters lengthwise. Layer

sugar as time passes after harvest. Also, as a sweetpotato cooks, heat caus-

in a 33 cm×23 cm (13 in×9 in) baking pan, sprinkling with seasoning for eaches the enzymes to more actively convert starch to sugar before they are final-

layer. Sprinkle on remaining butter, and the apple cider or water. Cover, andly destroyed by high temperatures. Slower cooking allows the enzymes morebake at 180℃ (350︒F) for about 45 minutes.

time to sweeten a sweetpotato than quick cooking.
1) G8 countries: Canada, France, Germany, Italy, Japan, Russia,
United Kingdom, United States.

30

sweetpotato

Seasoning for each layer:

Adapted from:
Rombauer, Irma S., Marion Rombauer Becker, Ethan Becker, Joy
of Cooking, Scribner, New York, 1997, p. 428.

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Sweetpotato Pie(serves 6)

Sweetpotato consumption is somewhat higher in the USA’s South than else-

Sweetpotato is often used interchangeably with pumpkin in USA cooking. Since strong flavorings are favored by many, it is often difficult to distinguish whether such dishes are made from sweetpotato or pumpkin.

where, and sweetpotato pie is one popular dish. Below is a recipe from theGone with the Wind Cook Book printed about the time the movie Gone with*

the Wind first played in theaters in 1939. The recipe is ascribed to one of theheroines, Melanie.

**

Sweetpotatoes are normally divided into two categories whether being
sold in supermarkets or introduced in cookbooks. One category, usually

Ingredients

called “yams,” refers to high-carotene varieties of sweetpotatoes that are

2 cupsmashed, cooked sweetpotato

sweet and soft when cooked. The other category is “sweetpotatoes” refer-

1/2 cupbrown sugar, firmly packed

ring to yellow- or white-fleshed varieties lower in carotene that are drier

1/4 tspsalt

than “yams.” Most cookbooks have recipes designed primarily for high-

1 tsp

cinnamon1/2 tspnutmegcarotene sweetpotatoes.

4

egg yolks

1/3 cupmelted butter or margarine

2 cupsmilk

4

egg whites

23 cm (9 in) unbaked pie shellThough about 95% of the USA sweetpotato crop is of high-carotene varieties, there are regions or ethnic groups preferring varieties lower incarotene. An important example is the Miami, Florida area where a significant proportion of the population is of Cuban origin. This area prefers lowcarotene sweetpotatoes of a genre referred to as boniato.

Preparation
1) Mix the sweetpotato, brown sugar, salt, cinnamon, and nutmeg.
2) Mix the egg yolks thoroughly, then mix into 1) with melted butter or margarine.
3) Mix milk with 2).
4) Whip egg whites until fluffy, then carefully fold into 3).
5) Pour into unbaked pie shell, bake at 220℃ (425︒ F) for 15 minutes, then at
190℃(375︒F) for 25 minutes till filling firms.

Regardless of the variety, sweetpotatoes areoften sold in USA supermarkets in two categories, “yams” (high-carotene), and“sweetpotatoes” (low-carotene).
(left)
Here, “sweetpotatoes” are selling for$1.50/kg (0.69/lb).
(center)“Yams” are on sale for $0.55/kg ($0.25/lb).

Adapted from:
Gone with the Wind Cook Book, Pebeco Toothpaste, Bloomfield, New Jersey,
USA, ca. 1939, p. 41.

32(right)Bagged and individual onions.
(Lake Oswego, Oregon. January 1999)

33

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Sweetpotato in Literature

The Yearling and Sweetpotato Ponebake about 45 minutes at 180℃ (350︒F), sprinkling the brown sugar and cinnamon over the top at the end of the first 25 minutes.

The home of US sweetpotato cultivation is in the

Simple Sweetpotato Pone

South. The novel The Yearling, written in 1938, cen-

It is more likely that what the Baxter family ate in The Yearling was a thickters on the Baxters, a poor family that lives in rural

sweetpotato pudding simply made as described by the author, Rawlings,

Florida, and consumes sweetpotatoes three meals per

below:

day for about half a year from the November harvest.

Ingredients

The Baxters often ate baked sweetpotatoes, but

2 cups grated sweetpotato“sweetpotato pone” was a special treat. This dish is

2 Tbs flour

bake in a shallow pan at 150℃(300︒F)

mistakenly translated as “sweetpotato bread” in a

3 Tbs grease from fried white bacon

until firm and slightly brown.

Japanese translation of the novel, though it is actually

1/2 tsp baking soda

a sweet dessert. Sweetpotato pone is a Southern dish which varies by region.
Below is a recipe from The Yearling’s author Marjorie Kinnan Rawlings’ Cross
Creek Cookery, named after a rural Florida area where she resided.

Preparation
Mix ingredients thoroughly, and1 cup homemade cane syrup
enough water to make a thin mixture
The sweetpotato pone recipes introduced by Rawlings above call for thehigh carotene, sweet, sweetpotato varieties most popular in the US. Rawlings
does not write clearly in The Yearling what variety of sweetpotatoes the

Ingredients

Baxters were growing, but one may surmise that since they were a major part2 1/2 cups grated raw sweetpotatoesof the Baxter diet, they would likely have been a variety low in sweetness.

1 cup molasses
2 eggs2 cups rich milk
1 Tbs melted butter
1 tsp ground ginger or grated orange rind
1 Tbs brown sugar
1/2 tsp powdered cinnamon

References:
Rawlings, Marjorie Kinnan, The Yearling, Scribner Classic
Collier Edition, reprint of 1938 edition, New York, 1986, pp. 12,
118, 143, 196, 215, 264, 265, 301, 308.
Rawlings, Marjorie Kinnan, Cross Creek Cookery, Charles
Scribner’s Sons, New York, 1942, pp. 183-185.

Preparation
Add the molasses, well-beaten eggs, milk, melted butter and ginger or orange
rind, in order, to the grated potatoes. Turn into a well-greased baking pan and34

Rawlings, Marjorie Kinnan, The Yearling, Scribner
Classic Collier Edition, reprint of 1938 edition, New
York, 1986. Drawn by Edward Shenton.

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The high-carotene sweetpotatoes preferred in the USA provide a different

Eating Out

Sweetpotato at the Restaurant

appearance and mouth feel compared to the low-carotene, dry-fleshed sweetpotatoes popular in Japan. Also, there is a preference among USA cooks tocover up the sweetpotato’s natural taste with cinnamon and other strong
spices.

Sweetpotato is not a common daily food in the USA. However, it has recent-Though sweetpotato has been available only in limited USA restaurants, anly begun appearing on more restaurant menus due to the innovation of certain

exception is Thanksgiving, the fourth Thursday of November. This day cele-

restaurant chains. Until recently, about the only type of restaurant that served

brates a successful harvest had by 17th century Pilgrims eking out a living

sweetpotato with any regularity was one specializing in soul food, dishes tradi-with the help of Native Americans in what is now the Northeast USA. Today’s

tionally eaten by African-Americans, especially those from the South. Even so,

Thanksgiving menu often includes various foods native to the Americas:

to locate such a restaurant one usually had to search for an urban area withturkey, sweetpotato, cranberries, and so on. Similar to New Years in Japan, rel-some concentration of African-Americans.

atives gather together to feast on foods special to Thanksgiving. For those

Soul food evolved from the humble foods of rural Southern AfricanAmericans. As they moved to big cities throughout the USA, a nostalgia for ataste of home led to humble foods evolving to meet modern tastes, and soul
food became one point of identity for African-Americans.

unable to celebrate with relatives, many local restaurants serve Thanksgiving
fare, including sweetpotatoes, during that season.
In my youth a few decades ago, turkey, sweetpotato, and cranberry were all
still thought of as primarily Thanksgiving foods, and were not available year-

Sweetpotato tends to be favored more in the South than in other areas,round nationwide. The arrowroot that appears in Japanese New Years cooking

regardless of race or ethnicity. The warm climate there is better suited for rais-

is similar in this regard as it disappears from the market following the holidays.

ing heat-loving sweetpotatoes than potatoes which prefer a cooler climate.

However, the turkey and cranberry industries improvised on how to adjust

Favored ways of eating sweetpotato there include baked, various kinds oftheir products so they now appear in a variety of forms year-round. First need-desserts, and so on.

ing a change was the autumn/winter holiday-use only image. Cooking a large

Meals at soul food restaurants tend to be centered around hamburger,

turkey for a big family gathering takes much of a day, so the turkey industry

chicken, catfish, and so. Individually run restaurants have been more common

began marketing turkey parts, as well as processed products, that arethan soul food chains, so there is menu variation depending on the restaurant

designed to be easily consumed year-round.

one chooses.

Similar to turkey, cranberries were also long associated primarily with theThompson’s Point of View, a soul food restaurant in Seattle, Washington,Thanksgiving holidays as an accompaniment to turkey. It was basically sold as

was where I ordered a catfish dinner some years ago. Customers could chosefrozen berries for home processing, or sold as canned relish or gelled juice.

two vegetables to go with the main dish, so I enjoyed candied yams and black-

The cranberry industry has succeeded in breaking its Thanksgiving-only

eyed peas. A large cornmeal cake rounded out the meal, and the other sweet-

image through creative marketing of various juices containing their product,

potato item on the menu, pie, was a suitable ending.

and of craisins, dried cranberries that the industry encourages consumers to

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use as they would raisins. Sweetpotatoes remain locked in to a strong “food for
Thanksgiving/holidays” image.

There are also more independent restaurants regularly offering sweetpotato. Hays, Kansas, a college town with about 20,000 residents, has a restaurant

As the chart “USA Agricultural Farm Income” (p. 9) shows, the value of the
US sweetpotato crop is less than that of either cranberries or turkey.
However, at least one restaurant chain, Roadhouse Grill, has introduced
sweetpotato as a regular item on its menu which mainly centers around steak.
With the first store opening in 1993 in Florida, the chain now has about 80
stores in 10 states, mostly in the South. Once related to this chain, there arealso three Original Roadhouse Grill’s in Oregon with a similar menu.
The Grill is an inexpensive family restaurant. Near the register in theoffering baked sweetpotato as a side dish choice with steak dinners. Available
only on weekends, sweetpotato is flavored with brown sugar and butter.
Offered since about 1995, about half of customers choose sweetpotato overpotato. Other Hays restaurants have begun similar offerings.
References:
Macintosh, Elaine, American Food Habits in a Historical Perspective, Praeger
Publishers, Westport, Connecticut, USA, 1995, USA, p. 82.
Thomas, Gertrude I., Foods of Our Forefathers, F.A. Davis Co., Philadelphia,
Pennsylvania, USA, 1941, p. 50.

restaurant I entered was a large barrel of peanuts. Waiting to be seated during
peak times, customers are encouraged to munch on peanuts and throw theshells on the floor. To reach a table that opens up, one must crunch across thefloor atop these shells. While waiting for one’s order, there are more peanuts
to snack on at the table. Children especially delight in littering the floor in a
way they could never do at home.
Different from other steak houses,
the Grill offers baked sweetpotatoes as
one of its side dish choices for dinners,

A fast-food restaurant with sweetpotato fries on its menu.
BurgerVille USA, Vancouver, Washington. January 1999.

along with potatoes. My sweetpotato
came seasoned with brown sugar andcinnamon. There was also sweetpotato
pie offered for dessert.
Buffets, Incorporated, also offers
sweetpotato in some of its chain restaurants. Buffets offers candied yams (asweetpotato dish) on the Sunday menu
of two of its buffet-style chains,
Country Buffet and Home Town
Buffet.
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The Original Roadhouse Grill, Portland, Oregon.
The author’s brother, Gary, holding vegetable andbeef shish kebabs on pilaf (front), and a baked
sweetpotato with light-yellow flesh (back). August
1998.

Baked sweetpotatoes with orange flesh (back) served with beef steak(left) and asparagus (right) at Best Western, Hotel Acadiana(Lafayette, Louisiana). Sweetpotato Council of the USA, Inc., banquet. January 1999.

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USA Sweetpotato Festivals
Festival Name

Sweetpotato Festivals
There are a variety of agricultural festivals held in the USA ranging fromlarge to small. A common pattern is for an agricultural area’s main crop toserve as the festival theme with the area’s other crops also sharing some of thelimelight.

1)

Place (1990 population)

Date held

Year started

East Texas Yamboree

Gilmer, Texas (5,000)

mid-October

1935

Georgia Sweetpotato Festival

Ocilla, Georgia (3,000)

end of October

1961

Louisiana Yambilee

Opelousas, Louisiana (18,000)

end of October

1946

National Sweetpotato Festival

Vardaman, Mississippi (1,000)

November

1974

North Carolina Yam Festival

Tabor City, North Carolina (2,000)

end of October

1950s

Yamboree Festival

Livingston, California (7,000)

end of August

1980s1) Yamboree and Yambilee are plays upon the word “yam” combined with “jamboree,” and“jubilee.” “Yam” in the USA usually refers to sweetpotato varieties having a deep-orange flesh.

Though sweetpotato is a minor USA crop, there are nonetheless a numberof sweetpotato festivals. Introduced below are six that have come to theauthor’s attention. Each is held in a small town where agriculture is important,and sweetpotatoes are (or used to be) an important crop. The festivals aremeant to draw tourists, as well as demonstrate community pride. Though thefestival programs vary, many feature sweetpotato in exhibitions, cooking competitions, Miss Sweetpotato Contests, direct sales of the tuber or products
made from it, and so on.
According to community enthusiasm, a festival may have a long history, dieout, be revived, have its date or name or contents changed, and so on. The festivals introduced below are those known to the author who may have unknowingly left out other important ones.

Louisiana Yambilee. The 1978 Yambilee Queen
Renee Bryant with the successful bidder of theauction for the first place winner of the fresh sweetpotato competition. Photo courtesy of L.J.
Duplechain, former Executive Director, Louisiana
Sweetpotato Commission.

North Carolina Yam Festival. Deborah Hathaway, organizing committee member, wearing a festival T-shirt(January 1999).

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California Yamboree Festival. A 1992 sceneof a sweetpotato pie booth. Photo courtesy of
Velma Duell McConnell and the Livingston
Chamber of Commerce.

East Texas Yamboree. The 1996 Yamboree Queen
Leslie Erin Glaze (center) is surrounded by her court.
Photo courtesy of Velera Jones and the Gilmer
Chamber of Commerce.

Reference:
Vardaman Sweetpotato Festival Committee (Mississippi), The Sweetpotato Cookbook,
Enjoy Nutritious Sweetpotatoes with Vardaman Sweetpotato Recipe Collection,
Morris Press, Kearney, Nebraska, USA, 1996.

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President George Washington
Efforts have been made to preserve President
George Washington’s home, Mount Vernon(Virginia), as it was when the first US president
lived there two centuries ago. In the kitchen garden are grown the vegetables cultivated then,which include sweetpotatoes.
The cookbook of Mrs. Martha Washington
remains, which contains recipes handed downfrom her ancestors. This custom of upper class
English homes was brought by their immigrant members to North America. A
daughter would copy down recipes and household hints from her mother’s
own handwritten cookbook. Also included might be recipes from friends, relatives, servants, and so on. A young woman would bring along the book as partof her trousseau upon marriage. The cookbook of Martha Washington seems
to have been written by the mother of her first husband, and therefore datingfrom the last half of the 17th century. The contents relate mostly to English
cooking.
In Martha’s cookbook appears a recipe for a meat pie with potatoes. At thetime, “potato” still referred to both potatoes and sweetpotatoes, but ingredients such as orange, grapes, and other fruits, indicate that this potato is most
likely sweetpotato. Unfortunately, it is not evident how the Washingtons
favored consuming sweetpotatoes, or how often.

George Washington Carver andTuskegee University
George Washington Carver was an agricultural chemist who researched thepotential of sweetpotatoes and peanuts more than 40 years at what is today
Tuskegee University in Alabama. He was born as a slave about 1860. Freed
after the end of the Civil War, Carver worked his way through school attaining
a master’s degree before being named director of agricultural research at
Tuskegee Normal and Industrial Institute in 1896.
The Institute was founded in 1881 to train African-Americans how to be economically independent through learning manual and agricultural skills. The
first principal was Booker T. Washington. The Institute gradually evolved into
what is today Tuskegee University. Open to all applicants today, the student
body continues to be primarily African-American.
In the late 1800s, discrimination against African-Americans was an impediment for their developing their potential. Principal Washington believed
African-Americans could better improve their situation through education
rather than political confrontation against the white majority. Carver was inagreement with this principle since it allowed African-Americans to improvetheir economic situation in society.
During Carver’s time, agriculture was still a prevalent occupation. There
were many poor African-American farmers in the Tuskegee area. Until his
death in 1943, Carver not only taught students, but also set up an extension
program to help area farmers improve their farming techniques, and toencourage them to grow peanuts, sweetpotatoes, and other crops for improving the soil, balancing their diet, and providing them with cash crops.

Reference:
Hess, Karen, transcriber and annotator, Martha Washington’s Booke of Cookery,
Columbia University Press, New York, 1981, pp. 84-87, 447-463, 475-476.

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Carver promoted the growing of peanuts not only because they were nutritious, but also because they returned nitrogen to the fields. At the time, cotton,
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which was extensively grown in the South, had exhausted the fields. So

Museum at Tuskegee University, set up in 1938 to honor the famous man who

Carver brought his scientific knowledge to poor farmers to improve their farm-taught and researched there. The Museum became a national historic site ining techniques and raise their living standards.

1977, and currently has displays concerning Carver’s life and research, as wellThrough Carver’s persistence, peanuts became a major crop in the South.
By the 1940s, peanuts were second only to cotton in economic importance.

as introducing Tuskegee’s history.
Peanut and sweetpotato research continues at Tuskegee University. The

Carver developed a number of products from peanuts and sweetpotatoes.

National Aeronautics and Space Administration (NASA) has designated

The more than 300 products from peanuts included cheese, peanut milk, soap,

Tuskegee as the site for researching how best to grow and utilize these twoplastic, and more. From sweetpotatoes he made flour, vinegar, rubber, ink, andcrops in outer space. Subsequently, in 1991 an international symposium

more than 100 other products.

“Sweetpotato Technology for the 21st Century” was held at Tuskegee.

It is difficult today to understand the full value of Carver’s research consid-

NASA’s goals for space agriculture concern reducing the amount of cargoering the discrimination that was rampant against African-Americans in his

required to take into space. By astronauts growing some of their own food,day. He was beloved by the white majority since he was not an advocate forthese crops would help convert astronauts’ exhaled carbon dioxide into oxy-political change in the status of African-Americans. He also was active far awaygen, help recycle waste water, and so on. Advantages of including sweetpota-from the white majority, preferring to conduct his work in the South among a

toes as a crop for space include its being able to withstand environmental

largely African-American population. Whites considered him to be a modelstress, having few parts that are inedible, ability to produce a large number ofAfrican-American.

calories in a short time in a small space, and so on.

Carver seems to have been looked at askance by those African-Americans

On the fourth Thursday of November, Thanksgiving Day, in the USA, many

who were strongly advocating “African-American”-

families consume sweetpotatoes along with turkey and other foods of that day.

white equality through political action. In any case,In 1997 there happened to be a NASA Space Shuttle flight in progress on thatafter his 1943 death, the US Congress declaredholiday. Though astronauts had taken along Thanksgiving food, one regretted

January 5, 1946 to be “Dr. George Washington

that there were no sweetpotatoes included. How long will it be before astro-

Carver Day.” Unfortunately, there seem to be few

nauts can enjoy sweetpotatoes on their menu?

today who remember this day. However, the South

Finally, a National Sweetpotato Information Center has been established atCarolina legislature in April 1998, following the

Tuskegee University.

lead of ten other states, revived the concept bydeclaring January 5 to be “Dr. George Washington
Carver Day” in that state.
Also, the site of Carver’s birth in Missouri was
declared a national monument the year he died.
Likewise, there is the George Washington Carver
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Prof. George Washington Carver,
Tuskegee University, Alabama,
renowned agricultural chemist who
researched the potential of sweetpotatoes and peanuts. 1930s photoused with permission from: National Park Service - George Washington Carver National Monument.

References:
Carver, George Washington, How the Farmer Can Save His Sweetpotatoes,
Bulletin No. 38, November 1936, Tuskegee Institute Press,Tuskegee, Alabama,
USA, 4th edition, 1937.
Hill, Walter A., Conrad K. Bonsi, Philip A. Loretan, editors, Sweetpotato Technology
for the 21st Century, Tuskegee University, Tuskegee, Alabama, USA, 1992.
Holt, Rackham, George Washington Carver, an American Biography, Doubleday,
Doran and Co., Inc., Garden City, N.Y., USA, 1943.

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