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Legumes, Nuts
& Seeds
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Legumes Peas Field Peas Garden Peas
Chickpeas Cajan Peas
Garden Beans Cowpeas
Soybeans Broad Beans
Lima Beans
Horse Beans
Velvet Beans Peanuts Lentils Lablab Forage Crops
Forage Legumes Alfalfa Clover Sweet Clover
Kudzu
Lespedezas Vetches Tree Legumes Algaroba
Carob Honey Locust
Misc. Tree Legumes Nuts High Fat Content Brazil Nut
Cashew
Nut Coconut
Hazelnut Hickory Nuts
Macadamia Nuts Pecan Pili Nut Pine Nuts Butternut
English Walnut
High Protein Content Almonds
Beechnuts Pistachio Nuts High Carbohydrate Content Acorns
Chestnuts
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Legumes rank next in importance to cereals as human food sources. They contain more protein than any other vegetable
and thus are akin to animal meat in food value. Fats and carbohydrates are also present. The proteins occur as small granules in
the same cells with the starch grains.
The high protein content is related to the presence on the roots of
many legumes tubercles that hold nitrogen-fixing bacteria. These bacteria are able to convert
atmospheric nitrogen into nitrates.
This augments the nitrogenous material available for the plants. The legumes belong to the family Leguminosae, which is noted
for having a special kind of fruit, a legume, which is a pod that opens along
two sutures when the seeds are ripe.
Over 11,000 species of legumes are known, and many are of importance
as industrial, medicinal or food plants.
They have been cultivated and used for food for centuries
worldwide. The seeds are of greatest
importance. As is the case with other
dry seeds, the low water content and impervious seed coats enhance their
value for long-term storage and increase their longevity. Legumes are easy to grow, they mature
rapidly and they are highly nutritious.
Not only are proteins abundant but also they possess minerals and
vitamin B. They are absolutely
essential in a vegetarian diet.
Before the discovery of potatoes, they constituted a greater part of
the food in Europe. Legumes have a
high-energy content and are particularly well suited for use in cold weather
or where physical exertion is pronounced.
The immature fruits also serve as food as demonstrated by garden beans
and peas.
Because all parts of the
plant are rich in protein, legumes are valuable as field and forage
crops. When plowed under they are an
excellent fertilizer and greatly increase the nitrogenous content of soil. The common pea, Pisum sativum, is native to
Southern Europe and has been cultivated since before the Christian era. Peas were well known to the Romans and
Greeks. However, it wasn’t until the
middle of the 17th Century that production became more widespread in
Europe. The earliest colonists
brought peas to America. Peas are
annual, glaucous; tendril bearing, climbing or trailing plants, with white or
colored flowers and pendulous pods.
Although originating in warm regions they thrive where there is a cool
summer and abundant moisture. The gray pea of Greece and the
Levant is thought to have given rise to Field Peas. They have colored flowers and angular colored seeds and are
very hardy, withstanding frost and altitudes up to 8,000 ft. Field peas are grown for seed that is used
for human consumption in the form of pea meal or split peas. They are also an excellent grain for
livestock. The plants are sued for
forage, silage and green manuring. Garden peas have white flowers and
round smooth or wrinkled seeds that are yellow or white in color. They contain more sugar than field peas
and the seeds are eaten green or are used for canning. For canning peas are usually harvested
with a mowing machine. Pea-cannery
refuse is a valuable livestock feed.
In some varieties the pods are fleshy and crisp and are consumed as
well as the seeds. Garden peas wee
used by Gregor Mendel in his experiments in plant genetics. Chickpeas (Garbanzo
Beans) Chickpeas, Cicer arietinum, are native to
southern Europe where they are still extensively grown. They are an important food in many parts
of Africa, Asia and Central America.
India has grown an amount that is equal to the sugar cane acreage of
the whole world. The plant is a branching,
bushy annual, which mature in 90 days.
It is well adapted to arid and semiarid regions. Chickpeas are the best legumes for human
consumption as the seeds are very nutritious. The early Egyptians, Hebrews and Greeks grew them. The sparse foliage is poisonous so the
plant cannot be used for forage. The
green pods are infrequently consumed and the seeds are used as a substitute
for and as an adulterant of coffee. Cowpeas, Vigna sinensis, are more closely
related to beans than to peas. They
are vigorous bushy or trailing summer annuals with curious, cylindrical
pendant pods. The plant continues to
grow if environmental conditions are suitable. The cowpea is a very old crop, probably originating in Central
Asia, although it has been grown in Southeastern Asia for over 2,000
years. It was introduced into the
tropics and subtropics of the world, reaching the West Indies in the 17th
Century and North America in the 18th Century. The seeds are used as feed for poultry and cattle, and they may
serve as a coffee substitute. The
main value is as a forage crop, as a cover crop to prevent erosion and as a
green manure. Cowpeas are important
in India, China and the southern United States. It is susceptible to frost and is confined to warm humid areas
in a sandy or loamy soil. This is a pigeon pea, Cajanus cajan, that was
first domesticated in Asia or Africa and is now widely cultivated in the
tropics and subtropics, especially in the East Indies, the West Indies and
India. There are many varieties. The plant is an erect shrub. Both the immature and mature seeds have
been used for human and animal food for thousands of years. In modern times it has been developed as a
forage crop and rivals alfalfa in importance. It is drought resistant, grows well in any kind of soil,
matures rapidly and in other ways is highly desirable. Beans Garden or kidney beans, Phaseolus
vulgaris, are indigenous to America.
They were probably domesticated by the Incas and were early used by
the Amerindians of both South and North America. In modern times the young pods (string or snap beans), the
unripe seeds (shell beans) and the dried ripe seeds are all used for human
consumption. The whole plant is used
for forage. Beans are low, erect or
twining annuals with small white or colored flowers, trifoliate leaves and
slender pods. They are grown as
either bush or pole beans and over 1,000 varieties are cultivated. Both groups have green-podded and
wax-podded varieties. The commercial
dried bean is of more recent origin.
It was first grown in 1836 in New York state. Much of the bean crop is canned. Even though beans will grow on a variety
of soils, a fertile soil, rich in lime, is required for a good yield. A warmer climate than for peas is
desirable, and crop rotation should be practiced. On large farms machines harvest the crop and the beans are
dried, stored and threshed before marketing.
The culls are fed to livestock and the straw is used for forage. Presently these beans are grown worldwide. Lima beans, Phaseolus limensis, are native to
Peru and Brazil and have been grown in South America for centuries. Originally a perennial they are usually
treated as annuals. Lima beans require
warmer weather and higher humidity than Garden Beans. The original types were pole beans, the
bush limas arising later as mutations.
Either green or dried beans are consumed and a large quantity is
processed. In addition to the large
variety there is a smaller form, the Sieva Bean (Phaseolus
lunatus), also native to tropical America. Other species of Phaseolus that are often
cultivated include the Scarlet Runner Beans,
P. coccineus that have a thickened root and ornamental flowers and the
Mung Bean, P. aureus. Mung beans were grown in India in ancient
times and are still an important crop.
The small oval seeds are highly nutritious and the green pods are also
consumed. There are over 100
varieties grown in China and other parts of Asia. The Mung Bean is grown in North America principally as a forage
plant. The Adsuki
Bean, P. angularis, is next to the Mung Bean in importance in
Manchuria and China; and the Rice Bean, P.
calcaratus, is widely cultivated in Southern Asia. Soybeans Soybeans, Glycine
max, are small, bushy, erect or prostrate annual plants that resemble the
cowpea. The crop is much easier to
handle for it does not become tangled, matures earlier and has a higher
yield, produces a better seed and can be threshed. The seeds all mature at the same time. The soybean is one of the oldest
cultivated crops. It was grown in
China centuries before the first written records in 2,838 B.C. It is indigenous to Southeastern Asia,
where over 1,000 varieties are grown.
Manchuria has led commercial production, followed by Korea, Japan,
China, Indonesia and North & South America. Soybean is the most important legume in Asia there it is
consumed fresh, fermented or dried and is used everywhere in the daily diet
to supplement rice. The seed is the
richest natural vegetable food known.
In tropical areas, especially Indonesia, soybeans are boiled and then
fermented by addition of a mold to yield a food known as Tempe. Soybean sauce, made from cooked beans,
roasted wheat flour, salt and ferment, is widely used. The flour, with a low carbohydrate and
high protein content, is an excellent food for diabetics. Soybean milk, extracted from the seed, is
used in cooking and is used as a substitute for cow’s milk. Soybean sprouts are a favorite food in the
Asian diet. The soybean has
ever increasing other uses worldwide.
It is an important aid to agriculture, a valuable commercial crop, a
good livestock food and the source of numerous raw materials for use in
industry. Soybean oil is an important
drying oil. Soybean protein is extensively
used to produce the foam liquid used for extinguishing oil fires and as the
source of a synthetic fiber, similar to casein fibers. Ever since the
1930’s soybean has assumed a position of great importance in the agriculture
of the United States. It is of
greatest importance in the North Central states, with Illinois producing over
50 percent of the total crop.
Soybeans are grown for hay, silage, and green manure, as well as for
the seeds, and hundreds of varieties are known. It can be grown under a variety of soil and moisture conditions
but requires a rather warm temperature and is susceptible to frost. Broad Bean, Vicia faba, is also called the Windsor Bean, Horse Bean
or Scotch Bean. It is grown as a forage crop as well as for the seeds that
furnish food for both humans and livestock.
The plant is a strong erect annual, 2-4 feet tall, with flat pods and
large seeds. It was cultivated in
prehistoric times and most likely is indigenous to Southwestern Asia or
Algeria. Over 100 varieties have been
grown, mainly in the Old World. The
broad bean was the only edible bean known in Europe before the voyages of
Columbus to America. It is an
important crop in England. Its growth
is encumbered by dry hot summers and thus is not a preferred crop in most of
the United States. It is sometimes
used as a cover crop, in crop rotation and for livestock fodder and silage as
well as for the seeds. Horse or Jack Beans, Canavalia
ensiformis, are indigenous in the West Indies and are now grown in almost
all tropical countries for their seeds.
The plants are bushy annuals with long sword-shaped pods that may
contain as many as 12 large beans.
The unripe seeds and pods are used for human food and the whole plant
serves for green forage. The plants
are hardy, drought-resistant and immune to most pests. They are grown principally in the southern
United States. Velvet beans, Stizolobium deeringianum, are
widely cultivated in the tropics for their edible seeds and for fodder. The plant is an annual herbaceous climber
that exceeds most other legumes in the rapidity and extent of growth. It has become of some importance in the
Southeastern United States. Peanuts, or Groundnuts, Arachis
hypogaea, are true legumes rather than nuts because the shuck is merely a
shell-like pod. The plant is a bushy
or creeping annual with the strange habit of ripening the fruit
underground. The peanut is indigenous
in South America but was early carried to the Old World tropics by the
Portuguese explorers and is now grown extensively in most tropical
countries. It was brought to Virginia
from Africa and is now one of the most important crops in the Southeastern
United States. There are over 20
different kinds of peanuts grown that differ in habit and the size of the
pod. The cultivation of peanuts is
quite complex. They require ample
warm sunshine and a moderate rainfall and can be grown successfully only
south of 36 deg. North latitude. A
sandy soil is preferred, although any but a low soil can be used. The soil must be friable so that the
ripening fruit can be buried and it must be well fertilized. During harvest the rows are plowed and the
plants are lifted out with forks, shocked and capped for cure. Later the fruits are removed, cleaned and
polished. The plants may be used for
forage, livestock feed or as soil renovators. The nuts or seeds are used for roasting or salting. In candy and for the preparation of peanut
butter. For the latter the seed coats
and embryo are removed and the nuts are roasted either dry or in oil, and are
then ground to a paste. Peanuts are
very nutritious. One pound yields
2,700 calories whereas one pound of beef furnishes only 900 calories. Nevertheless, some are allergic to peanuts
and must take precautions to avoid ingesting peanuts or their
derivatives. Peanut oil is important
food oil. The oil cake is fed to
livestock. The protein contained in
the nuts has been used in the manufacture of Ardil,
a synthetic fiber. Lentils, Lens culinaris, are some of the most
ancient of foods and also one of the most nutritious. The ancestral home is Southwestern Asia,
but they were introduced into ancient Egypt and Greece. Lentils are often mentioned in the
Bible. The plant is a slender,
tufted, many-branched annual with tendrils.
The pods are short and broad, with small lens-shaped seeds. The seeds are used principally in soups
and in East Indian cuisine mixed with rice and herbs. They are easy to digest, more so than
meat. These are produced in colors
that vary from gray to tan and red.
The plants have been used for fodder. Lablab, Dolichos lablab, is a bean-like legume
that is grown in many tropical areas.
The plant is usually a woody climber with a high yield of pods that
continue to bear over several years, but that may also be grown as an
annual. Both the pods and the seeds
are consumed, and the entire plant is used for hay and forage for horses and
cattle. The need for forage crops arose with the domestication
of animals. Initially wild grasses
probably were used, but other sources were then sought. These gradually became more numerous and
more varied. Today the extensive
cultivation of grasses and legumes as forage crops is principally the product
of European and American civilizations.
In addition to various cereal grasses and food legumes, many other
species have been grown entirely as forage crops with little or no value as
human food. Included are such grasses
as Timothy, Phleum pratense, Orchard Grass, Dactylis glomerata, Redtop, Agrostis alba, Brom
Grass, Bromus inermis, Johnson Grass,
Sorghum halepense, Tunis Grass, Sorghum
virgatum, and Sudan Grass, Sorghum
vulgare var. sudanense. Alfalfa, Medicago sativa, native to Southwestern
Asia, may have been the first cultivated forage plant. it was known to the Greeks, Romans and
Persians. It was introduced into China
and Europe and reached North America during the European colonization. Alfalfa has become the most important
forage crop grown in the United States and many new varieties were developed. It is especially abundant in Middle
Western and Western states. Alfalfa
is useful for pasture, hay and silage and for improving the soil. Dehydrated alfalfa or alfalfa mean is also
used, and alfalfa sprouts are used for human food. Other species of Medicago include Bur
Clover, M. hispida and Medic, M.
lupulina. Clover, Trifolium spp., is grown particularly in
the Northeastern and North Central united States. It is valuable in crop rotation and is often grown in mixtures
with forage grasses. Important
species are Red Clover, Trifolium pratense,
Alsike Clover, T. hybridum, Ladino or White Clover,
T. repens, and Crimson Clover, T.
incarnatum. Sweet clovers, Melilotus spp., have become
important forage crops since the beginning of the 20th Century. They are especially valuable for pastures
and for soil improvement. Most
production is centered in the Corn Belt of the United States. Both White Sweet Clover, Melilotus alba,
and Yellow Sweet Clover, M. officinalis, are grown. Kudzu Bean, Pueraria lobata, is a
drought-tolerant perennial legume indigenous to Japan and Eastern Asia. It was introduced into the Southeastern
United States in the middle 20th Century.
The plant has a long tap root and produces runners of 50-100 feet in
length. Kudzu yields good hay and
forage and was important in erosion control.
The pods can be used and a valuable starch is obtained form the large
roots. Gradually kudzu escaped into
the countryside and has begun to smother native vegetation. By the 21st Century it had attained a pest
status of very grave concern as few efforts to eradicate it or to reduce its
abundance have succeeded. Three species of Lespedeza of some importance in the
Southeastern United States are the annual Common Lespedeza, Lespedeza striata,
a Korean species, L. stipulacea and a perennial from China, L.
cuneata. These are beneficial to
soil conservation and for renewing exhausted soils. They furnish excellent hay and pasturage. There are a number of Vicia spp,
both native and introduced, that are used for forage, especially in the
coastal areas of the United States.
Two species of importance are Common Vetch, Vicia sativa, and
Hairy Vetch, V. villosa. They are mostly weak-stemmed, viny annuals
that are useful for cover, green manure and soil improvement as well as for
hay, pasture and silage. Livestock
find them very palatable. They are
frequently grown in mixture with small cereal grains. Tree legumes have come into prominence
as replacements for cereal grasses on eroded soils. A few species are excellent substitutes for maize, wheat and
other cereals in livestock feeding.
Some of the more important tree legumes are the following: Mesquite, also known as Algaroba
and Keawe, Prosopis juliflora, is native
to the West Indies, Central America and Mexico. The introduction of a single tree into Hawaii was followed by a
spread to the drier climatic zones of all the islands. It is considered a desirable species on
the islands. The flowers are a source
of honey and the pods and ground seeds are important livestock feed. Mesquite gives an enormous yield of 2-10
tons per acre depending on the local rainfall. It has been estimated that one acre of mesquite can produce
1,600 lbs. of beef, while one acre of corn or alfalfa produces only 450
lbs. Mesquite trees grow rapidly, are
drought-tolerant and can utilize arid, barren ground where other crops will
not grow. Cultivation of Mesquite has
extended to other parts of the world with similar climate. Another species, Prosopis glandulosa,
is better adapted to colder climates. The carob tree, Ceratonia siliqua, is native to
Syria but has been cultivated since ancient times in other Mediterranean
countries. Carob was the “locusts”
that were the food of John the Baptist and the Prodigal Son of the Bible
(Hill 1952). The large pods have
served as livestock feed for ages.
The tree is a small evergreen with glossy green foliage. It blooms in autumn and carries the young
fruit until late the following summer.
It does best in rocky dry soil.
Carob trees give a very high yield of pods. These contain 50 percent sugar and are often consumed directly
in the dried state. The ground seeds
yield a highly nutritious meal that can be added to bread. The pods contain a valuable gum known as Tragasol.
Although a handsome tree, the bloom gives an obnoxious odor and the
numerous pods falling to the ground are a messy problem in the urban setting. Honey locust, Gleditsia
triacanthos, is indigenous to the humid eastern North America in areas of hot
summers and cold winters. The pods
contain 29 percent sugar and are readily eaten by livestock. Honey locust is also a valuable ornamental
and timber tree. Many other tree legumes are of some importance in world
argriculture. There is another
mesquite, Prosopis glandulosa, a spiny shrub of the arid southwestern
deserts of North America. It has
pulpy pods that have long served as food for humans and livestock. The Rain Tree,
Samanea saman, a huge tropical American tree, bears curved black pods
that are filled with sweet pulp and which is an excellent livestock
feed. The Nittas,
Parkia biglobosa and P. filicoidea, of West Africa have large
pods with 31 percent sugar content.
The seeds yield a very nutritious flour with 36 percent protein, 23
percent fat, 15 percent starch and over 12 percent sugar. They are widely used by the natives when
traveling as they constitute a concentrated natural ration. In other parts of tropical America Inga
edulis and other species of the genus are cultivated for their pods,
which have a sweet and agreeable pulp, and as shade trees in coffee
plantations. The term “nut” is used loosely to
describe a number of related or unrelated plant structures. Officially a nut is a one-celled,
one-seeded dry fruit with a hard pericarp or shell. Some of the so-called nuts of commerce correspond to this
description. Among them are the
acorn, filbert, chestnut and hazelnut.
The others may be seeds, as the Brazil nut; legumes, such as the
peanut; or dry drupes from which the outer parts of the fruit have been
removed, such as the almond, coconut, pecan and walnut. The following discussion will group all of
these together regardless of their morphological nature. They will be classified according to their
fat, protein and carbohydrate contents.
The Brazil-nut tree, Bertholletia
excelsa, is a giant with a rough bark in the Amazon forests in South
America. It bears 18-24 hard, brown,
spherical, woody fruits from 4-6 inches in diameter and weighing 2-4
pounds. Each fruit contains 12-24 seeds
with a hard bony covering. These are
the Brazil nuts of commerce, also called Cream Nuts. They have served as human food for
centuries. The food value is very
high with a fat content of 65-70 percent and protein content of 17 percent. Collection and shipping of these nuts is
an important industry in South America.
Trees are rarely cultivated and most of the output is obtained from
the wild trees. There are also
similar nuts of finer quality and more delicate flavor obtained from the Sapucaia or Paradise-nut trees,
Lecythis usitata, Zabucajo sp., and other species. The cashew nut tree, Anacardium occidentale, is
a handsome native of Brazil that is now extensively cultivated in tropical countries
from Mexico to Peru and Brazil, in the West Indies, southern Florida and the
Mediterranean area, Mozambique, India, and the East Indies. It bears a thin-skinned, pear-shaped,
yellow or reddish, juicy “fruit” known as the Cashew
Apple. This is actually the
swollen peduncle and disk. The true
fruit, a small curved or kidney-shaped structure, is borne on the outside of
the “apple” at the distal end. This
is the cashew “nut.” The rich kernel is delicately flavored and contains
nutritious oil. The grayish-brown
coat, or shell, contains oil that blisters the skin. The ripe fruit, which as a characteristic
aroma, is consumed in many countries or used for preserves. The fermented juice makes a wine, Kaju
that is sometimes bottled. The
leaves, the light close-grained wood, the sap and the bark are also useful. This is one of the most important economic plants
especially in the South Pacific and other tropical areas. Coconut is a palm, Cocos nucifera,
probably native to the Malay archipelago, but possibly of Ecuadorian and
Central American origin. It grows
best near the seashore, but can occur at altitudes of 5,000 ft. It is undoubtedly one of the most graceful
and beautiful of all palms, often with a typical leaning habit. The bases of the slender trunks are
swollen. The large pinnate leaves are
6-12 ft. long and 18 in. wide. They
are borne in a cluster at the top of the stem. The flowers are formed in a large compound spadix, enclosed by
a spathe. The fruit is a 3-sided dry
drupe. It consists of a smooth rind,
or exocarp; a reddish-brown fibrous mesocarp; and a hard stony endocarp, or
shell that encloses the seed. The
white meat and milk represent the endosperm of the seed; the embryo is
embedded in the hard endosperm. The coconut plants have many uses. The leaves are highly incendiary that when
burned produce a bed of coals which imparts a delicious flavor to grilled
meats. The fibrous husk yields Coir, a textile fiber. The hard shell, or endocarp, is used for
fuel, vessels and other containers, and a fine grade of charcoal. The water of the green coconut makes an
agreeable and refreshing drink. The
meat may be eaten raw or shredded and dried to form desiccated coconut. It is frequently ground and pressed
through a cloth after water has been added.
The resulting coconut milk is very palatable and a good substitute for
cow’s milk as it contains several vitamins.
However, the main use of the meat is for copra, the source of coconut
oil and oil cake. The unopened
inflorescences yield a sweet liquid that is converted into palm sugar or
fermented to make palm wine, arrack, or vinegar. The leaves are also used for thatching, baskets, hats, mats and
curtains. The petioles and midribs
are used for fence posts, canes, brooms, needles and pins. The trunk furnishes a strong, durable wood
for houses and bridges. Some of the
porcupine wood of commerce, much used for cabinetwork, is from the
coconut. The heart of bud at the apex
of the stem is used in salads or is cooked.
The bark contains a resin and the roots a drug. Coconuts thrive best within the true tropics, but they
will grow at higher latitudes. They
grow best in fertile soils. Wild trees
are an important source of coconuts, but commercial plantations abound. Mature nuts are planted in a nursery and
barely covered. They germinate in a
few months and the seedlings are transplanted when about a year old. Proper spacing, clean cultivation and
intercropping improve growth. Cover
crops, fertilization and irrigation also help to maintain the yield. Flowering and fruiting at tropical
latitudes are continuous and ripe nuts can be obtained during every month of
the year. Harvest is usually every
two months. The yield and size of the
nuts vary with the spacing and the variety planted. About 3,000-7,000 nuts are required to produce one ton of
copra, which yields 1,200 lbs. of coconut oil and 800 lbs. of oil cake. One thousand nuts can yield 165 lbs. of
coir fiber. Great care must be taken
not to lie beneath the trees, as the fruit is very heavy and can cause grave
injury when falling. Driving them against a sharp spike fastened to a piece
of wood and wrenching them apart husk the coconuts. An experienced person can husk 1,200-2,500 nuts per day. The nuts are broken into two halves with a
blow of a heavy dull knife. The dried
meat or copra, the most important product, is prepared in different
ways. About half the supply is dried
by simple methods, using the sun or drying on racks over fires made from
coconut shells. After a few days the
meat curls away from the shell and can readily be detached. Copra prepared in this way is dark colored
and has an oil content of about 50 percent.
Plantation copra is dried within 24 hours in the sun followed by heat
from fires in drying houses. This
copra is white and has a high oil content (60-65 percent). The best grade of copra has traditionally
come from Sri Lanka. Desiccated coconut is used by confectionery and candy
makers and in cooking. It is prepared
from the best grade of nuts. These
are cured for several weeks and then carefully cracked and the meat is
removed while fresh. This is washed
and cut into threads and dried in a vacuum for one hour at 160 deg.
Fahrenheit. Hazelnuts, Corylus spp., are found in cool temperate
regions of both hemispheres. The
native American shrubs, Corylus americana and C. cornuta,
produce small nutritious and palatable nuts of no commercial importance. Larger European species, C. avellana
and C. maxima, are the source of Filberts,
Cob Nuts and Barcelona
Nuts. Filberts are cultivated
in Southern Europe and Oregon. Hickories, Carya spp., are native American trees
common throughout the eastern deciduous forest. Butternut hickories contain a large amount of tannin and are
not suitable for food but are eaten by livestock. Another group has sweetish edible nuts, the best of these being
the Shagbark Hickory, Carya ovata
and Shellbark Hickory, Carya laciniosa. These can be some of the finest of the
wild nuts in North America and they have excellent storage qualities. The trees show promise under selection and
experimentation. They can be grafted
and crossed and many new varieties adapted to a wide range of soil and
climatic conditions have been produced.
The nuts yield a fine salad oil and the wood is a valuable timber. The bark, which frequently sloughs off, is
used in smoking meats. Macadamia trees, Macadamia ternifolia, are
native to northeastern Australia.
They produce a nut also known as Queensland
Nuts. The tree has been
introduced into other subtropical areas of both hemispheres. It has become of considerable commercial
importance in Hawaii. Both
thin-shelled and thick-shelled varieties are grown. The kernels have a sweet flavor that is enhanced by roasting
and a rich oil. The Pecan Tree, Carya illinoensis, is indigenous
to the southeastern United States and northeastern Mexico. It is in the same genus as Hickory. The trees are extensively cultivated in
both the Southern states and points west all the way to California, in the
latter under irrigation. New
varieties have extended the production northward into the upper Mississippi
valley, Indiana and Virginia.
Harvesting begins when trees are only 3-4 years of age. Paper-shelled varieties have been
developed from East Texas stock.
Pecans have a high fat content of 70% and they are used in desserts,
candy, ice cream, cakes, etc. Pralines, consisting of brown sugar, vinegar and
nuts, are a favorite confection in the South. Pecan pie is a delicious blend of nuts with a brown sugar
custard base. Pecan oil and tannin
obtained from the shells are by-products.
The seeds of Canarium ovatum, a native tree of
the Philippines are Pili Nuts. They
are very similar to Java almonds from C. commune of Eastern Asia and
the East Indies. The seeds of both
are consumed raw or after roasting.
They have a spindle shape with a very thick hard shell. Fatty oil is expressed from the seed and
used for human consumption and in oil lamps, and a resin is extracted from
the tree. The plum-like fruit of the
Pili is also edible. Pine nuts or Piñons are
obtained from the seeds of several species of Pinus, native to Western
North America. Included are the Nut Pines, P. cembroides var. edulis and P.
edulis var. monophylla; the Digger Pine, P.
sabiniana; and the Torrey Pine, P.
torreyana. These bean-sized nuts
have a thin brownish-red shell and a slightly resinous flavor. Amerindians have always harvested
piñons. The pinecones are harvested
before they would open naturally.
They are then roasted so that the scales will fall apart, which allows
the seeds to separate. Wild birds and
rodents quickly gather them when they open naturally in nature. The production is entirely from wild
trees. Pignolia Nuts are the
seed of Pinus pinea of Southern Europe. These are longer and more yellow than piñons and have a rich
delicious taste. Other species of
pine provide edible nuts in India and Eastern Asia. China has increased its export of such nuts in the latter 20th
Century. Walnut trees provide both nuts and timber. They are native trees of North America and
Europe. Black Walnut, Juglans
nigra, is an abundant tree of the eastern deciduous forest region of
North America. It is a tall handsome
tree that is often used for ornamental purposes. The large spherical fruits are green when ripe and the outer
covering has to disintegrate or be physically removed to free the nuts. The walnut kernels have high oil content
and were a favorite food of Amerindians.
They retain their flavor when cooked and have a food value four times
as great as meat. They are very
difficult to crack and the husk stains the hands a dark brown so their wild
harvest today is restricted to the very dedicated. These nuts are used mainly in the candy and ice cream
industries. The tree is very
productive and can be grown in a variety of soils and climates. Walnuts provide a valuable timber and also
a brownish-black dye that was used by early settlers to dye hair.
Butternut,
Juglans cinerea, is native to area with limestone soil in eastern
North America. The tree is smaller
than Black Walnut with elliptical nuts that have a deeply corrugated
shell. Butternuts are high in fat
content and are often preferred to walnuts because of their finer and richer
flavor. The kernels are more readily
separated. Sugar is sometimes
obtained from the sap. They have
often been used in the candy industry. English Walnut, Juglans regia, [<Photos>] is indigenous to Iran and is widely cultivated in
Southern Europe, China and other parts of Asia. In North America California and Oregon are leading
producers. English walnut has been
under cultivation for ages and many varieties exist. The attractive trees are usually planted
in rows. Only the outer limbs produce
perfect nuts. The kernels are easily
freed from the pericarps and are bleached and polished. The furrowed kernels are the cotyledons of
the seed, no endosperm being present.
Walnuts yield excellent oil and the oil cake is a good livestock
feed. The codling moth, Carpocapsa
pomonella and Navel Orangeworm, Amyelois transitella, often attack the crop
in North America and biological agents (parasitic insects) have been
partially successful in control.
Nuts with High Protein Content Almonds are probably the most popular of the high
protein nuts. They are obtained from
a medium-sized tree, Prunus amygdalus that is related to the peach and
closely resembles it in blossoms and young fruit. Almond trees are also cultivated as ornamentals. The almond fruit is an edible drupe, with a
tough fibrous rind surrounding the stone or “shell” and the seed or
“nut.” There are two major types of
almonds. Sweet Almonds, Prunus
amygdalus var. dulcis, have an edible seed and are the main source of the
commercial product. The tree is
native to the eastern Mediterranean where it has been cultivated for
centuries. It is grown throughout
Southern Europe and in California, Australia and South Africa. The seeds are especially delicious when
eaten green. However, they are
usually roasted or salted or made into a paste to be used for cake and
bread. An extract is also prepared
for flavoring. There are many
varieties, some with think shells and some with hard shells. Jordan almonds are hard-shelled with a
thinner integument on the seed and a finer flavor. In California a successful biological control effort against the
Navel Orangeworm, Amyelois transitella, reduced harvest losses to
below four percent. Bitter Almonds, Prunus
amygdalus var. amara, possess a bitter glucoside, Amygdalin
that readily breaks down into prussic acid and thus prevents their use as
food. Nevertheless, they are grown in
Southern Europe as a source of the oil.
During the extraction process the prussic acid is eliminated and the
oil can then be used for flavoring.
Bitter almonds are also used as a rootstock for sweet almonds. The beech tree, Fagus grandifolia, is abundant
in the eastern deciduous forest of North America. The high protein nuts are small, triangular and very
sweet. They are of minor importance for
human food, but are eagerly sought after by cattle, pigs, squirrels, poultry
and other birds. They impart a fine
flavor to pork, and razorback hogs are fed on the mast, which is a mixture of
beechnuts, chestnuts and acorns. The
European beech, Fagus sylvatica, yields slightly larger nuts that are
consumed by humans and used for the edible oil of beechnuts. Pistachio, Pistacia vera, also known as Green Almond, is a small tree indigenous to
Western Asia. It has been cultivated
in the Mediterranean region since before 2,000 B.C. It is now grown in Iran, Afghanistan, the southern United
States and irrigated areas of the West, especially California. The fruit is a drupe. The seed contain two large green
cotyledons with a reddish covering.
These high protein “nuts” are salted in brine while still in the
shell. They are highly prized for
their color and resinous flavor and are combined with other nuts as mixed
nuts and as a flavoring material for ice cream and candy. Their quality varies with the kind of
culture. Restricting water reduces
yield be improves flavor. Nuts with High Carbohydrate Content Acorns are the fruits of oak trees, Quercus spp. They are true nuts. Acorns have been used in America for fattening
livestock, especially hogs. They are
an excellent human food, but are rarely used except by indigenous
people. The white oak, Quercus
alba, and the live oak, Q. virginiana, are the best of the twelve
or more species with edible fruit.
The Amerindians have always used acorn flour. They ground the nuts, leached them to
remove the tannin and other bitter qualities, pounded them into a meal and
used them in porridge, mush and other ways.
Acorns have been used in other areas of the world, for example they
once furnished 25 percent of the food of the poorer classes in Italy and
Spain in the form of acorn bread or cake.
This is highly nutritious and may be stored indefinitely. Any species of acorn is edible after the
tannin has been removed, but the holm oak, Q. ilex, is the main
source. Oak trees are very productive
and adapted to poor soil. The problem
with acceptance of this food is its unaccustomed flavor, which is probably
related to few persons being able to prepare it properly. <bot120> Southern Live Oak, Quercus virginiana.,
South Texas <bot243> Jeffrey Pine (Pinus jeffreyi )
& California Black Oak (Quercus kelloggii), San Bernardino Mts.,
California <bot301>
Canyon Live Oak (Quercus chrysolepis), Palomar Mts., California <bot375> California Black Oak (Quercus kelloggii),
San Bernardino Mts., California Chestnuts, Castanea spp., are found in the
eastern United States, Japan and Europe.
The American species, Castanea dentata, was once very abundant
in the deciduous forest region. It
was a handsome tree and furnished valuable timber as well as excellent
quality nuts. These served as food,
either raw or roasted, for over 200 years.
Chestnut blight disease has about eradicated this tree from America,
with no fruiting observed since the middle of the 20th Century. The European chestnut, C. sativa, with
larger fruits has been extensively cultivated in Southern Europe for
centuries and hundreds of varieties have been established. The nuts or marrons as they are called,
are a standard food and are as important as wheat maize in America. They are grown everywhere, often on dry
hillsides that are unfit for other purposes.
The nuts are consumed raw or are roasted, boiled or used for stuffing
or flour. The Japanese chestnut, C.
crenata, is immune to chestnut blight and has been introduced into
America. The nuts are often cooked
like potatoes. <bot735>
American Chestnut (Bombacopsis glabra A. Robyns) (roasted seeds) [Neotropics] <bot841>
European Chestnut (Castanea sativa) (roasted fruit) [Europe] <Photos> Other Crops Where Seeds are Used <bot754> Black Apple (Diospyros digyna Jacq.) ( |