From the book
Fruits of Warm Climates
by Julia F. Morton
Date
Phoenix
dactylifera
PALMAE
Most of the dozen or more species of the genus Phoenix (family
Palmae) are grown as ornamental palms indoors or out. Only the common
date, P. dactylifera
L., is cultivated for its fruit. Often called the edible date, it has
few alternate names except in regional dialects. To the French, it is
dattier; in German, it is dattel; in Italian, datteri; or dattero; in
Spanish, datil; and, in Dutch, dadel. The Portuguese word is tamara.
Fig. 1: An 8-year old-'Deglet Noor' date palm in a private garden near
Indio, California. Photo'd by Avery Edwin Field, Oct. 1924. In: W.T.
Swingle, Date Growing: a new industry for Southwest States U.S. Dept.
of Agriculture Yearbook 1926.
Description
The date is an erect palm to 100 or 120 ft (30.5-36.5 m), the trunk
clothed from the ground up with upward-pointing, overlapping,
persistent, woody leaf bases. After the first 6 to 16 years, numerous
suckers will arise around its base. The feather-like leaves, up to 20
ft (6 m) long, are composed of a spiny petiole, a stout midrib, and
slender, gray-green or bluish-green pinnae 8 to 16 in (20-40 cm) long,
and folded in half lengthwise. Each leaf emerges from a sheath that
splits into a network of fibers remaining at the leaf base. Small
fragrant flowers (the female whitish, the male waxy and cream colored),
are borne on a branched spadix divided into 25 to 150 strands 12 to 30
in (30-75 cm) long on female plants, only 6 to 9 in (15-22.5 cm) long
on male plants. One large inflorescence may embrace 6,000 to 10,000
flowers. Some date palms have strands bearing both male and female
flowers; others may have perfect flowers. As the fruits develop, the
stalk holding the cluster may elongate 6 ft (1.8 m) while it bends over
because of the weight. The fruit is oblong, 1 to 3 in (2.5-7.5 cm)
long, dark-brown, reddish, or yellowish-brown when ripe with thin or
thickish skin, thick, sweet flesh (astringent until fully ripe) and a
single, cylindrical, slender, very hard stone grooved down one side.
Origin and Distribution
The date palm is believed to have originated in the lands around the
Persian Gulf and in ancient times was especially abundant between the
Nile and Euphrates rivers. Alphonse de Candolle claimed that it ranged
in prehistoric times from Senegal to the basin of the Indus River in
northern India, especially between latitudes 15 and 30. There is
archeological evidence of cultivation in eastern Arabia in 4,000 B.C.
It was much revered and regarded as a symbol of fertility, and depicted
in bas relief and on coins. Literature devoted to its history and
romance is voluminous. Nomads planted the date at oases in the deserts
and Arabs introduced it into Spain. It has long been grown on the
French Riviera, in southern Italy, Sicily and Greece, though the fruit
does not reach perfection in these areas. Possibly it fares better in
the Cape Verde Islands, for a program of date improvement was launched
there in the late 1950's. Iraq has always led the world in date
production. Presently, there are 22 million date palms in that country
producing nearly 600,000 tons of dates annually. The Basra area is
renowned for its cultivars of outstanding quality. The date has been
traditionally a staple food in Algeria, Morocco, Tunisia, Egypt, the
Sudan, Arabia and Iran. Blatter quotes the writer, Vogel, as stating:
"When Abdel-Gelil besieged Suckna in 1824, he cut down no fewer than
43,000 trees, to compel the town to surrender; nevertheless, there are
still at least 70,000 left."
In 1980, production in Saudi Arabia was brought to nearly a
half-million tons from 11 million palms because of government
subsidies, improved technology, and a royal decree that dates be
included in meals in government and civic institutions and that
hygienically-packed dates be regularly available in the markets.
Farmers receive financial rewards for each offshoot of a high-quality
date planted at a prescribed spacing. The Ministry of Agriculture has
established training courses throughout the country to teach modern
agricultural methods, including mechanization of all possible
operations in date culture, and recognition and special roles of the
many local cultivars. In West Africa, near the Sahara, only dry, sugary
types can be grown.
Bonavia introduced seeds of 26 kinds of dates from the Near East into
northern India and Pakistan in 1869; and, in 1909, D. Milne, the
Economic Botanist for the Punjab, introduced offshoots and established
the date as a cultivated crop in Pakistan. The fruits ripen well in
northwestern India and at the Fruit Research Center in Saharanpur. In
southern India, the climate is unfavorable for date production. A few
trees around Bohol in the Philippines are said to bear an abundance of
fruits of good quality. The date palm has been introduced into
Australia, and into northeastern Argentina and Brazil where it may
prosper in dry zones. Some dates are supplying fruits for the market on
the small island of Margarita off the coast from northern Venezuela.
Seed-propagated dates are found in many tropical and sub-tropical
regions where they are valued as ornamentals but where the climate is
unsuitable for fruit production.
In November 1899, 75 plants were sent from Algiers to Jamaica. They
were kept in a nursery until February 1901 and then 69 were planted at
Hope Gardens. The female palms ultimately bore large bunches of fruits
but they were ready to mature in October during the rainy season and,
accordingly, the fruits rotted and fell. Only occasionally have date
palms borne normal fruits in the Bahamas and South Florida.
Spanish explorers introduced the date into Mexico, around Sonora and
Sinaloa, and Baja California. The palms were only seedlings. Still, the
fruits had great appeal and were being exported from Baja California in
1837. The first date palms in California were seedlings planted by
Franciscan and Jesuit missionaries in 1769. Potted offshoots from Egypt
reached California in 1890 and numerous other introductions have been
made into that state and into the drier parts of southern Arizona
around Tempe and Phoenix. In 1912, Paul and Wilson Popenoe purchased a
total of 16,000 offshoots of selected cultivars in Algeria, eastern
Arabia and Iraq and transported them to California for distribution by
their father, F.O. Popenoe who was a leader in encouraging date culture
in California. It became a profitable crop, especially in the Coachella
Valley. There are now about a quarter of a million bearing trees in
California and Arizona.
Varieties
It would be impractical to deal in depth with date cultivars here. Paul
Popenoe listed 1,500 and provided descriptions of the fruit and palm,
as well as the history and significance, of the most important, country
by country, in 90 pages of his book, The Date Palm, written in 1924 but
published in 1973 and readily available. In Iraq, there are presently
450 female cultivars, the most important of which are: 'Zahdi' (43% of
the crop; low in price); 'Sayer' 23% of the crop and high-priced);
'Halawi' (13% of the crop and high-priced); 'Khadrawi (6% of the crop
and high-priced); also 'Khastawi, 'Brem', and 'Chipchap'. Sawaya and
colleagues (1983) have reported on the sugars, tannins and vitamins in
55 major date cultivars of Saudi Arabia.
The following, with brief comments, are the dates most commonly grown:
'Barhi'—
introduced into California in 1913 from Basra, Iraq;
nearly cylindrical, light amber to dark brown when ripe; soft, with
thick flesh and rich flavor; of superb quality. For shipment needs
refrigeration as soon as picked, then curing and special packing.
'Dayri' (the
"Monastery Date")—introduced into California
from convent grounds in Dayri, Iraq, in 1913; long, slender, nearly
black, soft. Palm requires special care. Not grown extensively in
California.
'Deglet Noor'
'Halawi'
'Zahdi' |
Fig. 2: 'Deglet Noor', (top) a semi soft date. 'Halawi', (center) a
leading export date of Iraq. 'Zahdi', (bottom) a small date from
northern Iraq. In: D.W. Albert and R H. Hilgeman, Date growing in
Arizona. Bull. 149, U. Arizona, Agr. Exper. Sta., Tucson, Ariz. May
1935.
'Deglet Noor'—a
leading date in Algeria and Tunisia; and in
the latter country it is grown in inland oases and is the chief export
cultivar. It was introduced into California in 1900 and now constitutes
75% of the California crop. It is semi-dry, not very sweet; keeps well;
is hydrated before shipping. Much used for cooking. The palm is high
yielding but not very tolerant of rain and atmospheric humidity.
'Halawy'
('Halawi')—introduced into California from Iraq;
soft, extremely sweet, small to medium; may shrivel during ripening
unless the palm is well-watered. It is especially tolerant of humidity.
'Hayany'
('Hayani')—the cultivar most extensively planted in
Egypt; but not exported. Introduced into California in 1901, and is
sold fresh; is not easy to cure. The fruit is dark-red to nearly black;
soft. The palm is one of the most cold-tolerant.
'Khadrawy'
('Khadrawi')—important in Iraq and Saudi Arabia,
and is grown to some extent in California and Arizona. It is the
cultivar most favored by Arabs but too dark in color to be popular on
the American market, though it is a soft date of the highest quality.
It is early-ripening; does not keep too well. This cultivar is the
smallest edible date palm grown in the United States and it is fairly
tolerant of rain and humidity.
'Khastawi'
('Khustawi'; 'Kustawy')—the leading soft date in
Iraq; sirupy, small in size; prized for dessert; keeps well. The palm
is large and vigorous and produces its offshoots high on the trunk in
California. The fruit is resistant to humidity.
'Maktoom'—introduced
into California from Iraq in 1902;
large, red-brown; thick-skinned, soft, mealy, medium sweet; resistant
to humidity.
'Medjool'—formerly
exported from Morocco; 11 off-shoots
imported into California from Bou Denib oases in French Morocco in
1927; is now marketed as a deluxe date in California; is large, soft,
and luscious but ships well.
'Saidy'
('Saidi')—highly prized in Libya; soft, very sweet;
palm is a heavy bearer; needs a very hot climate.
'Sayer'
('Sayir')—the most widely grown cultivar in the Old
World and much exported to Europe and the Orient; dark orange-brown, of
medium size, soft, sirupy, and sometimes some of the sirup is drained
out and sold separately; not of high quality but the palm is one of the
most tolerant of salt and other adverse factors.
'Thoory'('Thuri')—popular
in Algeria; does well in
California. Fruit is dry; when cured is brown-red with bluish bloom
with very wrinkled skin and the flesh is sometimes hard and brittle but
the flavor is good, sweet and nutty. Keeps well; often carried on
journeys. The palm is stout with short, stiff leaves; bears heavily,
and clusters are very large; somewhat tolerant of humidity.
'Zahdi'
('Zahidi')—the oldest-known cultivar, consumed in
great quantity in the Middle East; introduced into California about
1900. Of medium size, cylindrical, light golden-brown; semi-dry but
harvested and sold in 3 stages: soft, medium-hard, and hard: very
sugary; keeps well for months; much used for culinary purposes. The
palm is stout, fast growing, heavy bearing; drought resistant; has
little tolerance of high humidity.
Among the less well-known cultivars in California are:
'Amir Hajj'—introduced
from Mandali Oasis in Iraq in 1929.
The fruit is soft, with thin skin and thick flesh; of superior quality
but little grown in the United States.
'Iteema'—offshoots
from Algeria were introduced into
California in 1900. The fruit is large, oblong, light amber, soft, very
sweet. Much grown in Algeria but not rain resistant and little grown in
California.
'Migraf'
('Mejraf)—a very popular cultivar in Southern Yemen.
Fruit is light golden-amber, large; of good quality.
In inland oases of Tunisia, in addition to the 'Deglet Noor', there is
'Ftimi' ('Alligue') which is equally subject to humidity, less
productive and less disease-resistant.
'Manakbir'
has a large fruit and ripens earlier but has the
disadvantage that the palm produces few offshoots and its
multiplication is limited.
In coastal oases, the main cultivars are 'Kenta', Agnioua', 'Bouhatam'
and 'Lemsi' which come into season early and ripen before the fall
rains. They require less heat than other cultivars. The fruits are more
or less dry and the flesh firm.
In all date-growing areas, some confusion is caused if a seed from
harvested fruits falls at the base of a select cultivar and the
seedling springs up unnoticed among the offshoots. Such seedlings
should be watched for and discarded lest they be mistakenly
transplanted with the offshoots and later bear fruits of inferior
quality.
Pollination
Date pollen is abundant but is not airborne very far. It has become
customary to plant one male palm for every 48 or 50 females to provide
pollen for artificial pollination which is an ancient practice. In
Saudi Arabia and a few other areas of the Old World and in California
and Arizona, the long spines on the petioles are first removed to
facilitate the pollinating operation. Traditionally, a few strands of
open male flowers are put upside-down in a female inflorescence while
it is still upright, and a cord is bound around the latter to keep the
strands in place when the cluster enlarges and bends downward. However,
the pollen can be dried and will keep for 6 months at room temperature.
Pollen stored for one year at 8°F (-13.33°C) has given
58% fruit set. Some has been found viable
after 7 years of storage, and it is reported that pollen has been kept
14 years in Iran. There are various techniques for applying stored
pollen to the female flowers. It may be dusted on by a tractor-drawn,
convertible pollen/pesticide machine, or applied with a cotton pad, or
sprayed on with a long tubed applicator or other device. Lack of
pollination results in small, seedless fruits. In acute shortages,
pollen of another species of Phoenix or of some other genera may be
used.
Climate
The date palm must have full sun. It cannot live in the shade. It will
grow in all warm climates where the temperature rarely falls to
20°F (-6.67°C). When the palm is dormant, it can stand
temperatures that low, but when in flower or fruit the mean temperature
must be above 64°F (17.78°C). Commercial fruit
production is possible only where there is a long, hot growing season
with daily maximum temperatures of 90°F (32.22°C) and
virtually no rain less than 1/2 in (1.25 cm) in the ripening season. The
date can tolerate long periods of drought though, for heavy bearing, it
has a high water requirement. This is best supplied by periodic
flooding from the rivers in North Africa and by subsurface water rather
than by rain. (See remarks on irrigation under "Culture").
Soil
The date thrives in sand, sandy loam, clay and other heavy soils. It
needs good drainage and aeration. It is remarkably tolerant of alkali.
A moderate degree of salinity is not harmful but excessive salt will
stunt growth and lower the quality of the fruit.
Propagation
Date palms grow readily from seeds if the seeds and seedlings are kept
constantly wet. But seedlings are variable and take 6 to 10 years to
fruit. Furthermore, 50% of the seedlings may turn out to be males. The
best and common means of propagation is by transplanting the suckers,
or offshoots when they are 3 to 5 years old and weigh 40 to 75 lbs
(18-34 kg). They are usually separated from the parent palm as needed,
but in southern Algeria suckers are often put on sale standing in tubs
of water. Some offshoots are maintained in nurseries until roots are
formed, though most are set directly in the field after a seasoning
period of 10 to 15 days just lying on the ground, in order to lose 12
to 15% of their moisture. In parts of Egypt subject to annual flooding,
very large offshoots up to 500lbs (226 kg) are planted to avoid water
damage. In general, it is said that at least 2 offshoots can be taken
from each palm annually for a period of 10 to 15 years. The potential
of tissue culture for multiplication of date palms is being explored in
Iraq, Saudi Arabia and in California.
Culture
In Tunisia, in former times, it was customary to plant 200 date palms
per acre (500/ha). Today, optimum density is considered to be 50 per
acre (120/ha) and this is about the standard in the Coachella Valley of
California, but small-growing palms may be set much closer. The off
shoots, trimmed back 1/3 or 1/4, leaving some of the stiff outer leaves
to protect the inner ones, are usually planted 30 to 33 ft (9-10 m)
apart each way. The holes should be 3 ft (0.9 m) wide and deep,
prepared and enriched several months in advance, and may be encircled
by a watering ditch. If the soil dries out prior to planting, the holes
are filled with water at that time. In Algeria and Oman, the palms may
be set much deeper in order to be closer to ground water, but this may
result in drowning the palms when irrigating or they may be smothered
by sandstorms.
Planting may be done at any time of year, but most often takes place in
spring or fall. In Tunisia planting is done in April and May. The base
is set vertically in the ground and the curving fronds will gradually
assume an upright position, especially if the concave side is set to
face south. Most plants will root in 2 months if the soil is kept
constantly moist, while some may be delayed for a year or even several
years before they show vigorous growth. Some growers expect a loss of
25% of the off shoots. Formerly, the young plants in nursery rows were
wrapped nearly to the top with old leaves, paper or burlap sacks for
the first year to prevent dehydration by cold, heat or wind. But it is
now held that such wrapping interferes with the proper development of
the leaves.
The offshoots that survive may begin to bloom in 3 years and fruit a
year later but a substantial crop is not possible before the 5th or 6th
year. In 8 or 10 years, the date will attain full production and it
will keep on for a century though productivity declines after 60 to 80
years and also the flowers will be too high to pollinate and the fruits
too high to pick. The palm grows at the rate of 1 to 11/2 ft (30-45 cm)
a year and can reach 20 ft in 15 to 20 years depending on the cultivar
and soil and water conditions.
In Iraq, date palms are fertilized once a year with manure at the rate
of 44 lbs (20 kg) per tree. Commercial fertilizers are utilized in
Saudi Arabia and the United States. Of more importance is the supply of
water, a large amount being necessary and it is usually supplied by
irrigation ditches. In some Old World plantations rising tides cause
rivers to flood the ditches twice a day. Where this natural irrigation
does not occur, the palms are watered 15 to 40 times a year. Overhead
moisture (including rain) during fruit development will cause minute
cracks (checking), beginning at the apex of the fruit which ultimately
darkens. In California, the fruit clusters are covered with paper bags
to shelter them from rain, dust, and predators.
The female inflorescences may be shortened, thinned out, or some
removed entirely at pollinating time, or several weeks later when the
stalk has drooped lower, in order to conserve the palm's energy for the
following season. Some growers advise leaving no more than 12 bunches
per palm. Many leave only 30 strands per cluster, each with about 30
fruits. Without thinning, fruits would be borne only every other year.
During the pollinating operation, a grower may tie the elongating
flower stalk to a palm frond to prevent breaking when later laden with
fruit.
The palms are pruned twice a year, dry fronds being removed in the fall
and the leaf bases may be taken off in the spring in order that their
fiber may be used as a substitute for coir.
In Iraq, growth regulators have been experimentally applied to
developing dates. In 'Zahdi' and 'Sayer', naphthaleneacetic acid, at 60
ppm, applied 15 to 16 weeks after pollination, improved quality and
increased fruit weight by 39%. Moisture content was elevated. Ripening
was delayed for 30 days or more.
In the Old World, most date plantations are intercropped with
vegetables, cereals or fodder crops in the first few years and
subsequently with low growing fruit trees or grapevines. Some
authorities hold that this practice distracts the grower from proper
care of the dates. In mechanized plantations, intercropping is not
possible inasmuch as space must be left for the mobile equipment.
Yield
Ordinarily, in palms 5 to 8 years old, the first crop will be 17.5 to
22 lbs (8-10 kg) per palm; at 13 years, 132 to 176 lbs (60-80 kg). Some
improved cultivars, at high densities, have yielded over 220 lbs (100
kg) per year. 'Deglet Noor' in California may yield 4.5 to 7 tons per
acre (11-17 tons/ha).
Harvesting and Ripening
Some high-quality dates are picked individually by hand, but most are
harvested by cutting off the entire cluster. In North Africa, the
harvesters climb the palms, use forked sticks or ropes to lower the
fruit clusters, or they may pass the clusters carefully down from hand
to hand. Growers in California and Saudi Arabia use various mechanized
means to expedite harvesting saddles, extension ladders, or mobile
steel towers with catwalks for pickers. All fruits in a cluster and all
clusters on a palm do not ripen at the same time. A number of pickings
may have to be made over a period of several weeks. In the Coachella
Valley, dates ripen from late September through December and there are
6 to 8 pickings per palm.
Dates go through 4 stages of development: 1) Chimri, or Kimri, stage,
the first 17 weeks after pollination: green, hard, bitter, 80%
moisture, 50% sugars (glucose and fructose) by dry weight; 2) Khalal
stage, the next 6 weeks: become full grown, still hard; color changes
to yellow, orange or red, sugars increase, become largely sucrose; 3 )
Rutab stage, the next 4 weeks: half-ripe; soften, turn light brown;
some sucrose reverts to reducing sugar which gains prominence; 4) Tamar
stage: ripe; the last 2 weeks; in soft dates, the sugar becomes mostly
reducing sugar; semi-dry and dry dates will have nearly 50% each of
sucrose and reducing sugars.
Soft dates may be picked early while they are still light colored. Semi
dry dates may be picked as soon as they are soft and then ripened
artificially at temperatures of 80° to 95°F
(26.67°-35°C), depending on the cultivar. Dry dates may
be left on the palm until they are fully ripe. Dry dates that have
become too dehydrated and hardened on the palm are rehydrated by
soaking in cold, tepid or hot water, or by exposure to steam or a humid
atmosphere. Extremely dry weather will cause dates to shrivel on the
palm. In the Sudan, the fruits are picked when just mature and then are
ripened in jars to prevent so much loss of moisture. Rain, high
humidity or cool temperatures during the maturing period may cause
fruit drop or checking, splitting of the skin, darkening, blacknose,
imperfect maturation, and excessive moisture content, or even rotting.
Under such adverse weather conditions, as may occur in the Salt River
Valley, Arizona, dates must be harvested while still immature and
ripened artificially. In the Old World, there are many different
methods of doing this: storing in earthen jars, placing the jars in sun
hot enough to prevent spoilage, boiling the fruits in water and then
sun drying. In Australia, entire clusters are kept under cover with the
cut end of the stalk in water until the fruits are fully ripe. In
modern packing houses, prematurely harvested dates are ripened in
controlled atmospheres, the degrees of temperature and humidity varying
with the nature of the cultivar.
Where there is low atmospheric humidity outdoors and adequate sunshine,
harvested dates are sun dried whole or cut in half. For fresh shipment
in California, the normally ripe, harvested fruits are carried to
packing plants, weighed, inspected by agents of the United States
Department of Agriculture, fumigated, cleaned, graded, packed, stored
under refrigeration, and released to markets according to demand. Saudi
Arabia has constructed a number of extra-modern processing plants for
fumigation, washing, drying, and packing of dates prior to cold storage.
Keeping Quality
Slightly underripe 'Deglet Noor' dates will keep at 32°F
(0°C) up to 10 months; fully mature, for 5 to 6 months.
Freezing will extend the storage life for a much longer period. In
India, sun-dried dates, buried in sand, have kept well for 1 1/2 years
and then have been devoured by worms.
Pests and Diseases
Unripe fruits are attacked by Coccotrypes
daclyliperda which makes them fall prematurely. Ripe
fruits are often infested by nitidulids—Carpophilus hemipterus, C. multilatus (C. dimidiatus), Urophorus humeralis,
and Heptoncus luteolus,
which cause decay. Control by insecticides is necessary to avoid
serious losses. In Israel, the fruit clusters are covered with netting
to protect them from such pests as Vespa
orientalis, Cadra figulilella and Arenipes sabella as
well as from depredations by lizards and birds.
In Pakistan, the red weevil, or Indian palm weevil, Rhynchophorus ferrugineus,
bores into the leaf bases at the top of the trunk, causing the entire
crown to wither and die. The rhinocereus beetle, or black palm beetle, Oryctes rhinocerus,
occasionally attacks the date. Its feeding damage may provide
entrance-ways for the weevil. Scale insects may infest the leaves and
the trunk. They have been controlled by trimming off the heavily
infested leaves, spraying the remaining ones, and treating the fire
resistant trunk with a blowtorch. Two of the most destructive scales
are the Marlatt scale, Phoenicoccus
marlatti; which attacks the thick leaf bases, and the
Parlatoria scale, Parlatoria
blanchardii, which is active in summer. The latter was the
object of an eradication campaign in California and Arizona in the late
1930's. The date mite scars the fruits while they are still green.
A tineid moth and a beetle, Lasioderma
testacea, have damaged stored dates in the Punjab. Dates
held in storage are subject to invasion by the fig-moth, Ephestia
cautella, and the Indian meal-moth, Plodia interpunctella.
Fusarium
albedinis causes the disastrous Bayoud, or Baioudh,
disease in Morocco and Algeria. It is evidenced by a progressive fading
and wilting of the leaves. Over a 9-year study period of 26 resistant
varieties in Morocco, Bayoud disease reduced the planting density from
364 palms per acre (900/ha) to 121 to 142 per acre (300-350/ha). It is
because of this disease that 'Medjool' can no longer be grown
commercially in Morocco and Algeria.
Decay of the inflorescence is caused by Manginiella scaeltae
in humid seasons. Several brown stains will be seen on the unopened
spathe and the pedicels of the opened cluster will be coated with white
"down". Palm leaf pustule, small, dark-brown or black cylindrical
eruptions exoding yellow spores, resulting from infestation by the
fungus Graphiola
phoenicis, is widespread but often a serious problem in
Egypt. Date palm decline may be physiological or the result of a
species of the fungus genus Omphalia. Diplodia disease is a fungus
manifestation on leafstalks and offshoots and it may kill the latter if
not controlled. The fungus caused condition called "black scorch"
stunts, distorts and blackens leaves and adjacent inflorescences. Other
fungus diseases include pinhead spot (Diderma effusum),
gray blight (Pestalotia
palmarum) and spongy white rot (Polyporus adustus).
The date, as well as its relative, Phoenix
canariensis Hort. ex Chaub., has shown susceptibility to
lethal yellowing in Florida and Texas. No commercial plantings have
been affected.
Food Uses
Dry or soft dates are eaten out-of-hand, or may be seeded and stuffed,
or chopped and used in a great variety of ways: on cereal, in pudding,
bread, cakes, cookies, ice cream, or candy bars. The pitting may be
done in factories either by crushing and sieving the fruits or, with
more sophistication, by piercing the seed out, leaving the fruit whole.
The calyces may be mechanically removed also. Surplus dates are made
into cubes, paste, spread, powder (date sugar), jam, jelly, juice,
sirup, vinegar or alcohol. Discolored and filtered date juice yields a
clear invert sugar solution. Libya is the leading producer of date
sirup and alcohol.
Cull fruits are dehydrated, ground and mixed with grain to form a very
nutritious stockfeed. Dried dates are fed to camels, horses and dogs in
the Sahara desert. In northern Nigeria, dates and peppers added to the
native beer are believed to make it less intoxicating. The First
International Date Conference was held in Tripoli, Libya in 1959, and
led to the development of a special program under the Food and
Agriculture Organization of the United Nations to promote the
commercial utilization of substandard or physically defective dates.
Young leaves are cooked and eaten as a vegetable, as is the terminal
bud or heart, though its removal kills the palm. In India, date seeds
are roasted, ground, and used to adulterate coffee. The finely ground
seeds are mixed with flour to make bread in times of scarcity.
In North Africa, Ghana and the Ivory Coast, date palms are tapped for
the sweet sap which is converted into palm sugar, molasses or alcoholic
beverages, but each palm should not be tapped more than 2 or 3 times.
Tapping the edible date palm interferes with fruit production and it is
wiser to tap P.
sylvestris, which is not valued for its fruit, or some
other of the 20 well-known palm species exploited for sugar. When the
terminal bud is cut out for eating, the cavity fills with a thick,
sweet fluid (called lagbi in India) that is drunk for refreshment but
is slightly purgative. It ferments in a few hours and is highly
intoxicating. Fresh spathes, by distillation, yield an aromatic fluid
enjoyed by the Arabian people.
| Food
Value Per
100 g of Edible Portion* |
|
Fresh, uncooked |
Dried |
| Calories |
142 |
274 293 |
| Moisture |
31.9 78.5 g |
7.0 26.1 |
| Protein |
0.9 2.6 g |
1.7 3.9 g |
| Fat |
0.6 1.5 g |
0.1 1.2 g |
| Carbohydrates |
36.6 g |
72.9 77.6 g |
| Fiber |
2.6 4.5 g |
2.0 8.5 g |
| Ash |
0.5 2.8 g |
0.5 2.7 g |
| Calcium |
34 mg |
59 103 mg |
| Phosphorus |
350 mg |
63 105 mg |
| Iron |
6.0 mg |
3.0 13.7 mg |
| Potassium |
? |
648 mg |
Vitamin A
(ß carotene)
|
110-175
mcg |
15.60 mg |
| Thiamine |
? |
0.03 0.09 mg |
| Riboflavin |
? |
0.10 0.16 mg |
| Niacin |
4.4-6.9 mg |
1.4 2.2 mg |
| Tryptophan |
? |
10 17 mg |
| Ascorbic Acid |
30 mg |
0 |
*Based on standard analyses. |
|
Sawaya et al., in their studies of fresh dates in Saudi Arabia,
reported ascorbic acid content as 1.8-14.3 mg/100 g in the Khalal
stage; 1.1-6.1 in the Tamar state. They found that vitamin A ranged
from 20 to 1.416 I.U. in the Khalal stage; from 0-259 l.U. in the Tamar
stage. Tannin varied from 1.2 to 6.7% in the Khalal stage. 0.6 to 3.2 %
in the Tamar stage.
The sap contains 10% sucrose. Jaggery made from it contains 9.6%
moisture, 86.1 % carbohydrates, 1.5% protein, 0.3% fat, 2.6% minerals,
0.36% calcium, 0.06% phosphorus.
Other Uses
Seeds:
Date seeds have been soaked in water until soft and then fed to
horses, cattle, camels, sheep and goats. Dried and ground up, they are
now included in chicken feed. They contain 7.17-9% moisture, 1.82-5.2%
protein. 6.8-9.32% fat, 65.5% carbohydrates, 6.4-13 6% fiber,
0.89-1.57% ash, also sterols and estrone, and an alkali-soluble
polysaccharide. The seeds contain 6 to 8% of a yellow-green, non-drying
oil suitable for use in soap and cosmetic products. The fatty acids of
the oil are: lauric, 8%; myristic, 4%; palmitic, 25%; stearic, 10%,
oleic, 45%, linoleic, 10%; plus some caprylic and capric acid. Date
seeds may also be processed chemically as a source of oxalic acid, the
yield amounting to 65%. In addition, the seeds are burned to make
charcoal for silversmiths, and they are often strung in necklaces.
Leaves:
In Italy, there are some groves of date palms maintained solely
to supply the young leaves for religious use on Palm Sunday. In Spain,
only the leaves of male palms are utilized for this purpose. In North
Africa, the leaves have been commonly used for making huts. Mature
leaves are made into mats, screens, baskets, crates and fans. The
processed leaflets, combined with ground up peanut shells and corn
cobs, are used for making insulating board. The leaf petioles have been
found to be a good source of cellulose pulp. Dried, they are used as
walking sticks, brooms, fishing floats, and fuel. The midribs are made
into baskets. The leaf sheaths have been prized for their scent. Fiber
from the old leaf sheaths is used for various purposes including
packsaddles, rope, coarse cloth and large hats. It has been tested as
material for filtering drainage pipes in Iraq, as a substitute for
imported filters. Analyses of the leaves show: 0.4-0.66% nitrogen;
0.025 0.062% phosphorus; 0.33-0.66% potassium; 10-16.4% ash. There is
some coumarin in the leaves and leaf sheaths.
Fruit clusters:
The stripped fruit clusters are used as brooms. The
fruit stalks contain 0.28-0.42% nitrogen, 0.017-0.04% phosphorus;
3.46-4.94% potassium; 7.7-9.88% ash.
Fruits:
In Pakistan, a viscous, thick sirup made from the ripe fruits,
is employed as a coating for leather bags and pipes to prevent leaking.
Wood:
Posts and rafters for huts are fashioned of the wood from the
trunk of the date palm, though this wood is lighter than that of the
coconut. It is soft in the center and not very durable. That of male
trees and old, un productive females is readily available and used for
aqueducts, bridges and various kinds of construction, also parts of
dhows. All left over parts of the trunk are burned for fuel.
Medicinal Uses:
The fruit, because of its tannin content, is used
medicinally as a detersive and astringent in intestinal troubles. In
the form of an infusion, decoction, sirup or paste, is administered as
a treatment for sore throat, colds, bronchial catarrh. It is taken to
relieve fever, cystisis, gonorrhea, edema, liver and abdominal
troubles. And it is said to counteract alcohol intoxication.
The seed powder is an ingredient in a paste given to relieve ague.
A gum that exudes from the wounded trunk is employed in India for
treating diarrhea and genito-urinary ailments. It is diuretic and
demulcent. The roots are used against toothache. The pollen yields an
estrogenic principle, estrone, and has a gonadotropic effect on young
rats.
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