The date palm (Phoenix dactylifera L.) is one of about 14 recognized species of the genus Phoenix, and it is one of the most important crops in the world today. The genus is widespread in tropical and subtropical regions of Africa and southern Asia. The date palm is the tallest of the species, reaching over 30 meters (~100 feet) in height; the palm plant has multiple clustering trunks, although often cultivators clip off the offshoots for propagation elsewhere. Date palms come in male and female plants, and both are required for fertilization. The leaves of a date palm are pinnate and V-shaped, measuring between 3-6 m (10-20 ft) in length.
There are approximately 3,000 different date palm cultivar names used for date palms in the world, although scholars believe many are probably synonyms. Date cultivars are grouped by the texture of their fruit under normal ripening conditions, as soft, semi-dry or dry. Cultivars are often also grouped by when their fruit ripen: early, mid-season and late.
Date Fruit
Date fruits come in a variety of colors from honey and amber through dark reds, browns and blacks. Domesticated date palm fruits vary in shape and size, from 2-60 grams (.7-2.1 ounces) in weight and from 40-100 millimeters (1.5-4 inches) in size, and the fruits grow significantly larger in P. dactylifera than other Phoenix species.
Dates reach their full fruit-bearing potential at about 10 years of age, and on average, continue to bear fruit for 40-50 years. Some dates can continue producing fruit for 100 years, but as such trees grow so tall and the fruit becomes more and more difficult to reach, they are often cut down. Date palms flower typically once a year, although in very wet years they can flower twice.
Benefits of Dates
Date fruits are high-energy and can be picked fresh and eaten, as well as easily sun-dried for long-term storage. They can be pressed into a date cake for easy transportation; made into syrup and fermented into date wine (laqmi) or vinegar; and the pits can be burned as fuel, which produces an edible stock for animals.
The old Akkadian word for ripened and plucked dates is suluppû; dried or perhaps fresh dates were called uhinnu in cuneiform script. Butê cakes were made from a combination of dates, pomegranates, raisins and figs, and in Neo-Babylonian (ca 1000 BC) times, giddê was a cake made from dates, emmer wheat and sesame.
In deserts, date palms grow in oases, where the trees help create and sustain a micro-climate suitable for agriculture and livestock raising. The stems of the trees can be used as construction wood; the leaves' midribs are suitable for fencing material and the leaves themselves can be woven into baskets.
Domestication History
Date palms were likely originally domesticated in the Fertile Crescent region of Mesopotamia, approximately 7,000 years ago. The domestic date palm was produced from a wild version of the same name, some of which have been found today in North Africa and the Middle and Near East. Wild dates can hybridize with cultivars, and are morphologically quite similar to the domesticated forms. The main difference is size of the fruit.
Evidence found in Mesopotamia associated with domesticated palms includes the planting of date groves, date palms planted by gender, and free-flowing irrigation and other water management structures. Additional evidence is in engravings on cylinder seals and texts illustrating the date palm in Sumerian Mesopotamia beginning ca 2500 BC.
Sites with early date palm occurrences include Tepe Gaz Tavila in Iran (5400-4800 BC); Tell el-Ouelli (5th millennium BC) and Eridu (4th millennium BC) in Iraq; Teleilat Ghassul (3700-3500 BC and Jericho (3200 BC) in Palestine; Mohenjo Daro (3,000 BC) in Pakistan; and the Dilmun culture sites of Failaka (2000 BC) in Kuwait and Qala't al Bahrain (1475 BC) in Bahrain.
Sources
This glossary entry is a part of the About.com guide to Plant Domestication, and the Dictionary of Archaeology.
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