Apple of Sodom (Calotropis procera). Leaves, flowers and fruits.

Apple of Sodom - Calotropis procera

Calotropis procera is a species of flowering plant in the family Apocynaceae that is native to Northern and Tropical Africa, Western Asia, South Asia and Indochina (mainland Southeast Asia). It typically reaches a height between 6 feet (1.8 m) to 8 feet (2.4 m), and rarely to as high as 15 feet (4.6 m), and grows in sunny to partly-shaded habitats such as disturbed and overgrazed lands, rangeland, roadsides, river flats and coastal dunes. Its green fruits contain a toxic milky sap that is extremely bitter and turns into a latex-like substance, which is resistant to soap.

Common names for the plant include Apple of Sodom, Sodom apple, roostertree, king's crown, small crownflower, giant milkweed, rubber bush, and rubber tree. The names "Apple of Sodom" and "Dead Sea Apple" stem from the ancient authors Josephus and Tacitus, who described the plant growing in the area of biblical Sodom. Although not native to the New World, the plant (and other related milkweed species) has been cultivated, and feeds monarch butterfly caterpillars, in places such as California, Hawaii and the island of Puerto Rico. In Arabic, it is known as al-ashkhar.

Calotropis (Calotropis procera (Aiton) W. T. Aiton) is a spreading shrub or medium-sized tree reaching 2.5 to 6 m in height. It has a deep taproot, 3-4 m deep, and a secondary root system with woody lateral roots that may rapidly regenerate adventitious shoots when the plant is injured. The stems are crooked and covered with a fissured corky bark. The grey-green leaves are 15-30 cm long and 2.5-10 cm broad and have a succulent and waxy appearance, hence the name procera, which means wax in latin. The flowers are pentamerous, small, cream or greenish white at the base and purple violet at the extremity of the lobes. The fruit is a fleshy and inflated, up to 10 cm or more in diameter. The plant juice is poisonous.

Calotropis procera originated from the Afro-Asian monsoonal regions. It spread on an arc expanding from north western Africa (Mauritania, Senegal), through the Arabian Peninsula and Middle-East to the Indian subcontinent. It was introduced to subtropical America, the Mascarene Islands, drier parts of Australia and probably South-East Asia.

Calotropis is found from sea level up to an altitude of 1300 m in semi-arid conditions (150 to 1000 mm annual rainfall) on sandy soils. However, it can withstand a wide range of soil textures. It is tolerant of soil salinity and of beach front salt spray. On excessively drained soils, it can withstand up to 2000 mm annual rainfall. It quickly becomes established in open habitats with little competition, along degraded roadsides, lagoon edges and in overgrazed native pastures and rangelands. When calotropis is damaged, it readily develops suckers from the roots. Calotropis seeds are spread by wind and animals and may be transported long distances in flood waters.

The flower shoots are eaten young and raw. The leaves are occasionally eaten. The leaves are used for making an alcoholic drink. In Ethiopia the sap is added to milk to help it coagulate. The leaves have been used as a soup ingredient in sauces.

Calotropis procera is a multipurpose tree. The stems yield a fibre useful for making ropes, bags, nets and paper. The seeds contain a white silky floss that is a potential silk replacer. The wood is valuable as a timber and fuel. The milky sap (latex) is renowned for its ethno-medicinal properties and as a food, particularly as a coagulation agent for cheese making in West Africa. Calotropis yields 90 t of biomass twice a year and is a potential source of renewable energy.

Calotropis is also used as fodder. Young pods, senescing leaves and flowers can be fed to goats, camels, and sheep (more rarely to cattle) in times of scarcity. The latex contains toxic components that may be harmful to livestock.

The stem is source of strong and durable fibre used in making ropes, bow strings, fishing nets, paper, pulp, etc. The seed capsules, on the other hand, are used as stuffing material in mattresses. The stems further produce good charcoal and is termite resistant. It is used for roofing and building hats. Mudar Gummi, a rubber material, is also obtained from Auricula tree.

Some biblical commentators believe that the Sodom apple may have been the poisonous gourd (or poison-tasting gourd) that led to "death in the pot" in the Second Book of Kings (2 Kings 4:38–41). In this story, a well-meaning servant of the prophet Elisha gathers herbs and a large quantity of the unknown gourds, and casts them into the pot. After the outcry from the band of prophets, Elisha instructs them to cast flour into the stew pot, and they are saved. In 1938, botanists Hannah and Ephraim HaReuveni, authors of "The Squill and the Asphodel" (and parents of Noga HaReuveni), speculated that Jeremiah's ar‘ar/arow‘er was the Sodom apple. The fibre of the Sodom apple may have been used for the linen of the high priests.

The fruit is described by the Roman Jewish historian Josephus, who saw it growing near what he calls Sodom, near the Dead Sea: "...as well as the ashes growing in their fruits; which fruits have a color as if they were fit to be eaten, but if you pluck them with your hands, they dissolve into smoke and ashes."

Sodom apple is listed in the Mishnah and Talmud. The fibers attached to the seeds may have been used as wicks. However the Mishnah forbids this for the Sabbath: "It may not be lighted with cedar-bast, nor with uncombed flax, nor with floss-silk, nor with willow fiber, nor with nettle fiber. – Sabbath Chapter 2"

In his Biblical Researches in Palestine, American biblical scholar Edward Robinson describes it as the fruit of the Asclepias gigantea vel procera, a tree 10–15 feet high, with a grayish cork-like bark called 'osher by the Arabs. He says the fruit resembled "a large, smooth apple or orange, hanging in clusters of three or four." When "pressed or struck, it explodes with a puff, like a bladder or puff-ball, leaving in the hand only the shreds of the thin rind and a few fibers. It is indeed filled chiefly with air, which gives it the round form; while in the center a small slender pod runs through it which contains a small quantity of fine silk, which the Arabs collect and twist into matches for their guns."

Bedouins of the Sinai and Negev traditionally made use of the fibers of this plant for making skull-caps (tagiyah).

Known as Sodom's Apple (Al Ashkhar) in the United Arab Emirates, it is a common desert shrub with a wide range of medicinal applications in traditional Bedouin medicine. It has been linked to a number of cases of poisoning and corneal damage caused by children unknowingly touching its sap and then their eyes. Bedouin have long held that the plant causes blindness if contact is made with the eyes and any part of the plant. Its roots were traditionally burned and used as a component of gunpowder by Bedouin in the Trucial States.

The plant is known to occur throughout the tropical belt and is also common in the West Indies (e.g. Jamaica, Puerto Rico), where the locals know it as "pillow cotton". When the ripe "apples" burst, the fibrous contents are ejected along with the seeds.

The giant milkweed is used for fibre and medicine in Southern Africa, but it rapidly invades subsistence agricultural fields reducing yields. The plant is poisonous if eaten by livestock. It thrives in the hot northern regions of Limpopo Province. This plant is also found along road verges and in drainage lines.

In Australia, it is a weed of Western Australia, the Northern Territory, South Australia and Queensland. It is thought to have arrived in the Northern Territory via the seeds which have tufts of silky hairs: the silky material (originating in Africa or Asia) having been used as padding in camel saddles. In the Northern Territory, it is found on alluvial plains, ephemeral watercourses and run-on areas. It also occurs on red earth plains and heavy soil plains.

The milky sap contains a complex mix of chemicals, some of which are steroidal heart poisons known as "cardiac aglycones". These belong to the same chemical family as similar ones found in foxgloves (Digitalis purpurea).

The plant contains steroidal components that are the cause of its toxicity. In the case of the Calotropis glycosides, their names are calotropin, calotoxin, calactin, uscharidin and voruscharin.

Compounds derived from the plant have been found to have emetic-cathartic and digitalic properties. The principal active compounds are asclepin and mudarin. Other compounds have been found to have bactericidal and vermicidal propertie. The root bark is an emetic. An infusion of bark powder is used in the treatment and cure of leprosy and elephantiasis. It is inadvisable to use bark that has been kept for more than a year. The extremely poisonous roots are used in the treatment of snakebites. The leaves are used for the treatment of asthma. The milky sap is used as a rubefacient and is also strongly purgative and caustic. 

The latex is used for treating ringworm, guinea worm blisters, scorpion stings, venereal sores and ophthalmic disorders, it is also used as a laxative. Its use in India in the treatment of skin diseases has caused severe bullous dermatitis leading sometimes to hypertrophic scars. The local effect of the latex on the conjunctiva is congestion, epiphora and local anaesthesia. The latex contains a proteolytic enzyme called caloptropaine.

The flower is digestive and tonic. It is used in the treatment of asthma and catarrh. The twigs are applied for the preparation of diuretics, stomach tonic and anti-diarrhoetics and for asthma. Also used in abortion, as an anthelmintic, for colic, cough, whooping cough, dysentery, headache, lice treatment, jaundice, sore gums and mouth, toothache, sterility, swellings and ulcers.

Source:
https://en.wikipedia.org/wiki/Calotropis_procera
https://pfaf.org/USER/Plant.aspx?LatinName=Calotropis+procera
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