Wild silks have been known and used in many countries from early times, although the scale of production is far smaller than that from cultivated silkworms.

Background

Wild silk

Silk

Silk is a natural protein fiber, some forms of which can be woven into textiles. The best-known type of silk is obtained from the cocoons of the larvae of the mulberry silkworm Bombyx mori reared in captivity...

 should not be confused with the very rare sea silk

Sea silk

Sea silk is an extremely fine, rare and valuable fabric produced from the long silky filaments or byssus secreted by a gland in the foot of several bivalve molluscs by which they attach themselves to the sea bed....

 which is produced from the fibres or byssus

Byssus

Byssus means both a silky filament by which certain molluscs attach themselves to hard surfaces, and a rare fabric, also called sea silk and its fibre source.-Word:...

 produced by the seashell Pinna nobilis

Pinna nobilis

Pinna nobilis, common name the "noble pen shell" is a species of pen shell, a large marine bivalve mollusc in the family Pinnidae, the 'pen shells'....

and related species.

Commercially reared silkworms of the species Bombyx mori

Bombyx mori

The silkworm is the larva or caterpillar of the domesticated silkmoth, Bombyx mori . It is an economically important insect, being a primary producer of silk...

(Linnaeus, 1758), are normally killed before the pupae emerge either by pricking them with a needle or dipping the cocoons into boiling water, thus allowing the whole cocoon to be unravelled as one continuous thread. This allows a much finer cloth to be woven from the silk.

There are more than 500 species of wild silkworms in the world although only a few are used to produce cloth. They usually produce a tougher and rougher silk than that from domesticated Bombyx mori silkworms. Wild silks are usually harvested after the moths have left the cocoons, cutting the threads in the process so that there is not one long thread as with domesticated silkworms.

Wild silks tend to be more difficult to bleach and dye than silk from Bombyx mori, but most have naturally attractive colours, particularly the rich golden sheen of the silk produced by the muga

Muga

The Muga is a river in Catalonia which rises in the Alberes mountains of the eastern Pyrenees and enters the sea at the Gulf of Roses.The river is 58 km long with its source below the summit of Montnegre...

 silkworm from Assam

Assam

Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...

 and is often known as Assam silk

Assam Silk

Assam silk denotes the three major types of indigenous wild silks produced in Assam—golden Muga, white Pat and warm Eri silk. The Assam silk industry, now centered in Sualkuchi, is a labor intensive industry.-Muga silk:...

.

The cocoon shells of Wild Silk moths are toughened or stabilized either by tanning (cross-linking) or by mineral reinforcements (e.g. calcium oxalate). Recently, a new method has been developed, demineralizing, which can remove the mineral reinforcements present in wild silks and enables wet reeling like the commercial silkworm Bombyx mori.

Wild silk industry in India

Wild silks are often referred to in India as 'Vanya' silks:

"The term 'Vanya' is of Sanskrit

Sanskrit

Sanskrit , is a historical Indo-Aryan language and the primary liturgical language of Hinduism, Jainism and Buddhism.Buddhism: besides Pali, see Buddhist Hybrid Sanskrit Today, it is listed as one of the 22 scheduled languages of India and is an official language of the state of Uttarakhand...

 origin, meaning untamed, wild, or forest-based. Muga, Tasar, and Eri silkworms are not fully tamed and the world lovingly calls the silks they produce as 'wild silks'."

"India produces four kinds of silk: mulberry, tassar, muga and eri. The silkworm Bombyx mori is fed on mulberry leaves cultivated in plantations. Silkworms are also found wild on forest trees, e.g Antheraea paphia which produces the tassar silk (Tussah). Antheraea paphia feeds on several trees such as Anogeissus latifolia

Anogeissus latifolia

Anogeissus latifolia is a species of small to medium-sized tree native to the India, Nepal, Myanmar, and Sri Lanka. Its common names are axlewood , bakli, dhau, dhawa, dhawra, or dhaora , takhian-nu , and raam .It is one of the most useful trees in India...

, Terminalia tomentosa, T. arjuna (Terminalia arjuna

Terminalia arjuna

Terminalia arjuna is a tree of the genus Terminalia.-Description:...

), Lagerstroemia parviflora and Madhuca indica. Wild silkworm Antheraea assamensis produces muga silk, and another wild silkworm Philosamia synthia ricini (= Samia cynthia

Samia cynthia

The Ailanthus silkmoth is a saturniid moth, used to produce silk fabric but not as domesticated as the silkworm, Bombyx mori. The moth has very large wings of 113-125 mm, with a quarter-moon shaped spot on both the upper and lower wings, whitish and yellow stripes and brown background...

) produces eri silk

Eri silk

Eri Silk comes from the worm Samia cynthia ricini, found in North East of India and some parts of China and Japan. The name Eri is derived from the Assamese word ‘era’, which means castor as the silkworm feeds on castor plants. One of the common names, the 'Ailanthus Silk moth', refers to the host...

. The estimated annual production of tassar silk is 130 tonnes. Production of other types of silk exceeds 10 000 tonnes (Gupta 1994)."

The eri silk worm from India feeds on the leaves of the castor

Castor

Castor derives from the , meaning "beaver", or "he who excels". It originally referred to Castor, one of the Dioscuri/Gemini twins of Graeco-Roman mythology.Castor or CASTOR may also refer to:-Science and technology:...

 plant. It is the only completely domesticated silkworm other than Bombyx mori. The silk is extremely durable, but cannot be easily reeled off the cocoon and is thus spun like cotton or wool.

History

Wild silk threads have been found and identified from two Indus River

Indus River

The Indus River is a major river which flows through Pakistan. It also has courses through China and India.Originating in the Tibetan plateau of western China in the vicinity of Lake Mansarovar in Tibet Autonomous Region, the river runs a course through the Ladakh district of Jammu and Kashmir and...

 sites, Harappa

Harappa

Harappa is an archaeological site in Punjab, northeast Pakistan, about west of Sahiwal. The site takes its name from a modern village located near the former course of the Ravi River. The current village of Harappa is from the ancient site. Although modern Harappa has a train station left from...

 and Chanhu-daro, dating to c. 2450-2000 BCE. This is roughly the same period as the earliest evidence of silk use in China, which is generally thought to have had the oldest silk industry in the world. The specimens of threads from Harappa appear on Scanning electron microscope

Scanning electron microscope

A scanning electron microscope is a type of electron microscope that images a sample by scanning it with a high-energy beam of electrons in a raster scan pattern...

 analysis to be from two different species of silk moth, Antheraea mylitta and A. assamensis, while the silk from Chanhu-daro may be from a Philosamia species, (Eri

Eri

Eri can refer to:* Eri , a Japanese feminine given name* Erie International Airport in Erie, Pennsylvania, IATA airport code* Eri, a biblical figure* Eri , the progenitor of the Nri-Igbo* Eri, a type of silk from Assam, India...

 silk), and this silk appears to have been reeled.

Wild silks were in use in China from early times. Moreover, the Chinese were aware of their use in the Roman Empire and apparently imported goods made from them by the time of the Later Han Dynasty in the 1st to 3rd centuries CE.

There are significant indications in the literature that wild silks were in use in Persia and in Greece by the late 5th century BCE, apparently referred to as "Amorgina" or "Amorgian garments" in Greece.

Pliny the Elder

Pliny the Elder

Gaius Plinius Secundus , better known as Pliny the Elder, was a Roman author, naturalist, and natural philosopher, as well as naval and army commander of the early Roman Empire, and personal friend of the emperor Vespasian...

, in the 1st century CE, obviously had some knowledge of how wild silkworms' cocoons were produced and utilised on the island of Kos

Kos

Kos or Cos is a Greek island in the south Sporades group of the Dodecanese, next to the Gulf of Gökova/Cos. It measures by , and is from the coast of Bodrum, Turkey and the ancient region of Caria. Administratively the island forms a separate municipality within the Kos peripheral unit, which is...

, even though his account included some fanciful ideas.

List of some wild silk moths and their silk

• Antheraea assamensis
  Antheraea assamensis
  The Muga Silkworm is the larva of the Assam Silkmoth , a moth of the Saturniidae family. It is found in India , Burma and Sundaland....
  
  (Helfer, 1837). - From Assam
  Assam
  Assam , also, rarely, Assam Valley and formerly the Assam Province , is a northeastern state of India and is one of the most culturally and geographically distinct regions of the country...
  
  . Its silk has a beautiful glossy golden hue which improves with age and washing. Is never bleached or dyed and is stain resistant. Was reserved for the exclusive use of royal families in Assam for 600 years.
• Antheraea mylitta (Drury, 1773). - The "tasar" silkworm.,
• Antheraea pernyi
  Antheraea pernyi
  Antheraea pernyi, the Chinese Tussah Moth , also known as Temperate Tussah Moth, is a large moth in the family Saturniidae. Antheraea roylei is an extremely close relative and the present species might actually have evolved from ancestral A. roylei by chromosome rearrangement.They are originally...
  
  (Guénerin-Méneville, 1855). - the Chinese Tussah Moth. The colour and quality of the silk depends on the climate and soil.
• Antheraea polyphemus
  Antheraea polyphemus
  The Polyphemus Moth is a North American member of the family Saturniidae, the giant silk moths. It is a tan colored moth, with an average wingspan of 15 cm . The most notable feature of the moth is its large, purplish eyespots on its two hindwings...
  
  . - Has the most potential of any North American silkworms.
• Antheraea yamamai
  Antheraea yamamai
  The Japanese Silk Moth or Japanese Oak Silkmoth is a moth of the Saturniidae family. It is endemic to Japan, but has been imported to Europe for silk production and is now found in South-Eastern Europe, mainly in Austria, North-Eastern Italy and the Balkan...
  
  (Guénerin-Méneville, 1861). - The "tensan" silk moth. Has been cultivated in Japan for more than 1000 years. It produces a naturally white silk but does not dye well, though it is very strong and elastic. It is now very rare and expensive.
• Anisota senatoria
  Anisota senatoria
  The Orangestriped oakworm is a Nearctic member of the family Saturniidae and subfamily Ceratocampinae. It is one of the more common Saturniids, reaching pest status occasionally in the northern parts of its range...
  
  (J. E. Smith, 1797). - "Orange-tipped oakworm moth." North American moth.
• Automeris io
  Automeris io
  The Io Moth is a very colorful North American moth in the Saturniidae family. It ranges from the southeast corner of Manitoba and in the southern extremes of Ontario, Quebec, and New Brunswick in Canada, and in the US it is found from Montana, North Dakota, South Dakota, Nebraska, Colorado, New...
  
  . - (Fabricius, 1775). North American moth.
• Bombyx mandarina
  Bombyx mandarina
  Bombyx mandarina, the Wild Silkmoth, is an insect from the moth family Bombycidae. It is the closest relative of Bombyx mori the Domesticated Silkmoth or "silkworm" . Unlike the domesticated relative which is unable to fly or indeed persist outside human care, the Wild Silkmoth is a fairly ordinary...
  
  (Moore). Possible wild form of B. mori.
• Bombyx sinensis - from China. Prolific but small cocoons.
• Callosamia promethea
  Callosamia promethea
  The Promethea Silkmoth , is a member of the Saturniidae family of moths.-Description:Males have dark brownish-black wings with a faint white postmedian line and pinkish coloring near the apical spot. Females are bright reddish-pink or a brownish color with well-developed reniform spots. Both...
  
  . - North American
• Gonometa
  Gonometa
  Gonometa is a genus of Moth in the family Lasiocampidae....
  
   postica Walker. - From the Kalahari region.
• Gonometa
  Gonometa
  Gonometa is a genus of Moth in the family Lasiocampidae....
  
   rufobrunnae Aurivillius. - Feeds on the Mopane
  Mopane
  The mopane or mopani tree grows in hot, dry, low-lying areas, in elevation, in the far northern parts of southern Africa, into South Africa, Zimbabwe, Mozambique, Botswana, Zambia, Namibia, Angola and Malawi. The tree only occurs in Africa and is the only species in genus Colophospermum...
  
   tree in southern Africa
• Hyalophora cecropia
  Hyalophora cecropia
  The Cecropia Moth is North America's largest native moth. It is a member of the Saturniidae family, or giant silk moths. Females with a wingspan of 160 mm or more have been documented. It is found as far west as the Rocky Mountains and north into the maritime provinces of Canada...
  
  . - North American. Quality of the silk depends on food source.
• Samia cynthia
  Samia cynthia
  The Ailanthus silkmoth is a saturniid moth, used to produce silk fabric but not as domesticated as the silkworm, Bombyx mori. The moth has very large wings of 113-125 mm, with a quarter-moon shaped spot on both the upper and lower wings, whitish and yellow stripes and brown background...
  
  (Drury, 1773). - The Ailanthus Silkmoth - A somewhat domesticated silkworm from China. Introduced into North America. The eri
  Eri
  Eri can refer to:* Eri , a Japanese feminine given name* Erie International Airport in Erie, Pennsylvania, IATA airport code* Eri, a biblical figure* Eri , the progenitor of the Nri-Igbo* Eri, a type of silk from Assam, India...
  
  silkmoth from Assam is a subspecies of this moth (S. cynthia ricini). It produces a white silk which resembles wool mixed with cotton, but feels like silk.

External links

• "Raw & Organic Silk: Facts behind the Fibers" http://organicclothing.blogs.com/my_weblog/2007/03/raw_organic_sil.html
• "South Africa: Development of the wild silk industry." http://www.unido.org/index.php?id=6046
• "Walter Sweadner and the Wild Silk Moths of the Bitteroot Mountains. By Michael M. Collins. http://carnegiemuseums.org/cmag/bk_issue/1997/janfeb/feat2.htm
• "Kalahari Wild Silk" By Amy Schoeman. http://www.holidaytravel.com.na/index.php?fArticleId=499
• "Anisota senatoria' http://www.silkmoths.bizland.com/sasenato.htm
• "Orange-tipped oakworm moth." http://www.butterfliesandmoths.org/species?l=3347