Tussar silk (alternatively spelled as tussah, tushar, tassar, tussore, tasar, tussur, or tusser, and also known as (Sanskrit) kosa silk) is produced from larvae of several species of silkworms belonging to the moth genus Antheraea, including A. assamensis, A. paphia, A. pernyi, A. roylei, and A. yamamai. These silkworms live in the wild forests in trees belonging to Terminalia species and Shorea robusta, as well as other food plants such as jamun and oak found in South Asia, eating the leaves of the trees on which they live. Tussar silk is valued for its rich texture and natural, deep-gold colour, and varieties are produced in many countries, including China, India, Japan, and Sri Lanka. To kill the silkworms, the cocoons are dried in the sun. A variation of the process exists in which the silkworms are allowed to leave before the cocoons are soaked in boiling water to soften the silk, and then the fibers are reeled. Single-shelled, oval-shaped cocoons are collected and then boiled to extract the silk yarn. Boiling is a very important part in the manufacturing of silk, as it softens the cocoon and makes the extraction of silk easier. In conventional sericulture, the cocoons are boiled with the larvae still inside, but if the cocoons are boiled after the larvae have left them, the silk made is then called "nonviolent silk" or "Ahimsa silk". In China, the silks are given different names when silkworms are reared on different plants, as the diet of the silkworms has an effect on the quality of the silk. For example, silk from larvae on the wild mulberry is called zhe, while those on the oak Quercus dentata produce hu. Tussar silk is considered more textured than cultivated Bombyx or "mulberry" silk, but it has shorter fibres, which makes it less durable. It has a dull, gold sheen. As most of the cocoons are collected from the forest, it is considered by many as a forest product. India is the second-largest producer of tussar silk, and the exclusive producer of Indian tussar (also known as tropical tussar), which is largely tended to by tribals.
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