Silk is made by silkworms. These are the caterpillars of a Chinese moth, which feed on the leaves of the mulberry tree. They are now extinct in the wild, but are reared in large numbers by the silk industry. It was in China around 5,000 years ago that humans first discovered how to make a luxury fabric out of an unpromising insect secretion. In recent centuries, the secrets of silk production spread around the world and, wherever the climate was suitable, mulberry trees were planted to feed silkworms.
When fully grown and ready to become a chrysalis - which in turn will become an adult moth - a silkworm spins a fibrous cocoon around itself for protection. The silk of the cocoon is secreted as a continuous filament - up to a mile long - by special glands in the silkworm's head. The chrysalis is killed by heat while still in the cocoon because if the adult moth were allowed to emerge from the cocoon naturally the fibre would be broken into pieces, making it less suitable for manufacture.
To extract the silk, the cocoons are softened in hot water, allowing the filaments to be unwound, and combined to make yarn suitable for knitting or weaving. One silkworm produces only about 0.2 grams of raw silk, so it takes huge numbers to produce silk in any quantity. Vast piles of dead chrysalises are produced as a "byproduct". These are sometimes composted or used as food for farmed fish, for pigs or even for humans.
A small number of silk moths are allowed to live and emerge naturally from the cocoon, but only as breeding stock for the next generation of silkworms. The modern silk industry is highly industrialised, producing up to 100 kg of raw silk per hectare per year on good agricultural land. This represents the deaths of around half a million silkworms, consuming a total of about 12 tons of mulberry leaves during their short lives.
The leaves are harvested from small trees that do not bear fruit. Although highly mechanised, the process still requires many human workers, usually women and children, to extract the fibre from the cocoons. These workers are often required to work in poor conditions, for low pay.
There are now many excellent vegetable and synthetic fibres that have the same attractive qualities as silk, but without the cruelty - and also less expensive. Silk production exploits animals (silkworms), people (silk factory workers), and the environment (land which could be left for wildlife or used to grow food), so vegans do not use silk.
When fully grown and ready to become a chrysalis - which in turn will become an adult moth - a silkworm spins a fibrous cocoon around itself for protection. The silk of the cocoon is secreted as a continuous filament - up to a mile long - by special glands in the silkworm's head. The chrysalis is killed by heat while still in the cocoon because if the adult moth were allowed to emerge from the cocoon naturally the fibre would be broken into pieces, making it less suitable for manufacture.
To extract the silk, the cocoons are softened in hot water, allowing the filaments to be unwound, and combined to make yarn suitable for knitting or weaving. One silkworm produces only about 0.2 grams of raw silk, so it takes huge numbers to produce silk in any quantity. Vast piles of dead chrysalises are produced as a "byproduct". These are sometimes composted or used as food for farmed fish, for pigs or even for humans.
A small number of silk moths are allowed to live and emerge naturally from the cocoon, but only as breeding stock for the next generation of silkworms. The modern silk industry is highly industrialised, producing up to 100 kg of raw silk per hectare per year on good agricultural land. This represents the deaths of around half a million silkworms, consuming a total of about 12 tons of mulberry leaves during their short lives.
The leaves are harvested from small trees that do not bear fruit. Although highly mechanised, the process still requires many human workers, usually women and children, to extract the fibre from the cocoons. These workers are often required to work in poor conditions, for low pay.
There are now many excellent vegetable and synthetic fibres that have the same attractive qualities as silk, but without the cruelty - and also less expensive. Silk production exploits animals (silkworms), people (silk factory workers), and the environment (land which could be left for wildlife or used to grow food), so vegans do not use silk.
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