The coveted secret of silkworm cultivation began 5000 years ago in China. Sericulture (the production of raw silk by raising silkworms) spread to Korea and later to Japan and southern Asia. During the eleventh century European traders stole several eggs and seeds of the mulberry tree and began rearing silkworms in Europe. Sericulture was introduced into the Southern United States in colonial times, but the climate was not compatible with cultivation.
Today, silk is cultivated in Japan, China, Thailand, Spain, France, and Italy, although artificial fibers have replaced the use of silk in much of the textile industry. The silk industry has a commercial value of $200-$500 million annually. One cocoon is made of a single thread about 914 meters long. About 3000 cocoons are needed to make a pound of silk.
To gather silk from cocoons, boil intact cocoons for five minutes in water turning them gently. Remove from the water and using a dissecting needle or similar tool, begin to pick up strands. When you find a single strand that comes off easily, wind the silk onto a pencil. Several of these strands are combined to make a thread.