silkworms

I have been laboring over my computer trying to organize my couple thousand photos and came across photos of my silkworm experience in, oh, 1983 I think. I did show them to the Atlanta guild earlier this year, and in the interval of ugly computer issues, was concerned they might be lost. But here they are! It was a fun spring project, but it was a lot of work too. It was supposed to last about 26 days from hatching to spinning, but my worms liked me so much they hung around an extra two weeks. As soon as the mulberry trees started to leaf out, I brought my two small packs of eggs from the frig to bring to room temperature. I had a yellow silk strain and a white silk strain of eggs. It takes somewhere between 6 and 20 days for the eggs to hatch. You can see cottonballs next to the eggs. These are moistened with water to add humidity to their environment. Here they are at four days old. You can barely see them still. Notice a dark thing at the top of the left hand leaf--there's one! They are munching on mulberry leaves which I picked daily, washed, and kept fresh in the frig in a vase of water. All the leaves had to be dry before they were fed to the worms. At 18 days they have grown considerably. At 23 days, you can see some sluffed skins on the lower right leaf. The worms go through four moltings in their liftimes as worms. The five time periods between molts are called instars. Here is a boxful at 36 days. I had to empty the box every day and remove the frass (their poop). You can imagine I was beginning to think I would be doing this forever! Carefully, I had to lift the worms out and change their paper. The silkworm's skin is so delicate from thousands of years of selective breeding for silk (not for impermeable skin), that you have to be very careful. I would lift them out of the box on top of the paper towel that was their floor, put new paper in the box, and then used a utensil to scoop them back into the box. Here they are while I am cleaning their home. This amazing worm is over four inches long and bigger around than my forefinger. After I took one photo of him/her, he/she raised his/her head. So all this time, the worms had happily stayed in shoe boxes. Then they began a-wandering, looking for a place to hunker down and spin. I know the feeling. Once the worms find a good spot, the process takes about three days to spin the complete cocoon and turn into a pupa. It takes around three weeks before metamorphosis to moth is complete. What beautiful cocoons! Here are a couple of moths emerging at about the same time. You can see a brown spot in front of one of the cocoons. I was told this is the acid that is excreted from the worm to break out of the cocoon. But I have read other explanations as well. This little moth, just came out of its cocoon and is spreading its wings after being cramped for a good while. By flapping the wings, blood is pumped into them and they get larger and fuller after being cramped for so long in a tiny space. Domesticated silkworms have lost the ability to fly over the millenia, but there are still species in the wild that fly and spin beautiful silks in shades of brown. OK. Now those of you who are sensitive... don't look. This is the high point of a silk worm's life: mating, abdomen to abdomen. Within two days, the female will lay her eggs carefully in a single layer. Both male and female moths die soon after. They eat nothing for the rest of their lives after they begin spinning. The sad part is that in order to have a continuous strand of silk (about a mile long) the cocoons must be heated so the moths are "stifled"--a polite way of saying they are killed. Once the moth emerges, the single filament is broken into many pieces, and although the quality is the same, the more textured threads and yarns made from broken silk are not as highly prized. Here are some of my cocoons ready to be heated. Here are some of the yarns I have spun from silk (not from my own cocoons). But the thread you see on the funny looking niddy noddy is what I reeled from 8 cocoons--that's the filament from eight cocoons creating the thickness of that thread. Also shown are a brick of silk and mawata (the "hankie" looking thing). If you are interested in a quick and easy factual read on more details of the life cycle, check out this school project of some third graders in California!