A couple days ago I stopped feeding the silkworms to force them to cocoon. I had been basically denuding the mulberry tree a neighbor had generously allowed me to prune from, and was ready for the silkworms to be DONE. (And, to be clear, they were ready; they would happily have eaten more but did not need to. They had been in the fifth instar for 8-9 days.)
The process from there is simple: after food is withdrawn, the caterpillars will move off the leaves (or what used to be the leaves) and start climbing up. I made them a pile of toilet paper tubes to cocoon in, because they are cheap and plentiful (we collected them for a few months). They climb up and look around for a good spot, trying out a few tubes and spots until they find one that feels just right.
The little guys find a tube they like and make a silk mesh to hang themselves in before they start the cocoon in earnest. Also, one last poop, for posterity:
And another one, this one in the process of expelling the contents of its gut.
There are a hundred different ways of making places for silkworms to cocoon. Professionals and more serious growers put them in a folded chickenwire mesh structure. Lots of people use egg cartons (we have another use for those). Plenty of people use toilet paper tubes, mostly set vertically in a box. I put mine horizontally and made a stack. They don't seem to mind too much.
A few of the caterpillars started climbing up on the toilet paper tubes I gave them right away. But nobody chose a spot until Sunday morning. This is one of the first cocoons, a day later:
This is one of the Ken's Yellow cocoons. The colour is just in the gum on the outside of the silk: if you process it normally, you will end up with white silk. Or you can leave the gum on and have a stiff, yellow silk.
It takes a silkworm about 2 days to spin a complete cocoon, and they stay in the cocoon for about a week before emerging. I don't want these guys to emerge as moths, but I do want them to spin as much silk as possible, so on Friday I will be baking them in the oven to kill them in place. Then I can reel the silk off the cocoons.
very cool. i'm hunting for a mulberry tree so that i can raise some silkworms this year. i have some plans for the cocoons as is, so i probably won't reel them. the curricula moth would be a really neat worm to raise for their cocoons, but i think they might be wild moths.