I keep a Worm Factory(R) in my garage, which has been in constant use for over a year. I've had a couple of exoduses due to overheating (exothermic decomposition- too much green stuff) in the past and had to round up the survivors and wrangle them back into the bin. They were able to squirm pretty far away. This holocaust is different. The escaping worms didn't have the strength to crawl further than a foot from the bin before dying. I have a cascade of dried, dead worms running down the corners of the trays - and they made their escape, not from the TOP tray, but the next one down.

Yesterday, I looked at the working tray to see if there was room for another dose of scraps. It appeared rather dry, and I saw no worm activity, so I dug down a little to see if that was dry too. Just below the surface the compost was suffused with a light grey-blue powdery mold, and this also seemed rather dry. I liberally misted the working tray with water, and decided to allow the moisture to soak in for the rest of the day. When I looked at it this morning... Horror!

I've added nothing novel to my bin recently. Never any animal products, no cheeses, no citrus. I feed primarily coffee grounds (about a cup per day), vegetable trimmings (one or two meals worth per day), aging wheat grass (1 pint container per week, greens snipped up and roots and coir shredded), and rose blossoms (about 9-12 per week, mostly pulled apart into individual petals), with the occasional bundle of greens or herbs that were neglected in the fridge for too long and/or shredded newspaper.

The tray did not feel overly warm to the touch yesterday, nor does it today. This is the ninth day of the recent heat wave here in the west (northern California) and temperatures have actually been coming down the last three days, so I don't think it's environmental heat. Besides, if it was just heat, they'd have traveled some after their escape. These guys were dying AS they escaped. They didn't travel anywhere.

Are there molds that poison worms? Did I wash a poisonous mold down onto the worms avoiding it by hiding in the tray below? I have not yet disassembled the entire setup to see if ANY worms survived. I thought I'd get this question out there first.