Maybe there was still some heat being generated by the UCG themselves. I sifted 10 gal of espresso grounds from Starbucks into a plastic tote in the fall and after a week they started to heat up all on their own. They got up to 110F for quite a while even in such a small pile with ambient temps around 50F!

Harry

Your comment got me curious, so today I went out with my infrared (laser) thermometer gun.The ambient air was 33F, the outside of the pile was at 32F.

When I moved a bag under it I could see a pile of worms moving, not fast but wiggling. The gun said the temp was 32F.

I am surprised to say the least. I dug down with a trowel (no deeper than the towel blade) to add things to the center and revealed a 36F temp and more worms.

Don't know if they go into some kind of suspended antimation when it gets colder but that is what I found today 2016Jan15.

This is very interesting that worms would be active at those temps in a cold compost pile. I also get starbucks grounds when I can and mix them in the compost pile to heat up the piles. My pile is decently large at 3' x 4' currently and by adding grounds in layers and trying to keep the grounds centerized my pile is heating up from 40 degrees slowly since the last turn 3 days ago to the current temp of 140 F. Of course if your pile is hot or heating up any worms in the pile they will leave until it cools again. I do keep my pile covered because it has been unusually warm with a lot of rain here in the mid-west. As long as the inner pile continues to heat I wont turn again until it maxes out. Previously this same pile had heated to about 150F.

I was surprised also which is why I posted. I am more of a lazy composter meaning I don't turn or mix my compost to heat it up. I have on occasion used a fork to lift sections to allow air into the pile.

This time of year I am normally out traveling and don't mess with things outside even when home.

The bin is a 3ft cube made of a Trex type material. I got it from a friend some years back who got it from his town so not sure of the origin. He could never get the compost thingy working (like most people) so it sat in his yard until one day he said he wanted it out of there.

I put it way out back and used it for quite a few years but had troubles keeping rodents out of it. So a couple years ago I decided to bring it near a garden bed but also reinforced it using 1/4" hardware cloth (inside) on all sides, top, & bottom because I wanted to put in kitchen scraps but wanted to keep the rodents out. Made a sliding top covered with an old shower curtain to keep the rain out and it has worked great ever since.

I don't actively compost in the winter which is why I started using worms indoors. I just put the kitchen scraps outside in a trash can and use those to started off in the spring.

It was like a spring day today so I went back out today to check again. Ambient air @50F. When I moved the plastic coffee bags the worms were re-active to the light. The laser gun said it was 42F under the bag and right on a worm. I collected a few more and some were active enuff to climb out of the container.

The worms must go into some kind of suspended lethargic state until it warms up again? That is unless it goes into s deep freeze? It's all news to me.