This is a bit of an experiment. I have mentioned before about my lack of compost system or worm farm, and really my 3 dogs just have a go at whatever food scraps I toss on my weed pile. Recently I chanced upon this article about worm tunnels.
The idea of incouraging more worms with no extra input from me sounds very appealing. Kath Irvine of Edible backyard, has a trench in her greenhouse that is covered in loose boards ... it seems inground worm farming is a thing.
I don't love using plastic in the garden and would love to re-create the inground bit in terracotta... if it works! If it proves to be dog proof I will look at a deeper version and a few of them.