Do the stumps, logs, or tree limbs turn to dirt eventually when you dig a hole and cover them? What would be the impact of doing so? I personally see no impact on the soil, I was just curious how they decompose. I have a large pile of logs and would rather dig a hole with a backhoe and bury them instead of burning the pile.
What Happens to Logs When You Dig a Hole and Cover Them?
Certified GKH Gardening Expert
They will eventually decompose, benefitting the soil, though with a large number of them as you are wanting, this will take some time--perhaps years--to fully decompose.
The logs will definitely decompose, leaving added nutrients and compost in the soil, which it does need. This provides an excellent place for earth worms, which also aids in helping the soil. Add some plants to that area, such as a bamboo, elephant ears, or even a wheat, and you not only have a composting area, but a beautiful area also.