We use wax to seal mushroom sawdust and dowel spawn into logs. This prevents pests and dehydration destroying your spawn. The food grade wax is the wax used to coat Edam cheese, it is very pliable and does not chip off the logs when cold in winter. We find soy wax less flexible but it is not petroleum based. We would prefer to use beeswax, however the bees seem to steal it back !
We don’t seal the ends of our logs, only the stumps of branches and inoculation holes.
All types of wax will catch fire if over-heated.