Overwintering on balcony

[NEBeech]

What about a heat bed?

One of the original threads

Heat bed meduim? Pumice or bark " sawdust"

Was curious if anyone could clarify. @Ira I know Ryan uses and talks about pumice as the heat conductive material at the bottom of heat beds ( depth being the key variable). But when Ryan and Randy discuss about post collection Yamadori recovery Randy explains that for a single year and for trees that require rapid root growth, he has seen bark " sawdust" give superior results. Why would you not utilize this at the bottom of a heat/recovery bed? Is the nuance dependant on the trees roots bein…