Re: How were these constructed?
Heh, truly. I did it around christmas last winter. To pass time during the holidays...
I'm not sure how many hours it took, but ten could be a good estimate. I tried some new approaches, most importantly I did the surface coating with ground bark mixed in with grout.
I also tried a new way of strengthening the outcome by laying in some thin rope, dipped in grout and then put onto the roots. It seems to work really good.
There is also a network of metal wire in the foam...
A lot of fun, yes. A way to stay sane, actually. Well, sorta.