Not really sure if any one would be better than others.Art- can you recommend the best type of wood for the ramial wood chips to use for the run?
A mix of hard and soft woods would be fine.
No poison ivy/oak.... and/or lunch materials would be good.

(Had a bunch of non-organic stuff in one load.)
Best to let it age a bit before piling it into the run to avoid toxic mold blooms.