[Cob] Foundation for cob

[Kristen Davenport]

Hi there.
We are going to soon dig a 2-foot foundation trench for a 16-by-30 cob 
addition to our adobe house. The walls will be some parts cob and some parts 
straw bale. Our inclination is to build a foundation and stem wall out of 
mortared stone (we have plenty around here) but a local contractor guy is 
discouraging this , urging us to instead pour a concrete foundation with 
rebar, etc, etc. Meanwhile, my local "cob dude" expert urges earthbags.

Advice and stories of your experiences welcome.

Kristen