Lacking Natural Simplicity

Recently I've decided that I want to build a house. I've been reading various books about different construction techniques, and this weekend I wandered over the family farm, once with my Dad and once with my friend H.H. looking at various possible building sites. The most picturesque sites, unfortunately, are rather remote, and would involve long, long driveways and long runs of new electric lines. There are several locations closer to electricity and the road that would be nice building spots, but some are closer to neighbors than I'd prefer, and another is someplace already in use by the farm, so there's not anything that immediately jumps to mind as perfect. I plan to spend a lot of time over the next year observing condiations at each of the better sites.

I'd like to use a many materials as I can from the family farm in the construction of the building. I'm considering building a cob house, which has a number of very attractive features, but which depends heavily on the local soil for construction material. Cob houses need a clay-sand mix. Almost all of the local soils have plenty of clay, according to the soil survey, but rather than sand the rest of the soil is mostly silt, which seems like it would be a problem for Cob. I can probably obtain sand relatively economically to add to the mix, but will the existing silt make the mix too weak? That's what I have to find out.