From “Treasures of Taliesin:  Seventy Six Unbuilt Designs,” this description written by Bruce Brooks Pfeiffer, Director of the Frank Lloyd Wright Archive:

A group of auto workers, teachers, and other professionals in Detroit formed in the late thirties a cooperative organization for the purpose of buying land in the country and starting construction on a group of moderately priced houses for themselves and their families.  Eventually, they purchased a 160-acre farm to begin their venture.  At about this time, early in 1941, Taliesin apprentice Aaron Green was in the Detroit area.  He met with the cooperative in Detroit and was impressed by their idealism in trying to break out of the ordinary and establish something new.  Besides helping to build each others’ homes, they also planned to raise crops for their own consumption and for a small but welcome additional revenue.  Aaron believed that what they planned to do would fit in perfectly with Wright’s ideas about decentralization, moderate-cost housing, and leaving the overcrowded city for the country where one could live in harmony with the surrounding landscape.  Prompted by Aaron’s encouragement, some of their representatives came to Taliesin to discuss their project.

Wright was at this time interested in experimenting with rammed earth construction, and this seemed a good place to start.  As soon as the drawings for the project were under way, Aaron returned to Detroit and stayed on to help the group get started.  They purchased bulldozers, tractors, and other building equipment and drew lots to see which family’s house would be the first constructed.  Rammed earth walls were formed and a protective roof covering was begun, but the Second World War intervened.  Many of the would-be dwellers were conscripted for one cause or another, either back to Detroit for defense work or into the armed services.  Aaron himself enlisted in the air force, and while waiting to join was drafted by the army.  Trying to explain that he was already in the armed forces proved fruitless, and he was jailed until the air force came to the rescue.  With the loss of the labor force the project dwindled.  The winter snows came and the incomplete berm walls of the prototype model were washed out.  The co-op houses for Detroit thus became another war fatality.

But the project, as designed in 1942, was the pioneer of rammed earth and earth berm construction.  The walls, or earth berms, were to be treated with plaster on the inside surfaces, the earth berms outside planted with a variegated pattern of grasses and mosses.  The wide overhang would protect the outside berms.  A central section of the plan retains the berm behind stepped wall masses in order that full-length glass doors may give access to the ground level.  Windows along the tops of the earth berm walls flood the interior with light, yet are also protected by the eaves.