Sorry I lost Ed heite's message on building techniques by reading it on line.
 
Earthfast construction was certainly known in England in the C17 but appears
to have been rare by this date and reserved for outbuildings as at Norton
Village in Cheshire excavated in the 1970s by Patrick Greene and Peter Hough
and published in the Cheshire county journal- sorry I haven't the reference to
hand but see _Post-med Arch_ 9 (1975), 252-3. The settlers were thus surely
well aware they were choosing an temporary method of construction for what
ever reason and were not just planting the normal house construction they knew
at home. They may not have been aware of termites but post rottting can happen
pretty rapidly in Britain's miserably wet climate- any jobs going in Florida?.
However, they continued to _choose_ impermanent methods in Virginia long after
they experienced termites as brilliantly analysed by Carson, G., Barka, N.F.
Kelso, W.M.  Stone, G.W. and Upton, D. 1982, 'Impermanentarchitecture in the
southern American colonies', in _Winterthur Portfolio_ 16 (2/3), 135-96.
paul courtney, Leicester, UK