More often then not a bare ground in a crawl space will produce vapour. In our west coast climate it is a given. Mould, mildew or fungi develop very quickly and can turn to a very unhealthy environment.
I always strongly urge that the bare earth be properly sloped, covered fully with a vapour barrier, be properly vented (ambient or mechanically) and inspected every season.

T.Neyedli
www.alphahomeinspections.ca