Just got back home guys.  Integracer02, I agree.  The old survey (if a complete survey was ever done) appears to be lacking in specifics i.e., species, distribution, tree size, and tree density.  In all likelihood, prior estimates looked only at surrounding forest and projected a conservative estimate of what might be present in this concession area.  I presume North Cal may have been involved in determining specific tree species present, but really can't comment further, since no mention of North Cal was provided.