  Given a fibered link, consider the characteristic polynomial of the monodromy
restricted to first homology. This generalizes the notion of the Alexander
polynomial of a knot. We define a construction, called iterated plumbing, to
create a sequence of fibered links from a given one. The resulting sequence of
characteristic polynomials has the same form as those arising in work of Salem
and Boyd in their study of distributions of Salem and P-V numbers. From this we
deduce information about the asymptotic behavior of the large roots of the
generalized Alexander polynomials, and define a new poset structure for Salem
fibered links.
