  We study the scaling behavior of the quark propagator on two lattices with
similar physical volume in Landau gauge with 2+1 flavors of dynamical quarks in
order to test whether we are close to the continuum limit for these lattices.
We use configurations generated with an improved staggered (``Asqtad'') action
by the MILC collaboration. The calculations are performed on $28^3\times 96$
lattices with lattice spacing $a = 0.09$ fm and on $20^3\times 64$ lattices
with lattice spacing $a = 0.12$ fm. We calculate the quark mass function,
$M(q^2)$, and the wave-function renormalization function, $Z(q^2)$, for a
variety of bare quark masses. Comparing the behavior of these functions on the
two sets of lattices we find that both $Z(q^2)$ and $M(q^2)$ show little
sensitivity to the ultraviolet cutoff.
