  We investigate the influence of environment on brightest cluster galaxy (BCG)
evolution using a sample of 63 clusters at 0.3 < z < 0.9 drawn primarily from
the Las Campanas Distant Cluster Survey and follow-up V, I, and K' photometry.
The luminosity evolution of the entire BCG sample is not adequately described
by a single evolutionary model. Using the integrated light from the cluster
detection as a proxy for cluster Lx and the suggestion by Burke, Collins, &
Mann, we set Lx = 2 x 10^{44} ergs/s to be the division between high and low
luminosity clusters. At high redshift (z>0.6) BCGs from low-Lx clusters are
fainter, on average, than those from high-Lx clusters and are best modeled as
having constant luminosity with redshift. The BCGs from high-Lx cluster are
best modeled as having a stellar population that formed at large redshift
(z_form > 5) and is passively evolving. However, for the entire BCG population,
the observed V-I and I-K' colors are well described by a single evolutionary
model in which the stellar populations have z_form > 5 and subsequently
passively evolve. We conclude that accretion is proportionally more significant
for BCGs in lower mass clusters at these redshifts (factor of 2 to 4 increase
in mass since z ~ 1 for the low Lx systems) and that the accreted matter is in
the form of systems with evolved stellar populations.
