  Near infrared spectra of 133 red giant stars from ten Galactic open clusters
and two Galactic globular clusters spanning 2.2 dex in metallicity and 11 Gyr
in age are presented. We combine this sample with ten clusters from Cole and
collaborators to investigate the Ca II triplet line strengths and their
relation to cluster metallicity and position along the red giant branch. We
show that characterizing the stellar surface gravity using Ks band photometry
(relative to the horizontal branch) taken from the Two Micron All-Sky Survey
allows for metallicity measurements at least as precise as those derived using
V or I band data. This has the great advantage that uniform photometry and
reliable astrometry is available for a large number of clusters. Using Ks band
photometry also reduces the effect of differential reddening within a given
cluster. We find no significant evidence for age or metallicity effects to the
linear Ca II triplet - metallicity relationship over the small range in
magnitudes studied when homogeneous reference metallicities are used. We derive
the first spectroscopic metallicity and new radial velocity estimates for five
open clusters: Berkeley 81, Berkeley 99, IC 1311, King 2, and NGC 7044. King 2
has an anomalous radial velocity compared with the local disk population. We
discuss the possibility that it is part of the Monoceros tidal stream.
