  In the discussion of hadronization at or close to the freeze-out curve
statistical (hadron resonance gas) models play an important role. In
particular, in the charmonium sector, regeneration models are considered which
rely on the fact that charmonium states can form again already at temperatures
well above the QCD transition or hadronization temperature. An important
ingredient in these considerations is the regeneration or hadronization of open
charm states. In this talk we report on a lattice QCD analysis of correlations
of open strange and charm with other conserved quantum numbers like the net
baryon number and electric charge. We analyze the temperature range in which an
uncorrelated hadron resonance gas (HRG) provides an adequate description of
such correlations. This limits the range of validity of HRG based
thermodynamics in open flavor channels and provides an estimate for the melting
temperature of heavy-light hadrons.
