  We present accretion rates for a large number of solar-type stars in the Cep
OB2 region, based on U band observations. Our study comprises 95 members of the
~4 Myr-old cluster Tr 37 (including 20 "transition" objects; TO), as well as
the only CTTS in the ~12 Myr-old cluster NGC 7160. The stars show different
disk morphologies, with the majority of them having evolved and flattened
disks. The typical accretion rates are about one order of magnitude lower than
in regions aged 1-2 Myr, and we find no strong correlation between disk
morphology and accretion rates. Although half of the TO are not accreting, the
median accretion rates of normal CTTS and accreting "transition" disks are
similar (~3 10^{-9} and 2 10^{-9} Msun/yr, respectively). Comparison with other
regions suggests that the TO observed at different ages do not necessarily
represent the same type of objects, which is consistent with the fact that the
different processes that can lead to reduced IR excess/inner disk clearing
(e.g., binarity, dust coagulation/settling, photoevaporation, giant planet
formation) do not operate on the same timescales. Accreting TO in Tr 37 are
probably suffering strong dust coagulation/settling. Regarding the equally
large number of non-accreting TO in the region, other processes, like
photoevaporation, the presence of stellar/substellar companions, and/or giant
planet formation may account for their "transitional" SEDs and negligible
accretion rates.
