  The differential cross section, $d\sigma/dt$, for $\rho^0$ meson
photoproduction on the proton above the resonance region ($2.6<W<2.9$ GeV) was
measured up to a momentum transfer $-t = 5$ GeV$^2$ using the CLAS detector at
the Thomas Jefferson National Accelerator Facility. The $\rho^0$ channel was
extracted from the measured two charged-pion cross section by fitting the
$\pi^+\pi^-$ and $p\pi^+$ invariant masses. The low momentum transfer region
shows the typical diffractive pattern expected from Reggeon-exchange. The
flatter behavior at large -t cannot be explained solely in terms of
QCD-inspired two-gluon exchange models. The data indicate that other processes,
like quark interchange, are important to fully describe $\rho$ photoproduction.
