  The transport properties of epitaxial graphene on SiC(0001) at quantizing
magnetic fields are investigated. Devices patterned perpendicularly to SiC
terraces clearly exhibit bilayer inclusions distributed along the substrate
step edges. We show that the transport properties in the quantum Hall regime
are heavily affected by the presence of bilayer inclusions, and observe a
significant departure from the conventional quantum Hall characteristics. A
quantitative model involving enhanced inter-channel scattering mediated by the
presence of bilayer inclusions is presented that successfully explains the
observed symmetry properties.
