  The long-wavelength physics of monolayer graphene in the presence of periodic
strain fields has a natural chiral scattering network description. When the
strain field varies slowly compared to the graphene lattice and the effective
magnetic length of the induced valley pseudomagnetic field, the low-energy
physics can be understood in terms of valley-polarized percolating domain-wall
modes. Inspired by a recent experiment, we consider a strain field with
threefold rotation and mirror symmetries but without twofold rotation symmetry,
resulting in a system with the connectivity of the oriented kagome network.
Scattering processes in this network are captured by a symmetry-constrained
phenomenological $S$ matrix. We analyze the phase diagram of the kagome
network, and show that the bulk physics of the strained graphene can be
qualitatively captured by the network when we account for a percolation
transition at charge neutrality. We also discuss the limitations of this
approach to properly account for boundary physics.
