Solving the adjacency problem with stand-centred constraints

We present a new linear integer programming formulation of adjacency constraints for the area restriction model. These constraints are small in number and are a strong model for the adjacency problem. We describe constraint development, including strengthening and lifting, to improve the basic formulation. The model does not prohibit all adjacency violations, but computations show they are few in number. Using example forests ranging from 750 to more than 6000 polygons, optimization problems were solved and good solutions obtained in very short computational time.