Supplement 1. R source code for the spatial modeling package described in this paper, including main and subroutine files, with descriptions of code and instructions for use.

File List Kernels.R<br> SpatialParams.R<br> SpatialSubs.R<br> Example.R<br> Description This supplement includes the subroutines and an example main file to be used for performing spatial simulations as described in O’Rourke and Jones (2011). It was written on a Macintosh computer running Mac OS X 10.6.7 (10J869), originally coded in R 1.8, and updated for publication to R version 2.13.0. i. Kernels.R: This is an R script containing descriptions of dispersal kernels used in our simulations. Currently included are a uniform dispersal kernel and a quereshi kernel (reference). ii. SpatialParams.R: This file contains basic parameters for the landscape including dimension, percentages of agricultural land, agricultural land devoted to corn production, and non-agricultural land; parameters for crop rotation and finally, the number of seasons (years) a given landscape will be simulated. iii. SpatialSubs.R: This file contains subroutines for creating the landscape, for insect dispersal and population growth. iv. Example.R: An example simulation. This file calls the appropriate subroutines and runs an example simulation for nyears seasons. Plots the results as a time series.