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Woodpeckers were surveyed at each point using a silent listening period of 6 minutes, followed by a 6 minute playback period for American three-toed woodpecker, and a 6 minute playback period for Pileated woodpecker. All woodpeckers seen or heard during all 3 periods were recorded. This study was designed specifically for American three-toed and Pileated woodpeckers. If the target species was detected during its corresponding survey period, that portion of the survey was ended. As a result, the level of effort, as measured by time spent surveying for woodpeckers at a given point, was not the same at each point. Additionally, 16 of the 44 grids were visited twice in order to assess the effects of time on detection probability, resulting in roughly double the effort. Sites selected for surveys were chosen using a spatially balanced survey design that selects sites randomly but enforces spatial balance across the study area. It also allows for stratification of effort, we placed 70% of our samples in managed forest landscapes with some history of timber harvest and 30% in forests that did not a history of timber harvest.