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Ecosystem services (ES) span the interface of social and ecological systems, which makes them inherently challenging to measure. Tracking ES patterns over long time frames is crucial for understanding slow variables and complex interactions, but long-term studies of ES are rare. Historical records can play an important role in revealing temporal patterns of ES, but because they rarely measure ES directly, historical ES reconstruction presents new practical challenges. Furthermore, long-term data are limited in availability, quality, and structure. We review the utility, strengths, and challenges of some unconventional historical data sets with the potential for long-term ES tracking (e.g., aerial photography, oral history, tree rings.). We link each type of data to a simple ES framework that distinguishes ES capacity, ES flows, and ES demand. Using multiple historical data sets in parallel may enhance our understanding of ES sustainability and ES interactions.