Tropical high altitude ecosystems are particularly vulnerable to the combined effects of land degradation and climate change. Mountain ecosystems globally have been extensively altered through deforestation, burning, and grazing of livestock. We are testing how native grasslands respond to reduced grazing pressure and how these responses vary across an altitudinal gradient. We have established a series of small grazing exclosures in the Cordillera Blanca in Huascaran National Park and are monitoring how plant communities and soil physical and chemical properties respond to the presence and absence of grazing pressure. We are combining these results with rapid assessments of grassland condition and remote sensing techniques to assess changes in vegetation cover over time.