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The use of non-timber forest products (NTFPs) has great potential for the conservation of natural resources and rural development. Palms are important NTFPs, providing numerous products, including leaves. The harvest of palm leaves rarely results in the immediate death of individuals and can be considered one example of the sustainable use of forest resources. However, in most cases basic ecological information, such as the distribution and abundance of the species is unknown, as is information on the ecological implications of human impacts, such as leaf harvest and livestock grazing. In the tropical dry forests of northwest Mexico, leaves from the threatened palm Brahea aculeata are harvested for roofing material and represent an important NTFP. In this study, we assessed the distribution and abundance patterns of this species across 52 plots in the tropical dry forest of Sierra de Álamos-Rio Cuchujaqui Reserve in Sonora, Mexico. We also evaluated patterns of leaf harvest and cattle browse intensity on palm populations. We found that B. aculeata density is highly variable across the landscape with a mean of 121.7 ha?1. Results indicate that B. aculeata is primarily distributed near arroyos and rivers. The highest densities were found in sites with low incidence radiation and narrow stream width in arroyos/rivers (<9.5 m). Overall, fewer than 6% of the stems were seedlings. Leaf harvesting and browsing appear to affect the demographic vital rates of the species; specifically we found a significant negative effect of harvesting and browsing on smaller palms, and postive effects on growth and leaf production for larger individuals. Additionally, we found the highest germination and establishment rates were adjacent to the streams in areas which had the lowest light intensity and temperatures, and highest humidity. Results indicate the distribution, abundance of populations are influenced by several factors including seed predation/removal, micro-environmental variables, livestock grazing and leaf harvest.