Christmas-related moss harvesting promotes the recruitment of the endangered conifer Abies hickelii

Abstract

The harvesting of mosses for ornamental purposes is a common activity worldwide. In some parts of Latin America and Europe, this activity is directly linked to the Catholic tradition of making nativity scenes at Christmas. At the end of each year, rural communities extract the moss layer from temperate forests and sell it in regional markets. The ecological impacts of this activity on temperate ecosystems and the vascular plants that inhabit them are poorly documented in the literature. Here, we determine the effects of moss layer harvest on the recruitment of the endangered species Abies hickelii in eastern Mexico. To this end, we conducted a series of in situ studies to determine the effects of moss layer harvest on (i) seeds and established seedlings, (ii) seedling emergence and (iii) seedling establishment of this conifer. We found that moss layer removal had positive and neutral effects on the early life stages of A. hickelii. Moss harvesting had minimal impact on the total seed input from the 2017–2018 mast event, as it occurred weeks before the peak of A. hickelii seed dispersal. After two years, the absence of the moss layer was associated with a higher number of emerged and established seedlings. We discuss the ecological implications of our findings and make recommendations for Christmas-related moss harvesting and future A. hickelii conservation efforts. Finally, although we found no significant negative effects of moss harvesting on A. hickelii, we only studied this one species, and the effects of this activity on other species are still unknown, so we recommend a cautious approach to moss harvesting.