Harvesting of two alpine Artemisia : Effects of an amateur practice on wild plant dynamics

Societal Impact Statement Wild plants are consumed all over the world, and knowledge of the effects of harvesting is necessary to ensure the sustainability of this activity. Our 3‐year study of two closely related alpine Artemisia species in the Southern Alps revealed a positive impact of harvesting at the plant scale and on the short term. The response of plants to harvesting interacts with ecological conditions of the site and differs between the two species. A long‐term understanding of plant dynamics at the plant and population scales is now required to fully assess the impact of harvesting practices and propose adapted conservation measures. Summary Characterizing the dynamics of wild harvested plants is essential to assess the sustainability of such practices. In extreme environments offered by high mountains, both ecological (e.g., vegetation cover and climate) and sociological (e.g., frequentation and harvesting practices) conditions show marked variation in space and time. Little is known however about how variation in harvesting and ecological conditions affects the dynamics of high‐mountain plants, due to practical difficulties of monitoring (e.g., low accessibility) and the need to conduct multisite studies. Here, we assess the effect of variation in social‐ecological conditions on the dynamics of two alpine Artemisia species, whose stems are harvested to flavour tea, wine or liqueur. We monitored plants of Artemisia glacialis and Artemisia umbelliformis in 39 sites of the Southern Alps during three consecutive years (2021–2023). Mortality is low in the 3 years of study. Harvesting has a positive effect on plant stem production from year to year for both species, but for A. glacialis , both the effects of harvesting and the transition from vegetative to flowering status are mediated by variation in ecological conditions. The effect of harvesting on plant dynamics at the plant scale and on the short‐term is positive. Further studies are needed to assess whether this result is repeated at the population scale and for long‐term dynamics. Variation between the two closely related species illustrates that it is not possible to conclude on the sustainability of harvesting for one species based on the dynamics of a closely related species.