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A surprisingly large number of species potentially threatened by human harvest lack quantitative ecological studies incorporating harvest effects, especially clonal species in the alpine Himalayas. We studied density and biomass variation of a threatened medicinal herb, Neopicrorhiza scrophulariiflora, to examine the effect of harvest on plant performance. The study covered two regions with contrasting harvest situations—one with open‐access and another protected from commercial harvesting. Four populations from each region were compared along an elevation gradient (3,800–4,800 m). Also, we conducted in situ interviews with 165 and 38 medicinal and aromatic plant users in open‐access and protected regions, respectively, to assess the collection and use patterns of the target species. The quantity harvested per household for traditional healthcare use was similar in both regions. We found no evidence of trade‐driven collection in the protected region but in the open‐access region a trade‐based annual collection of 35–465 kg dried rhizomes per household had a strong negative effect on both density and biomass. In the protected region, the effect of harvest intensity on plant density was positive for vegetative and negative for reproductive individuals, whereas in the open‐access region, the effect was negative for both vegetative and reproductive individuals. The results indicated that a low harvest intensity had no adverse impact on N. scrophulariiflora populations; however, quantification of the optimum level of harvest remains to be explored. Shrub vegetation appeared to buffer the harvest impact on plant density, possibly through the retention of additional moisture. To maintain population viability, we suggest regulating harvest, for example, by introducing rotational harvest systems, ensuring that a sufficient number of reproductive individuals are left as a source of propagules in each harvested population and that populations are given time to recover between harvests. A surprisingly large number of species potentially threatened by human harvest lack quantitative ecological studies incorporating harvest effects, especially clonal species in the alpine Himalayas. We studied density and biomass variation of a threatened medicinal herb, Neopicrorhiza scrophulariiflora, to examine the effect of harvest on plant performance. The study covered two regions with contrasting harvest situations—one with open‐access and another protected from commercial harvesting. Four populations from each region were compared along an elevation gradient (3,800–4,800 m). Also, we conducted in situ interviews with 165 and 38 medicinal and aromatic plant users in open‐access and protected regions, respectively, to assess the collection and use patterns of the target species. The quantity harvested per household for traditional healthcare use was similar in both regions. We found no evidence of trade‐driven collection in the protected region but in the open‐access region a trade‐based annual collection of 35–465 kg dried rhizomes per household had a strong negative effect on both density and biomass. In the protected region, the effect of harvest intensity on plant density was positive for vegetative and negative for reproductive individuals, whereas in the open‐access region, the effect was negative for both vegetative and reproductive individuals. The results indicated that a low harvest intensity had no adverse impact on N. scrophulariiflora populations; however, quantification of the optimum level of harvest remains to be explored. Shrub vegetation appeared to buffer the harvest impact on plant density, possibly through the retention of additional moisture. To maintain population viability, we suggest regulating harvest, for example, by introducing rotational harvest systems, ensuring that a sufficient number of reproductive individuals are left as a source of propagules in each harvested population and that populations are given time to recover between harvests.

Despite the widespread use and trade of the highly valued Himalayan medicinal plant, Neopicrorhiza scrophulariiflora, there is still inadequate information on its distribution and on the environmental factors that define suitable habitats. Such information is needed to identify suitable areas for sustainable resource extraction. We hypothesize that there is a discrepancy between the geographical distribution of trade and climatically suitable areas and suggest that this could lead to a risk of local depletion of the species, which could seriously affect rural livelihoods. To address this hypothesis, we conducted species distribution modeling of N. scrophulariiflora using Maximum Entropy with ten environmental variables and 63 species occurrence records (after rarefaction) from Nepal and related the resulting distribution model to trade assessment statistics from 12 fiscal years (2004–2016). The predicted area of suitable habitat in Nepal was estimated at 11,617 km2, and highly suitable areas were located in a narrow elevational range (4000–4400 m), with a predicted area of 386 km2 (0.3 %). Suitable and highly suitable areas were mostly located in the eastern mountains, probably due to mild temperatures and adequate precipitation around the peak of the plants’ growing season. Available official trade records indicated that Nepal exported only 372 tons of N. scrophulariiflora rhizomes in 2004–2016 (average: 31 tons/annum), mostly from the western mountains where predicted habitats were classified as less suitable. Discordant geographical patterns of habitat suitability, extraction from habitats of low suitability, and increasing trade indicate that the current resource exploitation is likely to be unsustainable. We suggest formulating management strategies for locations with heavy collection and trade, conducting cultivation trials in suitable patches, and identifying sustainable annual harvest limits.