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Virginia spiraea (Spiraea virginiana Britton, Rosaceae) is a putative shade-intolerant, disturbance-adapted, riparian shrub species native to the southern Appalachian Mountains. This species was listed as threatened in 1990, and a federal recovery plan was developed in 1992. Current reassessment of the recovery plan includes proposals for propagation and out-planting to supplement and restore wild populations. Genotypes with greater shade acclimation would likely have higher survival in natural populations, would require less frequent shade-reduction management, and could be integrated into populations that need restoration. In summer 2022, we examined steady-state (maximum light-saturated photosynthetic, dark respiration rates, quantum yield, light compensation point) and dynamic (photosynthetic induction and loss patterns) photosynthetic characteristics, pigment concentrations, and specific leaf mass of cloned propagules from five elements of occurrence along the South Fork of the New River in Ashe County, North Carolina, along an artificial light gradient (100%, 75%, 50%, and 20% of full sun) in a common garden. Data were compared among light treatments using ANOVA or non-parametric tests. Light treatment had significant effects on maximum photosynthesis, dark respiration, specific leaf mass, and light compensation, but not quantum yield, pigment concentrations, or induction and loss times. Some parameters had plasticity similar to that seen in other woody shrubs, while others were less plastic. A surprising finding was that plants performed better under 75% full sunlight suggesting an ability to tolerate, and maybe even a preference for, partial shade in this species. Future studies should examine photosynthetic characteristics of individuals from genetically contrasting source populations. [ABSTRACT FROM AUTHOR]

In response to the American Association for the Advancement of Science's Vision and Change in Undergraduate Biology Education initiative, we infused authentic, plant-based research into majors' courses at a public liberal arts university. Faculty members designed a financially sustainable pedagogical approach, utilizing vertically integrated curricular modules based on undergraduate researchers' field and laboratory projects. Our goals were to 1) teach botanical concepts, from cells to ecosystems; 2) strengthen competencies in statistical analysis and scientific writing; 3) pique plant science interest; and 4) allow all undergraduates to contribute to genuine research. Our series of inquiry-centered exercises mitigated potential faculty barriers to adopting research-rich curricula, facilitating teaching/research balance by gathering publishable scholarly data during laboratory class periods. Student competencies were assessed with pre- and postcourse quizzes and rubric-graded papers, and attitudes were evaluated with pre- and postcourse surveys. Our revised curriculum increased students' knowledge and awareness of plant science topics, improved scientific writing, enhanced statistical knowledge, and boosted interest in conducting research. More than 300 classroom students have participated in our program, and data generated from these modules' assessment allowed faculty and students to present 28 contributed talks or posters and publish three papers in 4 yr. Future steps include analyzing the effects of repeated module exposure on student learning and creating a regional consortium to increase our project's pedagogical impact.

American ginseng (Panax quinquefolius) roots have long been harvested for use in herbal medicine. Overharvesting has threatened long-term viability of wild American ginseng populations. Research has been ongoing to determine factors affecting the variation of ginsenosides in roots. Given the conservation concerns regarding wild American ginseng, we began experimenting with a partial-root harvest method in 2014 for extracting tissue for ginsenoside analysis without killing individual plants or causing long-term declines in wild populations. We took partial-root harvest samples from 57 plants in four wild populations throughout western North Carolina and monitored morphological attributes of these and 56 paired, unharvested plants of similar size for four years after harvest. Partial-root samples were taken from an additional 162 plants from 16 new populations in 2015 and 2016. Morphological attributes of these plants were monitored annually or biannually. In the paired plant study, annual reemergence did not differ between harvested and unharvested plants in any year after harvest. Leaf area was significantly lower in harvested plants than unharvested controls in the first year postharvest, but these differences did not persist after the first year. In the unpaired study, preharvest-postharvest comparisons were more variable, likely due to different harvest years and interannual variation in weather. Our results demonstrate that partial-root harvest could be an effective way for ginsenoside researchers to reduce their impact on wild and cultivated American ginseng populations and it may represent a non-destructive harvest protocol for root tissue phytochemical analysis. [ABSTRACT FROM AUTHOR]

We studied the habitat characteristics of Spiraea virginiana Britton (Virginia spiraea), a federally threatened riparian shrub, along eight rivers in western North Carolina. Comparisons between plots with and without S. virginiana revealed that S. virginiana plots were on steep, south-facing slopes and had a higher percentage of large substrate, lower herbaceous and vine cover, higher non- S. virginiana shrub density, lower tree influence, and higher visible sky than control plots. When relating these habitat attributes to the presence/absence of S. virginiana using conditional logistic regression, only substrate size and non- S. virginiana shrub density had significant effects on S. virginiana presence. Principal components analysis (PCA) of all plots ( S. virginiana and control) found S. virginiana plots separating from controls that had higher vine and herb cover and lower non- S. virginiana shrub density and slope. Spiraea virginiana plots at the Cheoah River separated from other sites by having greater substrate size and tree influence, and lower visible sky and herb cover. Regression analysis between S. virginiana volume and PCA axes (of plots with S. virginiana only) indicated that volume increased with increasing small substrate, visible sky and non- S. virginiana shrub density, but decreased with increasing tree influence, herb and vine cover, and decreasing slope. Spiraea virginiana restoration efforts should focus on habitats with the attributes described in this study to favor its presence. To ensure S. virginiana vigor, competition from trees, non- S. virginiana shrubs, vines and herbs, especially aggressive nonnative species, should be reduced. [ABSTRACT FROM AUTHOR]