The Ozark chinquapin (Castanea ozarkensis) is a chestnut tree whose range is concentrated in the Interior Highlands of North America. Like other North American members of Castanea, the Ozark chinquapin was reduced from an overstory tree to an understory shrub by the invasive chestnut blight fungus (Cryphonectria parasitica) during the early twentieth century. While numerous studies have documented the response of the American chestnut (C. dentata) to chestnut blight, little is known about the Ozark chinquapin's health and reproductive status post-blight. We used generalized linear models and AIC model selection to assess the factors that influence the probability of being infected by chestnut blight and to determine which variables best predict the reproductive status of the Ozark chinquapin in south-central Missouri. Models showed that Ozark chinquapin reproductive status was related to the maximum stem height of the tree and past fire frequency. The probability of blight infection was related to stem height, deer damage, and fire history. Our findings suggest that the Ozark chinquapin is capable of reproduction in certain situations but remains susceptible to chestnut blight through deer damage and the burn time interval. Thus, conservation of chinquapins could benefit from management that reduces disturbance from deer and fire mortality.

We evaluated the effectiveness of coastal dune restoration work in northern California for invertebrates with an emphasis on pollinators. Coastal dune restoration increases plant diversity by replacing just a few invasive, nonnative plants with several native plants, so we predicted that invertebrate abundance and diversity would increase in response. We employed multiple methods, including pan traps, pitfall traps, sweep netting, aerial netting, and light traps to conduct a comprehensive inventory and comparison of invertebrate community abundance, representation, and richness, evenness, and diversity at the family level. We collected significantly more invertebrates (F = 10.94, df = 1, P = 0.01) and pollinators (F = 14.25, df = 1, P < 0.01) on restored sites compared to unrestored sites in both 2018 and 2021. Similarly, we found significantly higher family richness for all invertebrates (F = 18.29, df = 1, P < 0.01) and for pollinators (F = 15.49, df = 1, P < 0.01) on restored sites compared to unrestored sites in both years. In general, we found higher family diversity and evenness indices on unrestored sites compared to restored sites for all invertebrates and only pollinators in 2018 and 2021, however only some of these differences were significant. The diversity and evenness results were driven by just a few families (especially Scarabaedae, Ephydridae, and Lauxaniidae) dominating the numbers of specimens collected on restored sites in particular. Overall, our results highlight the importance of dune restoration efforts with respect to invertebrate conservation.

A common measure of ecosystem resilience is the time course to recovery for a system that has been previously disturbed. The goal of this study was to assess whether forest lepidopteran communities displayed resilience to varying levels of timber harvest and, if so, how the time course to recovery differed among harvest regimes. Lepidoptera were sampled from 11 forest stands managed with one of three harvest treatments: no logging, shelterwood harvests, and group selection (patch cuts). Moths were sampled from all forest stands 1 y prior to harvest in 2007 and postharvest from 2009 to 2021. We use data from 2007, 2009, 2020, and 2021 to assess recovery transients across harvest levels. In the short term, moth species richness was reduced in all stand types, with the largest loss of species being in the most intensively managed stands. Recovery of species richness was varied based on harvest level. Community composition among managed and control forest stands recovered at different rates, with the most heavily logged stands requiring nearly 15 y to approach the preharvest species composition. Species that were isolated to samples in relatively few years or sampled at low abundances preharvest were seldom present within forest lepidopteran assemblages at the end of this study. Our results suggest that forest lepidopteran communities can recover from timber harvest in moderate time courses, even when the level of harvest approaches 80% of the standing bole. Persistence of the very diverse oak-feeding moth guild, however, will likely require ongoing management to sustain oak recruitment to the canopy.

Conservatism is the concept underlying Floristic Quality Assessment (FQA), a method used to reflect conservation value and ecological condition based on plant communities. The inputs to FQA metrics are coefficients of conservatism (C-values), values ranging from 0 to 10 that are assigned to individual species by experts. Conservatism is generally characterized as a species' fidelity to less-degraded remnant natural areas as determined by their sensitivity to human disturbances. However, because conservatism is sometimes broadly and dissimilarly defined in the literature, without systematic study or review, its definition has become unclear to users. We used template analyses to search for key terms in definitions of conservatism from 51 documents that described the establishment of C-values in new regions. Tolerance to “disturbance” was the most frequent term used to define conservatism, being found in over half of the documents. We then outlined the underappreciated complexities of “disturbance” when defining conservatism. Other prominent phrases included fidelity to natural areas, remnants, or specific habitats, and intolerance of human disturbance. Descriptions of species with lower C-values (0–3) often included ruderality, tolerance of heavy disturbance, and adaptation to a broad range of environmental conditions. Midrange C-values (4–6) generally related to “intermediate” conditions, dominant matrix species, and tolerance of moderate disturbance. Descriptors of advanced succession, narrow environmental tolerances, and fidelity to “high-quality conditions” were captured in higher C-values (7–10). These results reveal how researchers have variously interpreted ecological conservatism, particularly with respect to ecological concepts such as succession and specialization. We advocate for explicit, upfront, and consistent definitions of conservatism when establishing C-values in new regions and when refining existing values. When defining or using conservatism, we suggest special attention should be given to two foundational pillars of the concept: fidelity and tolerance.

Throughout the Eastern Deciduous Forest Biome, overbrowsing by white-tailed deer (Odocoileus virginianus) has reduced plant diversity and impoverished forest regeneration. However, some geomorphic features may provide refuge from browsing. For example, browse-sensitive species are often abundant on the tops of tall boulders and treefall tip-up mounds. If refugia are common, they might serve as viable seed-source populations for recovery of vulnerable plant species that have been locally or regionally extirpated. Here, we test the hypothesis that cliff edges and steep slopes provide refuge for browse-sensitive woody species. We quantified stem density or individual patch size, or both, of four woody species at six steep exposures across the Hemlock-Northern Hardwoods Association. Level areas adjacent to steep exposures served as deer-accessible reference sites. The combined density of our focal species was 16 times higher on cliff edges and steep slopes versus reference areas, and combined mean patch size was nearly six times larger. We also conducted a remotely sensed spatial analysis of slopes between 35° and 75° throughout the State of Pennsylvania to quantify the abundance and spatial aggregation of these potential refugia. Steep slopes occurred in all 67 Pennsylvania counties, representing up to 3% of land surface in rugged counties. Steep slopes were also often clustered or large, suggesting locally high gene flow may maintain genetically diverse and vigorous seed-source populations of browse-sensitive species. Our study is the first to quantitatively demonstrate that cliff edges and steep slopes have high conservation value by serving as browsing refugia for browse-sensitive woody plants in temperate forests.

Temperate savannas and grasslands maintained by frequent, low-intensity fires are among the most species-rich plant communities in the world. One untested mechanism by which frequent fires increase plant species diversity is increased survival of fire-dependent species. I examined how the frequency of simulated fire (clipping combined with litter removal) affected the survival of nine fire-dependent, perennial groundcover plant species over two growing seasons at each of two pine savannas in southeastern Mississippi (USA). I established two experiments. Experiment 1 examined transplant survival from May 2017 to October 2018 of five moderately common species in plots treated annually from 2014 to 2017 and in adjacent untreated plots. The five species were Bigelowia nudata, Rhynchospora latifolia, Carphephorus pseudoliatris, Eriocaulon compressum, and Triantha racemosa. Experiment 2 examined the effect of reducing treatment frequency in 2018 in Experiment 1 plots on survival from May 2022 to October 2023 of naturally occurring individuals of the four most fire-responsive species (Drosera capillaris, Dichanthelium ensifolium, Pseudolycopodiella caroliniana, and Rhynchospora oligantha). Survival of transplants varied significantly among species but was not greater in frequently treated plots than in untreated plots. Reducing treatment frequency did not cause a significant decline in post-treatment survival of any of the four species monitored in situ. Results do not support the hypothesis that frequent fires increase 2 y survival of established individuals of fire-dependent species. Results are consistent with a hypothesis that frequent reductions of standing dead and litter by fire maintain species diversity by instead improving conditions for recruitment of fire-responsive species.

Conservation of rare species often relies on the delineation of management units and genomic tools can now be applied for this purpose. However, this is not as common on a local scale, where populations are often small and fragmented, despite the utility of informing conservation and management practice at the regional level. We use a genotyping by sequencing (GBS) approach to assess the perennial riparian plant species Baptisia australis (Fabaceae) in Pennsylvania, where the taxon is at the edge of its natural distribution and considered threatened. In this system, we investigate whether sampled subpopulations exhibit genetic structure. We find that genetic structure largely aligns with the waterways that were sampled, with five genetic clusters, one for each of three waterways and two additional clusters along a fourth waterway. This work directly addresses conservation priorities in the state and informs delineation of management units that will be used in conservation practices.