Rare Plant Populations Research Articles

Enhancing rare plant population predictions through demographic modeling of seed predation, dispersal, and habitat suitability

Enhancing rare plant population predictions through demographic modeling of seed predation, dispersal, and habitat suitability

Assessing plant translocation success: common metrics mask high levels of inbreeding in a recently established Banksia brownii (Proteaceae) population

Context As threatening processes continue to impact rare plant populations, the use of translocations is becoming increasingly frequent. The ultimate success of translocation, attaining long-term persistence, is determined by species’ ability to reproduce, recruit, and maintain levels of genetic diversity that permits the capacity to adapt to environmental change. Aims This study aimed to assess translocation success of Banksia brownii. Methods We compared genetic diversity, reproductive output and aspects of the mating system of a translocated population with four reference wild populations. Key results We found that the use of multiple source populations for the translocation resulted in levels of genetic diversity comparable to reference populations of high diversity. Reproductive output was highest in the translocated population and a positive relationship between plant size and number of flowers across all populations was evident. However, mating system analysis revealed a large difference in outcrossing rates between populations in different habitats despite common pollinators, with the translocated population having the highest rates of selfing. Conclusion Whilst genetic diversity and reproductive output were comparable or higher in the translocated population than in the reference populations, assessing translocation outcomes by these measures alone can potentially mask the longer-term erosion of genetic diversity through unfavourable patterns of mating. Implications We recommend using multiple metrics of reproductive, recruitment and genetic diversity to properly assess plant translocation success.

Why Partner with a Zoo or Garden? Selected Lessons from Seventy Years of Regional Conservation Partnerships at the Arizona-Sonora Desert Museum

Zoos and botanical gardens (ZBGs) play a variety of roles in regional conservation partnerships, including their most common role as the ex situ managers of rare plant and animal populations. Using case studies from a 70-year history of conservation work at the Arizona-Sonora Desert Museum in Tucson, Arizona, USA, this paper illustrates these roles and the characteristics of ZBGs that make them versatile and effective regional conservation partners. ZBGs commonly play the role of conservation advocates, as discussed in the context of the establishment of protected islands in the Gulf of California. ZBGs also conduct field research, including the collection of long-term datasets, as exemplified by the establishment of the Ironwood Forest National Monument and a 40-year Sonoran Desert phenology database. ZBGs can be effective conveners of communities and conservation partners in regional-scale efforts, such as the Sonoran Desert Conservation Plan and Cooperative Weed Management Areas. The paper also explores the challenges faced by ZBGs in sustaining their conservation work.

Prescribed burning has limited effects on the population dynamics of rare plants

AbstractRare species serve important ecosystem functions, including community resilience to global change. Yet rare species are disappearing globally because of anthropogenic activities such as fire suppression. Prescribed burning is a widespread management approach that can reduce invasive plant presence, recycle nutrients, and restore species diversity. However, the effects of prescribed burning on rare plants are not well understood. We analyzed the population dynamics of 67 rare, native plant species in response to prescribed burning using the Chicago botanic garden's Plants of Concern dataset. This dataset includes rare plant populations concentrated in the northeast part of Illinois, and a few populations in Indiana and Wisconsin, United States. We evaluated the effects of burning by comparing the percent change in population size in the short‐term (1–2 years) and long‐term (3–4 years) after prescribed burning, to the percent change in population size not following burns. In a global model with all species, we did not detect the effects of burning on percent change in population size. In species‐level analyses, we detected burn effects for most species for which we had the statistical power to detect possible burn responses, although the direction of their responses was mixed. Five species responded consistently between short‐ and long‐term datasets, and four species had mixed responses, with most responding positively over the short‐term and negatively over the long‐term. We complemented this analysis with a literature review of fire responses for available species. Our literature review revealed more responses to burning than what we found from our analyses; however, most of this evidence does not compare burned and unburned populations directly and should be treated cautiously. Through community science monitoring efforts, we were able to compile one of the largest studies of burn effects on rare plants to date, but continued monitoring is necessary to fully evaluate how prescribed burning impacts rare plant species.

Ecological and typological assessment of forest vegetation in Starogutskyi forest — National Nature Park (NNP)

Preservation of the biodiversity of forest phytocenoses is one of the urgent tasks in the field of environmental protection. The formation of sustainable plantings with the possibility of reproduction of natural ecotopes, preservation and protection of rare plant populations is the main task of environmental protection organizations, including the Desnyansko-Starogutsky NТP. The ecological and typological assessment of the territory of the forest massif of the park allows to optimize efforts to create conditions for increasing its phytodiversity. The analysis of natural and artificially created forests on the territory of the Starogut part of the National Nature Park “Desnyansko-Starogutsky” showed the distribution of tree species depending on the characteristics of the ecological conditions of their growth. According to the forest ordering, the total area covered by forest vegetation is 6778,8 ha. Allocation of forest section areas by edatopes is the following: trophotopes — pinewoods (1,8 ha, 0,02%), subors (4510,1 ha, 66,53%), sudubrava (2266,9 ha, 33,44%), oak forests are not available; hygrotopes — dry conditions (0,7 ha, 0,01%), fresh (3948,2 ha, 58,24%), damp (2151,1 ha, 31,73%), humid (605,4 ha, 8,93%), wet (73,4 ha, 1,08%), very dry — not available. The number of types of woods covered by forest vegetation equal ten. Fresh oak and pine subor (2594,5 ha, 38,27%) prevail, humid oak and pine subor (1430,5 ha, 21,10%), and fresh oak and pine sudubrava (1352,6 ha, 19,95%) occupy slightly smaller areas. The main forest species is Pinus sylvestris (5092,7 ha, 75,13%). Smaller areas are occupied by Betula pendula (1207,1 ha, 17,8%), Alnus glutinosa (201,4 ha, 2,97%), Piceaabies (111,5 ha, 1,64%), Quercus robur (90,0 ha, 1,33%), the others are presented in small numbers. Allocation of forest sections by edatopes in the protected area is the following: reserved area — fresh and humid subors (1181,1 ha, 55,47%) and sudubrava (849,4 ha, 37%) prevail, area of regulated recreation — fresh and humid subors (2336,4 ha, 59,89%) and sudubrava (1164,2 ha, 29,84%), an economic area also has fresh and humid subors (430,7 ha, 73,85%) and sudubrava (137,5 ha, 23,58%).

Current State of Coenopopulations of Some Rare Endemic Species in Navoi Region, Uzbekistan

Abstract The problem of preserving the biological diversity of the Earth is attracting increasing attention of the world scientific community. Rare plant species, as the most vulnerable part of the flora, are under the greatest threat of extinction. In the study of this group of plants, population methods are increasingly being used. Revealing the number, structure, efficiency of self-renewal and resistance of populations of rare plants in relation to anthropogenic influences creates the basis for developing effective measures for their protection. The aim of the study was to assess the current state of coenopopulations of some rare endemic species – Acantholimon nuratavicum Zakirov ex Lincz. (Plumbaginaceae), Cousinia pseudolanata Popov ex Tscherneva (Asteraceae), Lepidolopha nuratavica Krasch. (Asteraceae) included in the Red Book of Uzbekistan. The results showed that in the ecological–coenotic conditions of the Navoi region, the studied coenopopulations are normal and incomplete. Ontogenetic spectra of coenopopulations are centred and left sided, with a peak for middle-aged and young generative individuals, which is associated with the ecological conditions of habitation and anthropogenic pressure.

RNA-Seq reveals adaptive genetic potential of the rare Torrey pine (Pinus torreyana) in the face of Ips bark beetle outbreaks

The ability of tree species to adapt to water stress and increased frequency of bark beetle outbreaks with climate change may increase with population size and standing genetic variation, calling into question the resilience of small, rare plant populations. The Torrey pine (Pinus torreyana) is a rare, genetically depauperate conifer that occurs naturally in a mainland and island population in southern California. Due to recent declines in the mainland population coinciding with drought and Ips paraconfusus bark beetle outbreaks, the species would benefit from an assessment of adaptive genetic diversity. Here, we use RNA-Seq to survey gene-coding diversity across 40 individuals to (1) characterize patterns of genetic diversity in the species and (2) test for genetic differentiation between trees that succumbed to beetle attack or survived following an outbreak. Consistent with previous studies, we found few genetic variants, with most SNPs occurring as fixed differences between populations. However, we found structure within the mainland and polymorphisms segregating in both populations. Interestingly, we found differentiation in genotypes between attacked and surviving trees and 11 SNPs associated with survival status, several of which had defense-related functions. While low diversity suggests limited adaptive capacity, genetic associations with survival in functionally relevant genes suggest adaptive potential for bark beetle defense. This initial study prompts future research to explore the genetic basis of putative resistance and suggests conservation efforts should protect surviving genotypes and the full spectrum of genetic diversity across populations to preserve the evolutionary potential of the species.

Adaptive two-stage inverse sampling design to estimate density, abundance, and occupancy of rare and clustered populations.

Sampling rare and clustered populations is challenging because of the effort required to find rare units. Heuristically, a practitioner would prefer to discontinue sampling in areas where rare units of interest are apparently extremely sparse or absent. We take advantage of the characteristics of inverse sampling to adaptively inform practitioners when it is efficient to move on to sample new areas. We introduce Adaptive Two-stage Inverse Sampling (ATIS), which is designed to leave a selected area after observation of an a priori number of only non-rare units and to continue sampling in the area when rare units are observed. ATIS is efficient in many cases and yields more rare units than conventional sampling for a rare and clustered population. We derive unbiased estimators of population total and variance. We also introduce an easy-to-compute estimator, which is nearly as efficient as the unbiased estimator. A simulation study on a rare plant population of buttercups (Ranunculus) shows that ATIS even with the easy-to-compute estimator is more efficient than its conventional sampling counterparts and is more efficient than Two-stage Adaptive Cluster Sampling (TACS) for small and moderate final sample sizes. Additional simulations reveal that ATIS is efficient for binary data (e.g., presence or absence) whereas TACS is inefficient for binary data. The overall results indicate that ATIS is consistently efficient compared to conventional sampling and to adaptive cluster sampling in some important cases.

Citizen Science Contributions to Address Biodiversity Loss and Conservation Planning in a Rapidly Developing Region

Biodiversity data support conservation research and inform conservation decisions addressing the wicked problem of biodiversity loss. However, these data often need processing and compilation before use, which exceed the time availability of professional scientists. Nevertheless, scientists can recruit, train, and support a network of citizen scientists to prepare these data using online platforms. Here, we describe three citizen science projects sponsored by the Arkansas Natural Heritage Commission to transcribe and georeference historic herbarium specimens and document current biodiversity through iNaturalist for two highly biodiverse and rapidly developing counties in Northwest Arkansas, USA. Citizen science-generated data will be used in a county natural heritage inventory (CNHI) report, including a comprehensive list of taxa tied to voucher specimens and records for rare plant populations. Since the CNHI project started in 2018, citizen scientists have transcribed 8855 and georeferenced 2636 specimen records. From iNaturalist observations, 125 rare plant populations of 39 taxa have been documented. This CNHI report will determine the most critical taxa, habitats, and sites for conservation action in the region and will inform conservation stakeholders at the local, state, and federal levels as they engage in land acquisition, ecological restoration, natural resource management, planning of growth and development, and environmental review/regulation.

Thirteen Years of Rare Plant Population Changes in the Adirondack Alpine

New York's Adirondack alpine zone harbors many rare vascular plants threatened by climate change, atmospheric deposition, and damage from recreational use. Here, we report on the results of population monitoring at 6-year intervals of 15 alpine areas. We sampled 366, 360, and 369 randomly placed plots in 2006–2007, 2013, and 2018–2019, respectively. Ten species were found in at least 5% of the plots, with Trichophorum cespitosum (Deer's Hair Club Sedge; 60% of plots) and Huperzia appressa (Mountain Firmoss; 42%) most frequent. Of these 10 species, 5 showed significant increases in density over time and 3 had no significant change in density. The 5 species showing increases also had densities positively correlated with metrics of current or former physical disturbance, such as exposure to western slopes and proximity to hiking trails. These data suggest many rare alpine plants are maintaining population levels; environmental heterogeneity and hiker education in the alpine zone may be contributing to this pattern.

No place to hide: Rare plant detection through remote sensing

AbstractAimDetection of rare species is limited by their intrinsic nature and by the constraints associated with traditional field surveys. Remote sensing (RS) provides a powerful alternative to traditional detection methods through the increasing availability of RS products. Here, we assess the capacity of RS at high and medium resolution to detect rare plants with direct and indirect approaches, and how the performance of RS can be influenced by the characteristics of species.MethodsAn extensive literature review was conducted to synthesize the use of RS to detect or predict rare plant occurrence at high and medium resolution (<30 m and 30–300 m, respectively). The concept of “rarity” was based on Rabinowitz's rare species classification. The literature review was performed in Scopus for the period 1990–2020.ResultsWhile direct detection is often limited, it is possible with high and very high spatial resolution data for rare plants with distinctive traits. RS is also able to capture biophysical conditions driving rare plant distributions, which can indirectly provide accurate predictions for them. Both approaches have the potential to discover new populations of rare plants. RS can also feed SAMs of rare plants, which combined with SDMs can provide a valuable approach for rare plant detection. While direct detection is limited by the space occupied by a species within its habitat and its morphological, phenological and physiological characteristics, the predictive performance of RS‐based SDMs (indirect detection) can be influenced by habitat size, habitat specificity and phenological features of rare plants. Similarly, model predictive performance can be influenced by the rarity form of the target species according to the rarity classification criteria.Main conclusions.With this synthesis, the strong potential of RS for the purposes of detection and prediction of rare plant has been highlighted, with practical applications for conservation and management.

The conditions and methods of biological diversity preservation and restoration on post-technogenic lands

Oil production, as well as the transportation of oil and gas through pipeline systems, cause the destruction and man-made transformation of the natural ecosystems of Northern Eurasia, an increase in the area of disturbed lands, and a reduction in the habitats of specially protected plant species. In this regard, the most significant measures for biological diversity are the identification of conditions for the growth of populations of rare plants in man-made biotopes and the development of methods for their conservation and restoration. 12 species (Carex sylvatica, Dactylorhiza baltica, D. fuchsii, D. incarnata, D. maculata, Fragaria moschata, Glyceria lithuanica, Listera ovata, Neottia nidus-avis, Ophioglossum vulgatum, Platanthera bifolia, Veratrum lobelianum) from the Red Book of the Yaroslavl region and 1 species (Dactylorhiza baltica) from the Red Book of the Leningrad region were recorded in the protected area of oil pipelines. Moreover,Dactylorhiza balticais listed in the Red Book of the Russian Federation. ForDactylorhiza fuchsii, D. incarnata, D. maculata, Fragaria moschata, at the risk of complete destruction of their biotopes, methods of their transplantation, repatriation and rehabilitation have been developed and transferred to the appropriate Department of the Yaroslavl region. For the restoration of biotopes on bulk sand dams of an oil field in Western Siberia, an experimental study of the wild speciesLeymus arenarieusas a fixative of technogenic sands showed good results.

Recovery of rare plant populations and species richness on a calcareous floodplain in southwestern Montana

Recovery of rare plant populations and species richness on a calcareous floodplain in southwestern Montana

Phytophthora Introductions in Restoration Areas: Responding to Protect California Native Flora from Human-Assisted Pathogen Spread

Over the past several years, plantings of California native plant nursery stock in restoration areas have become recognized as a pathway for invasive species introductions, in particular Phytophthora pathogens, including first in the U.S. detections (Phytophthora tentaculata, Phytophthora quercina), new taxa, new hybrid species, and dozens of other soilborne species. Restoration plantings may be conducted in high-value and limited habitats to sustain or re-establish rare plant populations. Once established, Phytophthora pathogens infest the site and are very difficult to eradicate or manage—they degrade the natural resources the plantings were intended to enhance. To respond to unintended Phytophthora introductions, vegetation ecologists took a variety of measures to prevent pathogen introduction and spread, including treating infested areas by solarization, suspending plantings, switching to direct seeding, applying stringent phytosanitation requirements on contracted nursery stock, and building their own nursery for clean plant production. These individual or collective actions, loosely coordinated by the Phytophthoras in Native Habitats Work Group ensued as demands intensified for protection from the inadvertent purchase of infected plants from commercial native plant nurseries. Regulation and management of the dozens of Phytophthora species and scores of plant hosts present a challenge to the state, county, and federal agriculture officials and to the ornamental and restoration nursery industries. To rebuild confidence in the health of restoration nursery stock and prevent further Phytophthora introductions, a voluntary, statewide accreditation pilot project is underway which, upon completion of validation, is planned for statewide implementation.

Phytodiversity of the Irgiz Floodplain nature monument

The Bolshoy Irgiz River is 375 km long and has a catchment area of 24 thousand km, including the Orenburg Region and the Samara Region. The flora contains 64 species of plants: 14 belong to the class of monocotyledons (Liliopsida) and 48 belong to the class of dicotyledons (Magnoliopsida), the most numerous families by the number of species are Lamiaceae (5), Cyperaceae (5), Potamogetonaceae (5), Polygonaceae (4), Poaceae (4). The ecological spectrum of the flora is represented by hydrophytes (20 species), helophytes (8), hygrohelophytes (5), hygrophytes (19) and mesophytes (12). These are mainly broad-area species of the Eurasian (23), Holarctic (23) and pluriregional (11) ranges. There are only 7 species of plants with narrow range borders. In economic terms the flora consists of 28 species of medicinal plants, as well as forage (23), tanning (15), food (14), dye (13), honey (12), ornamental (11) and poisonous (8) plants. Vegetation is represented by 17 formations and is represented by the coastal-aquatic vegetation type and two subtypes: coastal and aquatic vegetation. The first subtype contains formations: Phragmiteta australis, Typheta angustifolitae, Scirpeta lacustris, Sagittarieta sagittifoliae, Persicarieta amphibii, Alismateta plantago-aquaticae. The second subtype contains: Nymphaeeta candidae, Nuphareta luteae, Potameta lucentis, Potameta perfoliati, Potameta crispus, Lemneta minori, Salvinieta natantis, Hydrocharieta morsus-ranae, Spirodeleta polyrhizi, Lemneta trisulcae, Ceratophylleta demersi. Coastal plant communities are characterized by a 23-tier structure, a high degree of projective coverage, and a relatively high abundance of species (from 15 to 26). Water phytocoenoses are poor in species composition, have a spotty character of overgrowth and 12 tiered structure. The Irgiz Floodplain nature monument requires compliance with the stipulated protection measures in order to preserve the habitat of rare plant populations Nuhar luteum L., Nymphaea candida J. et C. Presl., Salvinia natans L. (All.), Cicuta virosa L., Najas major All. Descriptions of phytocenoses were carried out according to the generally accepted method of geobotanical research in the summer of 2018, while tiering, abundance, projective cover and vitality were noted as well as all species included in plant communities were registered.

Genetic monitoring to assess the success of restoring rare plant populations with mixed gene pools.

Increasing genetic diversity and maintaining evolutionary processes are primary goals of conservation translocations, which involve the intentional movement of an at-risk species to establish new populations or augment existing populations, with the ultimate goal of reversing declines. Much debate has focused on how to select source material for plant translocations, with early approaches focusing primarily on maintaining the genetic uniqueness of populations. However, recent strategies often advocate mixing population sources during translocation to increase genetic diversity and re-establish connectivity. Yet, despite hundreds of translocations programmes with at-risk plant species presently underway (e.g. Silcock et al., 2019), few studies have conducted thorough assessments of the effects of mixing population sources on both the genetic diversity and fitness of translocated populations. The study by Van Rossum et al. (2020) in this issue of Molecular Ecology uses detailed assessments of genetic parameters and fitness to understand the outcomes of mixing two genetically differentiated source populations in translocations of the rare, self-incompatible perennial herb, Arnica montana, whose populations are declining at low elevations in Western Europe. They examine genetic changes throughout the translocation process (source populations to F1 offspring) and demonstrate the maintenance of high genetic diversity in successive generations for all three translocations. Translocated populations exhibited high contemporary pollen flow, substantial admixture between source populations and low inbreeding in F1 offspring. Importantly, they found no evidence of outbreeding depression in F1 offspring. This work shows that genetically mixing source populations can result in optimal genetic outcomes in translocations of declining plant species and exemplifies how multigenerational genetic monitoring and fitness assessments can be used to evaluate the success of experimental translocations.

SOZOPHYTES IN POSTMINING LANDSCAPES OF KRYVYI RIH BASIN

Introduction. Traditionally, lands transformed by mining operations are considered destabilized and environmentally hazardous. However, the experience of natural researches of Kryvyi Rih Basin showed that over time post-mining territories (those that emerged after the completion of mineral extraction and enrichment) become the arena of formation of secondary ecosystems, the development of which is the subject to the general natural laws. There, within vegetation communities, populations of rare plants, which are included into “conservation lists” of various ranks, are forming.Aim. To define the sozophyte fraction of phytobiota of post-mining territories of Kryvyi Rih Basin and to carry out ecological-coenotical analysis of this fraction.Methods. A list of the sozophytes was completed basing on multiple surveys of quarry-dump complexes of Kryvyi Rih Area. In its formation, the materials of the Red Book of Dnipropetrovsk Region, the Red Book of Ukraine, the latest editions of the World and European Red Lists have been analyzed. The analysis of the eco- and coenomorphic structure of the composition of the sozophytes was carried out using the monographic work by V.V. Tarasov, as well as the characteristics of species from the Red Book of Dnipropetrovsk Region. Determination of life strategies of species was carried out in accordance with the concept of L.G. Ramenskiy – J. Grime.Results. We found that 27 species of flora of anthropogenic ecotopes included in the World and European Red Lists are widespread in the region. There is no threat to the existence of such species today, and it does not make sense to include them in the conservation lists. Instead, the list of sozophytes included 40 species from the “red books” of the lower ranks: one belongs to Ascomycota, one to Marchantiophyta, 4 – to Polypodiophyta and 34 to Magnoliophyta (19 families, 27 genera). The composition of the sozophyte fraction of phytobiota of waste man-made objects is dominated by patients (S-strategists), steppants and petrophytes, xerophytes, heliophytes, mesotrophs.Conclusion. Post-mining territories undergo much less anthropogenic interference than the remnants of natural ecosystems of Kryvyi Rih Area, so they are refugia of rare phytodiversity in the technogenically transformed region. Of the sozophyte fraction, 32 species settled here spontaneously, 4 – naturalized after introduction during reclamation experiments, and 4 more – established by both ways.Key words: sozophytes; phytobiota; post-mining landscapes; ecological-coenotical analysis; refugia; Kryvyi Rih Area.

Mixing source populations increases genetic diversity of restored rare plant populations

The genetic diversity of germplasm used in reintroduction and restoration efforts can influence how resulting populations establish, reproduce, and evolve over time, particularly in disturbed and changing conditions. Regional admixture provenancing, mixing seeds derived from multiple populations within the same region as the target site, has been suggested to produce genetically diverse germplasm. Yet little empirical evidence shows how genetic diversity in germplasm resulting from this approach compares to source populations, or how it varies in restored populations. Here, we use neutral molecular markers to follow genetic diversity through production and use of germplasm when mixing multiple source populations in nursery production beds. Castilleja levisecta is a rare species experiencing inbreeding depression in remaining populations, with a federal recovery plan requiring the re‐establishment of populations in areas where it has been extirpated. Specifically, we track diversity from wild‐collected source populations through different production approaches and reintroductions using two propagule types. We show that measures of genetic diversity, inbreeding, and relatedness change during the production and use of material produced with a regional admixture provenancing approach, with the step at which source populations are mixed and germplasm type used influencing whether all source populations are equally represented. While genetic diversity increased throughout the process, inbreeding and relatedness increased in nursery production beds but decreased in reintroductions, with the lowest inbreeding and relatedness in populations restored using seeds rather than plugs. The results highlight the importance of taking an integrated approach informed by research when planning and implementing reintroductions with mixed‐source germplasm.

Nonadditive effects among threats on rare plant species.

The current loss of biodiversity has put 50,000 plant species at an elevated risk of extinction worldwide. Conserving at-risk species is often complicated by covariance or nonadditivity among threats, which makes it difficult to determine optimal management strategies. We sought to demographically quantify covariance and nonadditive effects of more threats on more rare plant species than ever attempted in a single analysis. We used 1082 population reports from 186 populations across 3 U.S. states of 27 rare, herbaceous plant species collected over 15 years by citizen scientists. We used a linear mixed-effects model with 4 threats and their interactions as fixed predictors, species as a random predictor, and annual growth rates as the response. We found a significant 3-way interaction on annual growth rates; rare plant population sizes were reduced by 46% during the time immediately after disturbance when populations were also browsed by deer (Odocoileus virginianus) and had high levels of encroachment by woody species. This nonadditive effect should be considered a major threat to the persistence of rare plant species. Our results highlight the need for comprehensive, multithreat assessments to determine optimal conservation actions.

The Demography of Gentiana autumnalis in Populations Under Varying Management Regimes in New Jersey

Gentiana autumnalis (pine barren gentian) is a rare, fall-flowering perennial that is endemic to pine barren habitat from New Jersey to South Carolina. This disturbance-adapted, early successional species is at risk in New Jersey as a result of human interactions, namely growing season mowing and fire suppression. We used a repeated measures design to compare the differences between managed (mowing and prescribed fire) and unmanaged G. autumnalis populations for density, life stage, mortality, and fecundity. Managed populations had a greater gentian density, proportion of reproductive individuals, and seedlings compared to unmanaged populations. Implementing prescribed burns and mowing at previously unmanaged sites prior to spring growth increased gentian density, flowering, and seed set the same year. Our data support that prescribed burning and mowing can be beneficial management tools for the conservation of G. autumnalis and other disturbance-adapted species that require open early-successional habitat. However, their implementation can have negative consequences if conducted during the growing season, especially for roadside populations that are periodically mowed. Declining rare plant populations have the potential to benefit from management practices that facilitate ideal growing conditions and influence life stage transitions that will best improve population growth rate over time.