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Article

Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation

by
Fernando Forster Furquim
1 and
John Derek Scasta
2,*
1
Graduate Program in Botany, Universidade Federal do Rio Grande do Sul, Porto Alegre 91540-000, Brazil
2
Department of Ecosystem Science, Laramie Research and Extension Center, University of Wyoming, Laramie, WY 82072, USA
*
Author to whom correspondence should be addressed.
Diversity 2025, 17(4), 248; https://doi.org/10.3390/d17040248
Submission received: 31 October 2024 / Revised: 27 February 2025 / Accepted: 19 March 2025 / Published: 30 March 2025
(This article belongs to the Section Biodiversity Conservation)
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Abstract

:
Conservation of rare plant species diversity is often found within the context of disturbance and land use planning. In mountainous regions, globally, critical plant conservation issues can occur at esthetically pleasing topoedaphic positions, such as popular mountain summits. Here, we assess the spatiotemporal ecology of an imperiled cushion plant assemblage in such a situation. Plant community dynamics of three rare cushion plant species [scented pussytoes (Antennaria aromatica), Howard’s alpine forget-me-not (Eritrichum howardii), and Shoshone carrot (Shoshonea pulvinata)] were measured at a 2475 m mountain summit near Cody, WY, USA. The survey was conducted in the summer of 2017–2019 using 1 m2 quadrats across three macroplots (ranging from 295 to 2250 m2 in size) to estimate all vascular plant species abundance. Altitude, canopy height, vegetative cover, standing dead biomass, rock, litter, and bare soil were also measured. We assessed annual changes in abundances, richness (#), evenness (N2/N1), and diversity (H′) and performed a constrained ordination to understand ecological drivers of distribution. Nineteen total plant species were identified, all of which were native perennial species. Five additional species were also noted to be species of conservation concern. For the three rare cushion plants of focus, abundance did not significantly change over the three-year period. Species richness was lower in 2017 than in subsequent years, but there was no difference in evenness or diversity. In the constrained ordination, the first axis explained 56.1% of the variation and was attributed to the rock-to-vegetation gradient of the environment, while the second axis explained an additional 28.7% of the variance and was attributed to altitude. The three rare cushion plants of focus appeared to segregate and occupy differential habitat niches. The popularity of this mountain peak, coupled with the presence of a diverse rare cushion plant community, should facilitate the careful monitoring and management of tourism to ensure the conservation of diversity.

1. Introduction

Conservation of rare plant species, which are important contributors to global ecological diversity, is often found in the context of land use planning because these species can occur at popular tourism sites such as mountain peaks [1]. Here, society and rare plant species conservation acutely intersect because mountain peaks are small and isolated but are frequented by humans more than the surrounding landscape. The popularity of esthetic sites such as mountain peaks offers experiences in nature that have important cultural and socioecological value [2,3,4]. Such concentrations of humans at high-value conservation sites (i.e., “ecotourism”) have been increasing in demand since the 1980s [5], which may lead to concern for how to balance human demand and endangered species diversity and conservation in these places [1,6].
Globally, nature-based tourism can impact vegetation by human trampling through reductions (temporary or permanent) in height, cover of species, and/or disruption of plant cycles [7,8,9]. Continuous human disturbance can change botanical composition and diversity by favoring disturbance-resistant species and reducing the presence of more sensitive species, which may be rare [10]. Human recreational access can also lead to the introduction of exotic species, some of which may be invasive, and should inform how such access is designed [11]. Designs for recreational access may incorporate the ecological resistance capability of an area [12]. As a contradiction, ecotourism can also, at times, contribute to the preservation of native species diversity by the demarcation of new protected areas and by educating people about environmental issues and ecological value [13,14,15]. However, naturally fragmented and isolated populations that occur in special and discrete habitats such as mountain peaks have been lacking in description and protection [16,17]. Ultimately, human influence on endangered plants and diversity in naturally fragmented and isolated populations of limited spatial extent need additional attention for many reasons, but also for the potential for cascading ecological effects [16,17,18].
An example of such a ‘human-endangered plant interaction’, with implications for diversity conservation, occurs at The Heart Mountain Ranch Preserve (HMRP)—a property owned and managed by The Nature Conservancy (TNC) north of Cody, Wyoming, USA. TNC’s primary mission is to conserve biodiversity and increase public awareness of conservation issues. HMRP is the location of Heart Mountain with a hiking trail that includes a summit at the peak of Heart Mountain, with geologic features that support a cushion plant community, including rare species of conservation concern (henceforth ‘focal’ species) such as aromatic pussytoes (Antennaria aromatica Evert; Subnational Heritage Rank S3 ‘vulnerable’), Howard’s alpine forget-me-not (Eritrichium howardii (A.Gray) Rydb.; Subnational Heritage Rank S2 ‘imperiled’), and Shoshonea (Shoshonea pulvinata Evert & Constance; Subnational Heritage Rank S2 ‘imperiled’ in Wyoming and S1 in Montana ‘critically imperiled’) [19,20,21] (Figure 1). All three species have been classified as a ‘species of concern’ by the Wyoming Natural Diversity Database (WYND; https://wyndd.org/species_list/ (accessed on 28 October 2024)), but their overlap in distribution is currently not well defined. A. aromatica is a species of potential concern with limited spatial distribution that could become vulnerable in the future if there are large-scale landscape changes [21,22,23,24]. E. howardii and S. pulvinata are of even greater conservation concern due to a much more constrained landscape distribution, and S. pulvinata was a candidate for listing under the Endangered Species Act in 1985 [21,25,26,27,28,29].
Even though these three rare cushion plant species were generally described by Heidel in 2012 [21], with robust consideration for taxonomy [22,23,24,25,29] with a few referencing their elevational ranges, there are no published references describing species associations, which is extremely important for their conservation. According to Wiser et al. 1998 [30], environmental characteristics and botanical composition of sites wherein rare and endangered species occur can be integrated into management strategies to identify unknown populations, assess site potential for restoration or reintroduction, predict impacts of habitat degradation, and guide future research aiming to optimize species conservation and diversity.
In this study, we aimed to characterize the spatiotemporal ecology of an imperiled cushion plant assemblage at a popular mountain summit in the North American Rocky Mountains. To accomplish this, we sought to (1) quantify plant community diversity and determine if exotic species invasion or other rare plants were of concern; (2) determine if rare species abundance and overall plant species richness, evenness, and diversity were stable over a three year period; (3) quantify the habitat preferences of each rare plant species and determine if niche separation occurred; and (4) provide insight for future management to optimize botanical diversity conservation and societal awareness. This study therefore seeks to describe populations of three rare species but also explore community-level interactions.

2. Materials and Methods

The Heart Mountain Ranch (44°41′ N, 109°00′ W) is situated in the Bighorn Basin in Park County, Wyoming (Figure 2). This ranch is property of the Wyoming Chapter of The Nature Conservancy. The Bighorn Basin is a 161 km wide intermontane basin surrounded by mountain ranges (i.e., Absarokas to the west, Pryors to the north, Big Horns to the east, and the Owl Creek and Bridger ranges to the south) and, because of it, a rain shadow covers it, making it one of the most arid areas in Wyoming. The long-term (1895–2022) annual precipitation is 318.5 mm, and the annual temperature is 5.0 °C. During our period of study (2017–2019), precipitation was observed to be above the long-term average (384, 379, 459 mm), and the temperatures bracketed the long-term average (5.9 °C, 5.5 °C, and 4.5 °C) [31]. The Bighorn Basin is characterized by multi-colored badlands as well as gravelly arid soils that tend to have sandy subsoils [32]. The altitude from the base to the top of the mountain ranges from 1524 to 2476 m. The vegetation is dominated by trees but contains patches with graminoids, forbs, and shrubs. Furthermore, the presence of rock outcrops and canyons is prominent.
A search by walking from the base to the top of Heart Mountain was carried out in June 2017 to find potential locations with the rare focal plant species. This search was conducted within the reported elevation ranges of 1372–2928 m for A. aromatica [22,23] and 1770–2780 m for S. pulvinata [24,26]. No reported ranges were found in the literature for E. howardii. These locations, referred to as macroplots (n = 3) in our study, were marked with a GPS using the Universal Transverse Mercator (UTM) system after initial scouting and identification, and their vegetation and ecological features were sampled consistently in 2017, 2018, and 2019 using quadrats of 1.0 m2 in size (1.0 m × 1.0 m) distributed along each macroplot area, with 6 to 9 quadrats per microplot [33] (Table 1). Specifically, each vascular plant species inside the plot was identified to the lowest possible taxonomic level, and unknown specimens were collected and later identified using Dorn 2001 [34] with contemporary reference to taxonomic nomenclature and authority adhering to the United States Department of Agriculture—Plants Database (https://plants.usda.gov/home (accessed on 25 October 2024)). To estimate the abundance of each vascular plant species, we used a modified decimal scale [35] with 7 classes of plant cover (<1%; 1–5%; 5–15%; 15–25%; 25–50%; 50–75%; 75–100%). Ecological predictors that were measured included structural components of vegetation, and other ecological features (i.e., vegetative cover, standing dead biomass, rock, litter, and bare soil) were also measured using the same decimal scale. The height of the canopy was the average of five heights within each plot measured randomly using a graduated ruler. The selection of predictors used in the analyses was based on the species’ natural history [21,22,23,24,25,26,27,28,29] and the potential environmental alterations attributed to ecotourism [1,6,8,10,11,12,13]. Gradients for these environmental predictors were as follows: vegetative cover (5 to 52%), standing dead biomass (0 to 10%), rock (10 to 93%), litter (0 to 15%), bare soil (0 to 60%), canopy height (0.25 to 10.2 cm), and altitude (2301 to 2478 m).
In order to ensure that the area was sufficiently sampled, we created a species accumulation curve using 10,000 permutations via the random method (i.e., which encounters sites in random order and samples individuals without replacement) [36] using the specaccum function R ‘vegan’ package [37,38] (see Figure 3). This suggests that our 3 macroplots, with a total of 24 quadrats, were robust for sampling effort and desired species detection.
In order to determine if the three focal rare cushion plant species changed during our three-year study, we ran mixed-effects analysis of variance (ANOVA) models with the proportional abundance of each species as the dependent variable, year as the main fixed effect, and quadrat nested within macroplot as a random effect to account for the nested and repeated sampling design through time. We ran similar fixed effect models for species richness (#), evenness (N2/N1), and diversity (Shannon–Wiener index, H′). Proportional abundances were arcsine transformed before analysis to account for issues of variance heteroscedasticity and normality. Analyses were accomplished in R using the lmer function [38,39].
Finally, in order to identify and interpret patterns of distribution, we performed a Canonical Correspondence Analysis (CCA) projecting onto the ordination biplot the species centroids and environmental variables as vectors (i.e., altitude, canopy height, vegetative cover, standing dead biomass, rock, litter, and bare soil). We ran a Monte-Carlo simulation with 1000 iterations to determine the significance of the first axis and then all four ordinal axes, as well as calculating pseudo-canonical correlations for the first and second axis. We then displayed the relative abundance of the three focal species at the plot scale in constrained multivariate space in a symbol plot relative to macroplots. Multivariate analysis was conducted using CANOCO version 5 statistical software (Ithaca, NY, USA) [40].

3. Results

Nineteen vascular plant species were identified in the study plots (Table 2). All plants were native and perennial, and the majority were forbs (14 of 19). Only three grass species (Festuca idahoensis, Leucopoa kingii, and Poa glauca), one shrub species (Kelseya uniflora), and one tree species were identified (Pinus flexilis). Of the species found, at least five additional plant species (other than A. aromatica, E. howardii, and S. pulvinata) were noted to be species of concern based on a review of the WYNDD species list (Table 2). These include Antennaria monocephala (WYNDD SOC), K. uniflora (Heritage State Rank S2 = imperiled), Lomatium attenuatum (WYNDD SOC; Heritage State Rank S2 = imperiled), Packera werneriifolia (Heritage State Rank S2 = imperiled), and P. flexilis (WYNDD SOPC; USFS Species of Local Concern BlkHlNF). Thus, 8 of 19 plant species (~42%) in these communities are species of conservation concern. Several of these species demonstrate a similar growth habit to our rare focal cushion plant species, which are characterized by a low physical structure. They include pygmy pussytoes (A. monocephala), oneflower kelseya (K. uniflora), taptertip desertparsley (L. attenuatum), and hoary groundsel (Packera wernerifolia), all of which have a Heritage State Rank (HSR) of 2, indicating ‘imperiled’. In addition, several of these are Wyoming state-designated species of concern (SOCs).
Of the three focal cushion plant species, S. pulvinata demonstrated the highest proportional abundance through time (proportions ranging from 0.06 to 0.10 or 6% to 10%), followed by A. aromatica (proportions ranging from 0.01 to 0.02 or 1% to 2%), with E. howardii showing the lowest proportional abundance (always <0.01 or <1%) (Figure 3). There was no year effect on abundance for any of the species (all p-values > 0.05) (Figure 4).
For species richness, evenness, and diversity, there was no year effect for evenness (p = 0.051) or diversity (0.106) but there was for species richness (0.009) which was significantly lower in 2017 than in 2018 or 2019 (Figure 5).
In the constrained ordination, the first axis explained 56.1% of the variation and was attributed to the rock-to-vegetation gradient of the environment, while the second axis explained an additional 28.7% of the variance (for a total of 84.8% of the total variance explained in the botanical data) which could be attributed to the altitudinal gradient which was likely related to SDB and height (Figure 6). The three focal cushion plant species each appeared to have differential habitat niches. A. aromatica was closely and positively oriented to the vector for altitude, suggesting that its abundance increases as altitude increases. E. howardii was also distinct in ordination space with an opposite orientation with altitude, suggesting it occurs at lower elevations in this study area. S. pulvinata, however, was most closely oriented with a positive increase in rocks, which was divergent from bare soil and litter cover. For the other plant species discovered to be of conservation concern, 3 had a strong affinity for rock cover, including A. monocephala, K. uniflora, and L. attenuatum. One of the species had a negative association with rock cover and a niche for vegetative cover, and another species, the only tree in the study area, P. flexilis, had a strong association with SDB. The biplot from the ordination also suggests that the three focal species do not mutually co-occur within the study area, but rather, distribution at this scale is heterogeneous based on different habitat niches and occupancy patterns (Figure 7).

4. Discussion

Except for plant species richness, which was lower in the first survey year than others, the general abundance of the three focal rare cushion plant species, as well as all metrics of evenness and diversity, appeared to be stable during our three-year period of study. This is important given the limited distribution in terms of the geographical range of these species and the critical concern about population sustainability and temporal variability of rare plants in general [41]. In addition, the persistence of these species in the context of their physical occurrence near the summit of a popular mountain peak that is open to the public (i.e., an indication of habitat vulnerability) suggests that recreation was managed appropriately during the period of study [5,16]. However, three years have admittedly limited temporal insight to detect population changes. We therefore suggest that the annual monitoring of these rare cushion plant species should be a regular part of the monitoring and management plan for the property [42]. Given the threat of climate change to alpine mountain summits, regular monitoring may be increasingly important given additional species of conservation concern occurring here [43]. Moreover, given the role of anthropogenic disturbance in our study site, such monitoring for exotic species will be important because we have not found any exotic species in the study plots as of yet [44,45].
The three focal cushion plant species, while generally co-existing in the larger area, did not uniformly occupy habitat features as indicated by segregation along different ecological axes [46]. Some species displayed more constrained or smaller niches with clear explanatory ecological variables predicting presence and abundance, while others were more generally distributed. Such functionally distinct assemblages could be an indication of the differential growth, biomass allocation, and resource acquisition traits influencing community assembly [47]. This study is the first report to our knowledge that has documented such ecological complexities of these rare focal cushion plant species simultaneously and has moved beyond general taxonomic and botanical descriptions [21].
The intersection of rare plant diversity conservation with nature-based tourism, a dynamic interaction present in our study site, is a recognized challenge globally [11,48,49]. Moreover, popular tourism hotspots such as mountain summits have been recognized as areas where botanical diversity is particularly vulnerable due to human-caused soil compaction, erosion, and other disturbances, which have been characterized as tourists “swarming to the summit” [50]. Our study, coupled with the highlighted risk noted in the published literature, suggests that regular monitoring, data-based management decisions, and education may all be necessary for conserving such rare cushion plant species that evolved in these harsh and discrete environments [7,8,9,11]. Such examples in the general Rocky Mountain region of the U.S. include the alpine tundra in Rocky Mountain National Park, where losses due to trampling have been clearly noted [51]. Importantly, negative impacts on rare forbs could have cascading collateral effects on other trophic levels, such as pollinator species such as butterflies and bees [15]. Finally, the importance of cushion plants as contributors to ecological diversity in extreme mountain summit environments has been noted as a characterizing botanical functional group [52,53] needing additional attention as climate change continues to impact limiting stress factors and cushion plant microclimates [54].

Author Contributions

J.D.S. and F.F.F. equally contributed to conceptualization, methodology, formal analysis, data curation, writing—original draft preparation, and writing—review and editing. J.D.S. led supervision and project administration, and F.F.F. led the field sampling. All authors have read and agreed to the published version of the manuscript.

Funding

This research received in-kind support from The Nature Conservancy for housing of field staff.

Institutional Review Board Statement

Not applicable.

Data Availability Statement

Data can be made available upon reasonable request.

Acknowledgments

We thank Carrie and Brian Peters at The Nature Conservancy’s Heart Mountain Ranch Preserve for field and lodging support.

Conflicts of Interest

The authors declare no conflicts of interest. The funders had no role in the design of the study; in the collection, analyses, or interpretation of data; in the writing of the manuscript; or in the decision to publish the results.

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Figure 1. (A) General environment, (B) aromatic pussytoes (Antennaria aromatica), (C) Howard’s alpine forget-me-not (Eritrichum howardii), and (D) Shoshonea (Shoshonea pulvinata).
Figure 1. (A) General environment, (B) aromatic pussytoes (Antennaria aromatica), (C) Howard’s alpine forget-me-not (Eritrichum howardii), and (D) Shoshonea (Shoshonea pulvinata).
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Figure 2. Heart Mountain study area (A) location (black filled triangle); (B) landscape view; and (C) satellite imagery of macroplots location.
Figure 2. Heart Mountain study area (A) location (black filled triangle); (B) landscape view; and (C) satellite imagery of macroplots location.
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Figure 3. Species accumulation curve using 10,000 permutations using the random method (i.e., which encounters sites in random order and samples individuals without replacement) to determine sampling effort and optimal species detection in an imperiled cushion plant assemblage.
Figure 3. Species accumulation curve using 10,000 permutations using the random method (i.e., which encounters sites in random order and samples individuals without replacement) to determine sampling effort and optimal species detection in an imperiled cushion plant assemblage.
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Figure 4. Annual means (±95% confidence intervals) of the three rare species of primary concern [scented pussytoes (Antennaria aromatica), Howard’s alpine forget-me-not (Eritrichum howardii), and Shoshone carrot (Shoshonea pulvinata)]. Statistical analyses based on mixed analysis of variance (ANOVA) models with each rare plant species proportion with an arcsine transformation as the dependent variable, year as the main fixed effect, and quadrat nested within macroplot as a random effect to account for the nested and repeated sampling design with differences determined at α = 0.05.
Figure 4. Annual means (±95% confidence intervals) of the three rare species of primary concern [scented pussytoes (Antennaria aromatica), Howard’s alpine forget-me-not (Eritrichum howardii), and Shoshone carrot (Shoshonea pulvinata)]. Statistical analyses based on mixed analysis of variance (ANOVA) models with each rare plant species proportion with an arcsine transformation as the dependent variable, year as the main fixed effect, and quadrat nested within macroplot as a random effect to account for the nested and repeated sampling design with differences determined at α = 0.05.
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Figure 5. Mean (±standard error) plant (a) richness, (b) evenness, and (c) diversity for 2017, 2018, and 2019. Statistical analyses based on mixed analysis of variance (ANOVA) models with each diversity metric as the dependent variable, year as the main fixed effect, and quadrat nested within macroplot as a random effect to account for the nested and repeated sampling design with differences determined at α = 0.05 and indicated by differing letters (a and b).
Figure 5. Mean (±standard error) plant (a) richness, (b) evenness, and (c) diversity for 2017, 2018, and 2019. Statistical analyses based on mixed analysis of variance (ANOVA) models with each diversity metric as the dependent variable, year as the main fixed effect, and quadrat nested within macroplot as a random effect to account for the nested and repeated sampling design with differences determined at α = 0.05 and indicated by differing letters (a and b).
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Figure 6. Constrained multivariate analysis using Canonical Correspondence Analysis (CCA) displaying species’ centroids and environmental variables as vectors. Circles (●) indicate forbs, triangles (▲) indicate grasses, squares (■) indicate shrubs, and diamonds (◆) indicate trees.
Figure 6. Constrained multivariate analysis using Canonical Correspondence Analysis (CCA) displaying species’ centroids and environmental variables as vectors. Circles (●) indicate forbs, triangles (▲) indicate grasses, squares (■) indicate shrubs, and diamonds (◆) indicate trees.
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Figure 7. Relative abundance of the three rare species of primary concern [(A) scented pussytoes (Antennaria aromatica), (B) Howard’s alpine forget-me-not (Eritrichum howardii), and (C) Shoshone carrot (Shoshonea pulvinata)] at the plot scale in multivariate space in a symbol plot relative to macroplots. The size of the circle indicates relative abundance; the three colors indicate the three different macroplots and the plus sign indicates the species did not occur in that plot.
Figure 7. Relative abundance of the three rare species of primary concern [(A) scented pussytoes (Antennaria aromatica), (B) Howard’s alpine forget-me-not (Eritrichum howardii), and (C) Shoshone carrot (Shoshonea pulvinata)] at the plot scale in multivariate space in a symbol plot relative to macroplots. The size of the circle indicates relative abundance; the three colors indicate the three different macroplots and the plus sign indicates the species did not occur in that plot.
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Table 1. Geographic coordinates, altitude, area, and number of plots for macroplots.
Table 1. Geographic coordinates, altitude, area, and number of plots for macroplots.
MacroplotLatitudeLongitudeAltitude (m)Area (m²)Quadrats (n)
146°40.035′111°06.996′23042956 *
245°39.914′110°06.840′233422509
345°39.961′110°07.192′24787009
* Lower number of quadrats of macroplot 1 is a function of the smaller area available for sampling.
Table 2. Family, scientific name, common name, characteristics, and conservation status of vascular plant species identified in macroplots. All species are native perennials and plant nomenclature adheres to the United States Department of Agriculture—Plants Database (https://plants.usda.gov/home (accessed on 25 October 2024)) and Conservation Status derived from the Wyoming Natural Diversity Database (WYNDD) Species List (https://wyndd.org/species_list/ (accessed on 28 October 2024)). The list is organized alphabetically by genus and then species.
Table 2. Family, scientific name, common name, characteristics, and conservation status of vascular plant species identified in macroplots. All species are native perennials and plant nomenclature adheres to the United States Department of Agriculture—Plants Database (https://plants.usda.gov/home (accessed on 25 October 2024)) and Conservation Status derived from the Wyoming Natural Diversity Database (WYNDD) Species List (https://wyndd.org/species_list/ (accessed on 28 October 2024)). The list is organized alphabetically by genus and then species.
FamilyScientific NameCommon NameT 1Conservation Status 2
AsteraceaeAntennaria aromaticascented pussytoesFHSR S3, FS SPLC, WYNDD SOC
AsteraceaeAntennaria monocephalapygmy pussytoesFHSR S2, WYNDD SOC
CaryophyllaceaeArenaria hookeri 3Hooker’s sandwortFSpecies not ranked
FabaceaeAstragalus spatulatustufted milkvetchFHSR S5
ScrophulariaceaeCastilleja angustifolia 4northwestern indian paintbrush FHSR S5
BoraginaceaeEritrichium howardiiHoward’s alpine forget-me-notFHSR S2, FS SPLC, WYNDD SOC
AsteraceaeErigeron ochroleucusbuff fleabaneFHSR S4
PoaceaeFestuca idahoensisIdaho fescueGHSR S4/S5
SaxifragaceaeHeuchera parvifolialittleleaf alumrootFHSR S5
RosaceaeKelseya unifloraoneflower kelseyaSHSR S2
PoaceaeLeucopoa kingii 5spike fescueGHSR S5
ApiaceaeLomatium attenuatumtapertip desertparsleyFHSR S2, WYNDD SOC
CaryophyllaceaeMinuartia nuttallii 6Nuttall’s sandwortFHSR S4/S5
AsteraceaePackera canawoolly groundselFHSR S5
AsteraceaePackera werneriifoliahoary groundselFHSR S2
PolemoniaceaePhlox hoodiispiny phloxFHSR S5
PinaceaePinus flexilislimber pineTHSR S4, FS SPLC, WYNDD SPOC
PoaceaePoa glaucaglaucous bluegrassGHSR S3/S4
ApiaceaeShoshonea pulvinataShoshone carrotFHSR S2-WY S1-MT; FS-R2, WYNDD SOC
1 T = type (F = forb, G = grass, S = shrub, and T = tree); 2 conservation status: HSR = heritage state rank (1 = critically imperiled, 2 = imperiled, 3 = vulnerable, 4 = apparently secure, and 5 = secure); FS SPLC = forest service—species of local concern; WYNDD SOC = Wyoming Natural Diversity Database—Species of Concern; 3 synonym Eremogone hookeri; 4 synonym Castilleja integra; 5 synonym Festuca kingii; 6 synonym Sabulina nuttallii.
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MDPI and ACS Style

Furquim, F.F.; Scasta, J.D. Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation. Diversity 2025, 17, 248. https://doi.org/10.3390/d17040248

AMA Style

Furquim FF, Scasta JD. Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation. Diversity. 2025; 17(4):248. https://doi.org/10.3390/d17040248

Chicago/Turabian Style

Furquim, Fernando Forster, and John Derek Scasta. 2025. "Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation" Diversity 17, no. 4: 248. https://doi.org/10.3390/d17040248

APA Style

Furquim, F. F., & Scasta, J. D. (2025). Spatiotemporal Ecology of an Imperiled Cushion Plant Assemblage at a North American Rocky Mountain Summit: Implications for Diversity Conservation. Diversity, 17(4), 248. https://doi.org/10.3390/d17040248

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