Juncus Trifidus Research Articles

Widespread plant species temporal variation along environmental and microclimate gradients in Norwegian mountains in a climate change context

The effect of climate change on mountain vegetation is influenced by environmental factors and site effects. To monitor the effect of climate change we therefore need to understand species' sensitivity to microclimate and environmental gradients. The objective of this study is to study widespread plant species' temporal and spatial variation along environmental and microclimate gradients in Norwegian mountains along a coast–inland gradient. Occurrence and abundance of plant species were surveyed in 110 study plots in four mountains at two points in time, seven years apart. Of the 222 plant species registered, Salix herbacea, Phyllodoce caerulea, Carex bigelowii, Juncus trifidus, Vaccinium myrtillus, Avenella flexuosa, and Empetrum nigrum were widespread across all mountains. These species responded differently to environmental and microclimate gradients, and abundance data were more sensitive than occurrence data. During the short time span we observed some indications of response which might support the assumption that boreal species outcompete alpine species in the forest transition zone, but our data do not indicate this effect at higher altitudes. Monitoring of climate change in mountains needs to include plots along environmental and microclimate gradients as well as an abundance of a set of widespread plant species that represent regional, local environmental, and climate gradients. However, when monitoring perennial plant species, the need for long‐term monitoring projects is high because such species develop slowly over several decades.

Mutual influence and conjugation between populations of alpine phytocoenoses in the Ukrainian Carpathians

The results of studies of association and mutual influence between populations of plant species of the most common alpine phytocenoses in the Ukrainian Carpathians are shown in this work. Considering objects of the research such species have been taken into account: Calamagrostis villosa, Campanula alpinа, Carex curvula, C. sempervirens, Deschampsia cespitosa, Festuca airoides, Helictotrichon versicolor, Hieracium alpinum, Homogyne alpina, Juncus trifidus, Leontodon croceus, Ligusticum mutellina, Loiseleuria procumbens, Nardus stricta, Potentilla aurea, Rhododendron myrtifolium, Sesleria coerulans, Soldanella hungarica, Vaccinium myrtillus, V. uliginosum, V. vitisidaea. Typical alpine groups, which are located in the highest mountain range of the Ukrainian Carpathians - Chornohora in the range of altitude from 1750 m above sea level to peaks over 2000 m, have been researched in this work. The method of studying interactions based on the definition of conjugate occurrence and association in the mutual arrangement of species is applied. All neighboring individuals have been counted around individuals of the active species. The obtained data has been compared with the population density of these species in the contours of the studied phytocenosis area. If neutral interactions between species is considered, then the percentage ratio of individuals in populations, established by the neighborhood, should correspond to their percentage the ratio established by the average density in the phytocenosis. Significant deviations indicate mutual influence or association between species The existence of active interaction between most plant species of the alpine zone was found. Dominants of alpine phytocenosis express neutral or weak interaction among themselves. Asectatory species are less competitive, but more flexible in terms of occupying free ecological niches. A negative interaction is often found between dominants and asectators. The nature of the interaction between the same species can vary in different coenoses. In most cases the presence of plant species, which are considered as positive neighbors, creates prerequisites for colonization of areas. In addition to dominants, it is advisable to use Helictotrichon versicolor in particular, which successfully occupies unsown areas and has a positive interaction with many plant species, in order to restore phytocenoses of the alpine belt, where the turf cover has been disturbed.

Fungal endophytes of stems and roots of Juncus trifidus ssp. trifidus from Poland

Paraconiothyrium, Aureobasidium pullulans, Clonostachys rosea, Oidiodendron griseum, Penicillium miczynskii, Alternaria chartarum, Trichoderma viridescens, Umbelopsis autotrophica and Hyaloscypha finlandica have been isolated from the roots of the highland rush (Juncus trifidus L.) from Babia Gora Massif and the Tatra Mts. in the Western Carpathians. Only the Paraconiothyrium sp. was found both in roots and stems and thus can possibly be transferred from the roots to the leaves (or in opposite direction).

Трансформаційні процеси в альпійських фітоценозах Українських Карпат за умов заповідання та кліматичних змін

Typycal alpine phytocoenoses of Ukrainian Carpathians with dominant species Festuca supina, Carex curvula, Juncus trifidus, Vaccinium uliginosum, Rhododendron myrtifolium, Sesleria coerulens and open chionophilous communities were investigated. As a result of comparative studies during 1982–2021, among alpine phytocoenoses, the smallest changes in the structure, abundance and coenose-forming positions of species were found in communities dominated by Juncus trifidus, Vaccinium uliginosum, Rhododendron myrtifolium and Sesleria coerulans, in particular in the Juncetum cetrario-myrtillosum, Uliginetum cetrariosum, Rhodoretum calamagrostiosum and Seslerietum cariceto-festucosum communities. During the same period in communities with dominant Festuca supina and Carex curvula, the position of the dominants decreased significantly. The Festuca supina-communities undergo desintegration and replacement by other phytocoenoses with dominance Juniperus alpinа, Vaccinium myrtillus, V. vitis-idaea, V. uliginosum and Calamagrostis villosum. Over the last decade, radical changes have taken place in Carex curvula-communities. In contrast to the decisive influence of postpastoral demutation processes on the degradation of Festuca supina-communities, changes in the phytocoenoses of Carex curvula are prima­rily climatogenically caused. It is established that in the alpine zone Festuca supina-communities do not belong to the indigenous primary phytocoenoses, but are secondary pastorally conditioned derivative succession stages of primary communities of other associations. Rapid positive dynamics over the last ten years of such mesochionophilous species as Veronica alpina, Gnaphalium supinum, Soldanella hungarica, Luzula spadicea and, at the same time, negative changes in populations of obligate chionophiles Cerastium cerastoides and Saxifraga carpatica indicate transformation processes within the communities connected to the areas under long and deep snow cover. These processes indicate rapid successional changes under the influence of increa­sing vegetation period due to the reduction of the duration of snow cover in the territory of chionophilous phytocoenoses, which is due to modern climate changes, primarily warming.

Microfungal diversity of Juncus trifidus L. and Salix herbacea L. at isolated locations in the Sudetes and Carpathian Mountains

During cold periods in the Pleistocene Epoch, many plants known as the “relict species” migrated and inhabited new areas. Together with plants, some microfungi also migrated, remaining present on plants and in plant communities. However, the relationship between fungi and the migrating plants (especially host plants) is not well understood. Therefore, we examined the diversity and distribution of microfungi associated with two migratory relict plants in the Sudetes and Carpathian Mountains: <em>Salix herbacea</em> L. and <em>Juncus trifidus</em> L. In total, we found 17 taxa of fungi that were collected from nine different locations. Nine fungal taxa were collected on <em>S. herbacea</em>, and eight taxa on <em>J. trifidus</em>. Localities richest of fungi on <em>S. herbacea</em> were Mały Śnieżny Kocioł (Karkonosze Mts, Sudetes) and on <em>J. trifidus</em>, the Tatra Mts (Carpathian Mts). This work provides new insights into the distribution of fungi inhabiting <em>S. herbacea</em> and <em>J. trifidus</em> in Poland.

Changes in vitality of populations of rare arctic-alpine plant species in high mountain part of the Ukrainian Carpathians under the influence of climatic factors

Changes in vitality of populations of rare arctic-alpine plant species ( Anemone narcissiflora , Bartsia alpina , Saussurea alpina , Pedicularis oederi ) of the Ukrainian Carpathians in the highland habitats under the influence of climatic factors were analyzed. Population vitality was investigated according to individual diagnostic parameters – vitality of individuals, population vitality index, population quality index, and according to population parameters – density, total and effective quantity. It was established that during 2010–2018, the vitality of the Saussurea alpina population on the Shpyci Mount remained average. The uneven distribution of individuals on habitat area and complex spatial structure of the population loci positively affected the vitality of the Saussurea alpina population on Mt. Shpyci. Individuals of different vitality levels and heterogeneous structure according to morphometric parameters were observed in population. A decrease in population vitality and flowering gaps of generative individuals were observed in Saussurea alpina population on Mt. Petros due to climatic changes, intrapo­pulation processes, and anthropogenic stress. The upper locus of the only population of Pedicularis oederi in Ukraine between Brebeneskul and Munchel mountains underwent transformation, in particular, drying out of suitable habitats due to climate change. The population also underwent periodic anthropogenic influence as a result of grazing, which leads to unstable demographic trends – decrease in the habitat area, number of adults and generative individuals, coefficient of generative reproduction etc. A vitality of the Anemone narcissiflora population behind Nesamovyte Lake remains high. During 2011–2018, the total population size increased due to subsenile and senile individuals, while a number of the pregenerative individuals and the effective population size decreased. An increase in ontogenesis polyvariability, density of individuals, recovery index, number of pregenerative individuals and decrease in number of generative individuals are observed in Bartsia alpina population on Mt. Rebra due to overgrowth of the habitat by highdensity plants and shrub species ( Juncus trifidus , Vaccinium myrtillus and Rhododendron myrtifolium ). Clonal reproduction was intensified. Rejuvenation of populations and a increase in pregenerative phases duration, in particular – immature and virginile periods, were observed.

Синтаксономия луговин тундрового пояса гор Мурманской области

Синтаксономия луговин тундрового пояса гор Мурманской области

Aureobasidium pullulans from Juncus trifidus L. roots

Studies on endophytes of Juncus trifidus roots have been conducted. An analysis of isolated Aureobasidium pullulans strain is presented. Taxonomical data were confirmed by morphological and molecular data. Sequence of the ITS region has been determined and used for phylogenetic assesment.

Biogeographic relationships between fungi and selected glacial relict plants

The paper discusses fungi of 24 glacial relict plants: <em>Arenaria ciliata</em> L. subsp. <em>ciliata, Betula nana</em> L., <em>B. pubescens</em> Ehrh. subsp. carpatica (Willd.) Asch. & Graebn., <em>B. pubescens</em> subsp. <em>czerepanovii</em> (N.I. Orlova) Hämet-Ahti, <em>C. magellanica</em> Lam. subsp. <em>irrigua</em> (Wahlenb.) Hiitonen, <em>Carex rupestris</em> All., <em>Cerastium alpinum</em> L., <em>C. cerastoides</em> (L.) Britton, <em>C. eriophorum</em> Kit. in Schult., <em>Chamaedaphne calyculata</em> (L.) Moench, <em>Dryas drummondii</em> Richards, <em>D. grandis</em> Juz., <em>D. integrifolia</em> Vahl., <em>D. octopetala</em> L. s.l., <em>Empetrum hermaphroditum</em> Hagerup, <em>E. nigrum</em> L., <em>Juncus trifidus</em> L., <em>Loiseleuria procumbens</em> (L.) Desv., <em>Pedicularis sudetica</em> Willd., <em>Rubus chamaemorus</em> L., <em>Salix herbacea</em> L., <em>S. lapponum</em> L., <em>S. reticulata</em> L., and <em>Saxifraga nivalis</em> L., The work is attempt at application of some fungi (<em>Ascomycota, Chytridiales, Ustilaginales, Uredinales</em>, mitosporic fungi) as guides in vascular plant phytogeography and explanation of the origin of selected glacial relict plants. Parasites and exclusive (specialized) for particular host plant species are the most important fungi for biogeographic analysis. A fungal markers method (FMM) was used. The fungi and host plants for the present study were collected in the mountains and peat bogs of Poland, the Czech Republic, Lithuania, Slovakia, Sweden, Russia and Ukraine. Also materials from Austria, Canada, France, Greenland, Korea, Spitsbergen, Switzerland and U.S.A. were examined. A total of 254 taxa of fungi were collected from 1329 localities investigated. Exclusive species of fungi for all examined host plants have been distinguished. Only <em>Dryas octopetala</em> s.l., <em>D. integrifolia, Empetrum nigrum, E. hermaphroditum, Chamaedaphne calyculata</em> and <em>Rubus chamaemorus</em> possess a number of exclusive species sufficient for analysis. In some cases it was possible to define the direction of migration of the host plants (<em>Betula nana, Juncus trifidus, Dryas octopetala</em> s.l.) on the basis of mycological data. For dryads the extremely High Arctic track is more important than the Middle Arctic or Low Arctic ones. The waves of migrants moved from the East via Spitsbergen to-wards Greenland. <em>Dryas octopetala</em> seems to have reached the Carpathians from the West. Relative age of some fungi has been estimated. Wide circumpolar and alpine distribution points out that <em>Isothea rhytismoides</em> (Bab. ex Berk.) Fr. is one of the oldest dryadicolous fungi. The limited ranges of <em>Sphaerotheca volkartii</em> Blumer, <em>Synchytrium cupulatum</em> Thomas, <em>Hypoderma dryadis</em> Nannf.: L. Holm, and <em>Epipolaeum absconditum</em> (Johanson) L. Holm indicate a relatively young age of these species. A four new taxa i.e. <em>Lachnum uralense, Leptosphaentlina sibirica, Melanomma margaretae</em> and <em>Tiarospora pirozynskii</em> are described and illustrated. 27 species arę for the first time reported from Poland.

English

Bulgarian mountains are the southern distribution limit of several arctic-alpine species in Europe, many of them listed as threatened in the country. We assessed the diversity of arctic-alpine species in different mountain areas and selected the mountains with highest concentration of arctic-alpine species for field survey, sampling a total of 219 plots. The most frequently occurring species are Juncus trifidus, Poa alpina, Dryas octopetala, Bistorta vivipara, Omalotheca supina and Antennaria dioica. The frequency of these species increases with altitude and at northern aspect. Arctic-alpine plants take part in different vegetation classes, but are represented more frequently in Thlaspietea rotundifolii. The species tend to grow together, as a possible result of common functional characteristics and unified survival strategy. In 65% of sampled locations more than one target species were observed. Dianthus microlepis and Primula minima demonstrate very high association with the arctic-alpine species.

Some endophytes of Juncus trifidus from Tatra Mts. in Poland

This is a first part of work devoted highland rush endophytes: <em>Penicillium expansum, Cladosporium oxysporum, Arthrinium</em> state of <em>Apiospora montagnei</em> and <em>Aureobasidium pullulans</em>. The basidiomycete strain, possibly <em>Lagarobasidium detriticum</em> was also isolated.

Endophytic bacterial communities in three arctic plants from low arctic fell tundra are cold-adapted and host-plant specific

Endophytic bacteria inhabit internal plant tissues, and have been isolated from a large diversity of plants, where they form nonpathogenic relationships with their hosts. This study combines molecular and culture-dependent approaches to characterize endophytic bacterial communities of three arcto-alpine plant species (Oxyria digyna, Diapensia lapponica and Juncus trifidus) sampled in the low Arctic (69°03'N). Analyses of a 325 bacterial endophyte isolates, as well as seven clone libraries, revealed a high diversity. In particular, members of the Actinobacteria, Bacteroidetes, Firmicutes, Acidobacteria, and Proteobacteria were found. The compositions of the endophytic bacterial communities were dependent on host-plant species as well as on snow cover at sampling sites. Several bacterial genera were found to be associated tightly with specific host-plant species. In particular, Sphingomonas spp. were characteristic for D. lapponica and O. digyna, and their phylogenetic grouping corresponded to the host plant. Most of the endophyte isolates grew well and retained activity at +4 °C, and isolate as well as clone library sequences were often highly similar to sequences from bacteria from cold environments. Taken together, this study shows that arctic plants harbour a diverse community of bacterial endophytes, a portion of which seems to be tightly associated with specific plant species.

Floristic heterogeneity of Festuca airoides-dominated grasslands in the Romanian Carpathians

We numerically analysed 154 relevés of Potentillo chrysocraspedae–Festucetum airoidis in order to review the compositional variability of these grasslands, the main eco-floristic gradients and the representativeness of the lectotype. Apart from 30 small-sized clusters composed of singular or transitional relevés (outliers), three distinctive groups of 77, 19 and 12 communities were finally retained and denominated as typical (TP), closed (CL) and open (OP) facies, as they were significantly different in terms of total species cover. The three facies are well separated but do not form distinctive clusters in the non-metric multidimensional scaling (NMDS) ordination space. Juncus trifidus and Agrostis rupestris are the best differential species of OP and TP, respectively, whereas the best discriminator of CL is the higher cover of F. airoides. There are no significant differences between the three facies regarding altitude. The floristic structure of CL indicates poorer but moister soils compared with the other facies. CL may represent either a post-disturbance, recovery phase following sheep overgrazing and intensive trampling, or a late seral stage. OP gathers communities that are little disturbed and mainly occur on ridges and upper, sunny slopes. Although well distinguished floristically, TP is weakly defined in terms of homotoneity and complexity of the core species assemblage. The most representative relevé of TP is poorer in character species than the relevé lectotype (5 versus 12), the latter being classified as an outlier in terms of normal specific assemblage. Such patterns may reflect the spatio-temporal heterogeneity in alpine grasslands due to uncontrolled, intensive grazing and stochastic natural disturbances.

Diderma alpinum . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Diderma alpinum , a nivicolous myxomycete (slime mould). Some information on its dispersal and transmission and conservation status is given, along with details of its geographical distribution (Morocco, USA (Alaska, California, Colorado, Montana, Utah, Virginia, Washington), Brazil, Macquarie Island, India, Japan, Nepal, Uzbekistan, Australia (Tasmania and Victoria), New Zealand, Austria, Finland, France, Germany, Greece, Italy, Poland, Russia (Moscow oblast), Slovenia, Spain, Switzerland, UK, and Ukraine), hosts ( Alnus viridis , Deschampsia alpina , D. cespitosa , Empetrum nigrum , Juncus trifidus , Larix sp., Nardus stricta , Plantae indet., Rubus sp., and Vaccinium myrtillus ), and interactions and habitats.

Lepidoderma carestianum . [Descriptions of Fungi and Bacteria

Abstract A description is provided for Lepidoderma carestianum , a nivicolous myxomycete. Some information on its dispersal and transmission and conservation status is given, along with details of its geographical distribution (Canada (Ontario), USA (Arizona, California, Colorado, Iowa, Kansas, Massachusetts, Michigan, New Hampshire, New Mexico, Washington), Japan, Russia (Chukotskyi Avtonomnyi okrug), Australia (New South Wales), New Zealand, Austria, Denmark, France, Italy, Norway, Poland, Russia (Leningradskaya oblast), Slovenia, Spain, Sweden, Switzerland, UK, and Ukraine), hosts ( Deschampsia cespitosa , Empetrum nigrum subsp. hermaphroditum , Graminae indet., Juncus trifidus , Nardus stricta , Plantae indet., Rubus idaeus , Sasa kurilensis , Taxus sp., Vaccinium myrtillus ), other substrata (soil), interactions and habitats.

Vegetation structure and aboveground biomass at Mount Salatín long-term ecological research site, the West Tatra Mts, Slovakia

Halada Ľ., David S., Halabuk A.: Vegetation structure and aboveground biomass at Mount Salatin long-term ecological research site, the West Tatra Mts, Slovakia. Ekologia (Bratislava), Vol. 28, No. 2, p. 113–126, 2009. A detailed characteristic of vegetation in the long-term ecological research site using quantitative methods is provided. Plant species composition, frequencies and aboveground biomass of 25 research plots are reported. Additionally, inter-species relations and spatial pattern of vegetation are analysed. Plant community at Mt. Salatin research site belongs to the association Juncetum trifidi S z a f e r et al. 1923 em. K r a j i n a 1933 (alliance Juncion trifidi K r a j i n a 1933). Main dominants are represented by Oreochloa disticha, Festuca supina and Cetraria islandica, that are evenly distributed throughout the plots with mean frequencies of 39%, 38% and 57% respectively. Significant correlations have been detected between several species what might imply their competition or coexistence. The mean aboveground biomass of vascular plants at Mt. Salatin was estimated to 109.4 g.m -2 . At plot level, grasses (91.02 g.m -2 ) and Juncus trifidus (32.52 g.m -2 ) account for substantial proportion of the biomass. Values of constancy, frequencies and biomass amount together with an analysis of the spatial pattern contribute to a complex understanding of the vegetation structure at Mt. Salatin research site.

Ice Propagation in Dehardened Alpine Plant Species Studied by Infrared Differential Thermal Analysis (IDTA)

Infrared differential thermal analysis (IDTA) was used to study ice propagation and whole plant freezing patterns in dehardened intact individuals of various alpine plant species, including a shrub (Rhododendron ferrugineum), a herbaceous plant (Senecio incanus), a cushion plant (Silene acaulis), and two graminoids (Poa alpina and Juncus trifidus). Freezing patterns differed markedly among species and reflected peculiarities of the shoot structure and the vascular system. In graminoids, each single leaf required a separate ice nucleation event, as the polystele prevents ice propagation between leaves via the stem. Additionally, enhanced supercooling resulted in a temperature range of whole plant freezing of up to 10°C, which corroborates the high summer frost resistance of graminoids. This could have ecological significance for frost survival. In contrast, in dicotyledonous species one nucleation event was usually sufficient for whole plant freezing. Controlled ice-seeding experiments on leaves with droplets of water and bacterial water suspension (Pseudomonas syringae) showed that ice propagation into the leaf tissue from the surface was inhibited as long as the leaves were undamaged. The rate of ice propagation in veins was significantly higher at lower temperatures and reached up to 24 cm s−1 in J. trifidus, which is much higher than reported in earlier findings. Ice propagation in graminoids was much faster, which may indicate that ice propagates within the protoxylem lacunae of large vessels.

Reindeer Winter Grazing in Alpine Tundra: Impacts on Ridge Community Composition in Norway

ABSTRACTWe analyzed lichen species composition and biomass in 815 plots on 163 sites across wild reindeer regions in Norway, ranging from ranges with a long history of very low grazing pressure to heavily grazed sites. Reindeer density (1974–2000) and lichen biomass were well correlated for sites with comparable snow cover, altitude and terrain (R 2 = 0.81, P = 0.006, n = 12). Absence of grazing for potentially several centuries has virtually resulted in a monoculture consisting of Cladina stellaris, Flavocetraria nivalis, and Alectoria ochroleuca (Syn. Bryocaulon ochroleuca). Light grazing in terms of 20 to 30% removal of initial lichen cover easily eroded Cladina stellaris from exposed ridges by cratering and trampling by reindeer through the snow, while Flavocetraria nivalis persisted longer. This decline in lichen cover observed along a historic grazing gradient further resulted in increasing cover of bare ground, but less than expected from lichen removal due to gradual colonization of other species, such as mosses (incl. Polytrichum piliferum), crustose and fruticose lichens, dwarf shrubs (Arctostaphylos spp., Empetrum nigrum, Loiseleuria procumbens), and graminoids, particularly rushes (Juncus trifidus). Moderate grazing may thus increase plant diversity on ridges compared to ungrazed lands, and hence strongly influence gradients in biomass, composition and abundance of ridge communities across the landscape.

Phylogenetic relationships within Luzula DC. and Juncus L. (Juncaceae): A comparison of phylogenetic signals of trnL-trnF intergenic spacer, trnL intron and rbcL plastome sequence data.

Juncus and Luzula are the largest, almost cosmopolitan, genera in the Juncaceae. Relationships within Juncus and Luzula and among other genera of Juncaceae (Distichia, Marsippospermum, Oxychloë, Patosia and Rostkovia) remain incompletely resolved. RbcL sequence data resolved a part of the supraspecific phylogeny, but many clades remain polytomic. For this reason, the non-coding cpDNA regions, trnL intron and trnL-trnF intergenic spacer, were sequenced. We intended to create hypotheses of relationships within Juncaceae and to test the classification of the sections, but a primary goal to this study was to assess the relationships within Juncus and Luzula and to test for monophyly of groups recognized from rbcL data (especially the monophyly of genus Luzula and the Southern Hemisphere Clade (SHC)). Furthermore, we tested the influence of different rooting and ingroup composition on the tree topology. The parsimony analyses revealed several well-supported lineages. The traditionally distinguished genus Luzula is monophyletic and Juncus is non-monophyletic. Two subgenera of Luzula (Pterodes and Luzula) are non-monophyletic, while subg. Marlenia forms a sister group to the whole Luzula clade (trnL-F data set). Within Juncus, both subgenus Juncus and subgenus Agathryon are non-monophyletic. SHC is clustered not only with the South African J. lomatophylus and J. capensis, but also together with members of the section Juncus, Caespitosi and Graminifolii. These sections form a well-separated sister group to the SHC. Within the genera Juncus and Luzula, monophyly is demonstrated for a number of groups (e.g., Juncus section Stygiopsis, Luzula section Luzula) but questioned for others (e.g., Juncus section Graminifolii). The unusual, separate positioning of Juncus trifidus and J. monanthos were clarified by trnL-trnF sequence data, but vary within the tree topology depending on outgroup selection and also due to LBA phenomenon.

Phylogenetic Relationships in the Juncaceae Inferred from Nuclear Ribosomal DNA Internal Transcribed Spacer Sequence Data

The Juncaceae includes seven genera and ca. 440 species and is cosmopolitan in distribution. The bulk of the species diversity is found in Juncus (315 species) and Luzula (115 species). Here I present a phylogenetic study within Juncaceae that focuses on the large genus Juncus, using maximum parsimony, maximum likelihood, and Bayesian inference phylogenetic analyses of the nuclear ribosomal DNA internal transcribed spacer region (ITS), and samples the genera Distichia, Juncus, Luzula, and Oxychloe. The ITS data support the placement of Oxychloe with the other cushion plant genus Distichia well within the family, contrary to the placement as sister to the Cyperaceae in previous studies. Juncus is paraphyletic, with all of the other sampled Juncaceae genera nested within it. Luzula appears related to Juncus capitatus and Juncus trifidus, while the two cushion plant genera, Distichia and Oxychloe, are sister taxa and are nested within a clade of Juncus species from Juncus subgenus Juncus sections Juncotypus ...