Pteridium Research Articles

Over and understory controls on red pine establishment and seedling survival in the largest remaining old-growth red pine forest

The ecological constraints on red pine (Pinus resinosa Ait.) regeneration in multi-cohort stands are not fully understood given the species’ long history of even-aged management. In this study a structural equation modelling approach is used to dissect the biotic and abiotic controls on seedling establishment and survival in North America’s largest remaining multi-cohort red pine forest. We characterized the under and overstory vegetation as well the soil and litter layer surrounding Wolf Lake in the Wolf Lake Forest Reserve (approx. 1600ha), Sudbury, ON. The understory of this pine dominated stand was found to be characterized by a feather moss-ericaceous community. Red pine establishment was primarily determined by favourable seed bed conditions, namely limited depth of the litter layer, and to some degree by light availability. Additionally, overstory species composition determined establishment of red pine and other shrub species, likely through distinct contributions to the litter layer. Our model suggests that red pine seedlings compete both in the shaded understory and in well-lit plots. We suspect that the northward migrating species, red maple (Acer rubrum) and white pine (Pinus strobus), exert strong competitive effects especially in canopy gaps. Given that uneven-aged management systems are likely to promote establishment of the competing species, red maple, paper birch (Betula papyrifera) and bracken fern (Pteridium aquilinum var. latiusculum), we suggest successful red pine regeneration is unlikely under these systems.

Dissipation of pterosin B in acid soils – Tracking the fate of the bracken fern carcinogen ptaquiloside

Bracken ferns (Pteridium spp.) are well-known for their carcinogenic properties, which are ascribed to the content of ptaquiloside and ptaquiloside-like substances. Ptaquiloside leach from the ferns and may cause contamination of drinking water. Pterosin B is formed by hydrolysis of ptaquiloside. In soil, Pterosin B is adsorbed more strongly and it is expected to have a slower turnover than ptaquiloside. We thus hypothesized that pterosin B may serve as an indicator for any past presence of ptaquiloside. Pterosin B degradation was studied in acid forest soils from bracken-covered and bracken-free areas. Soil samples were incubated with pterosin B at 3 and 8 μg g−1 for 10 days, whereas sterile (autoclaved) samples were incubated for 23 days. Pterosin B showed unexpected fast degradation in soils with full degradation in topsoils in 2–5 days. Pterosin B dissipation followed the sum of two-first order reactions. The initial fast reaction with half-lives of 0.7–3.5 h contributed 11–59% of the total pterosin B degradation, while the slow reaction was 20–100 times slower than the fast reaction. Total dissipation half-lives were shorter for loamy sand (4 h) than for sandy loam soils (28 h). No degradation of pterosin B took place under sterile conditions assuming observed dissipation during the first 3 h could be attributed to irreversible sorption. Our results demonstrate that pterosin B is microbially degraded and that pterosin B is as unstable as ptaquiloside and hence cannot be used as an indicator for former presence of ptaquiloside in soil.

Evaluation of the epidemiological bovine enzootic haematuria associated with prevalence of bracken fern in Paraná state

The Bovine Enzootic Haematuria is a disease resulting from bracken fern intake, affecting animals in almost all states of Brazil. Due to economic losses and the risk to public health, research continues looking for ways to control plant and illness, as there are still places where cattle are created in direct contact with the plant, mainly in the state of Parana. In another perspective, many field workers engaged in awareness among farmers that continue to challenge the science, believing enzootic haematuriahas no direct relationship with the bracken fern. They suggest other etiologies, argue homemade prophylaxis and live therapeutic empiricism. Meanwhile, this plant is still present in several municipalities and the manifestation of characteristic and peculiar hemorrhagic in cattle grows visibly. This situation is very present in places occupied by cattle where the topography is quite rugged, with no possibility of land mechanization. Allied to this, there is evident lack of government policy in providing subsidiary liming the soil to correct the acidity caused by excess aluminum. Thus exposed, in a comprehensive study on municipal districts, bracken fern holders in their pastures, the authors correlated the existence of the plant to natural manifestation of Bovine Enzootic Haematuria for, a future and timing, get sensitize farmers to control plant, the disease elimination and increased safety public health, consumer of animal by-products such as meat and milk

Factors limiting montane forest regeneration in bracken-dominated habitats in the tropics

Tropical montane forests are threatened by human-induced fires, resulting in forest patches surrounded by disturbed habitats frequently dominated by bracken fern (Pteridium spp.). In most disturbed habitats, natural forest regeneration is principally hindered by (i) seed limitation, due to a lack of seed dispersal, and (ii) establishment limitation, due to harsh abiotic conditions or competition with grasses and weeds. To our knowledge, the combined effect of seed limitation and establishment limitation on the entire regenerating plant community has never been tested in tropical bracken-dominated habitats. We experimentally assessed the effect of bracken fronds on natural seedling establishment in different distances from a tropical montane forest of the Bolivian Andes. At ten sites, we placed 240m-long transects ranging from the forest interior to the disturbed habitat and installed paired plots at seven distances along each transect. In one plot of each pair, we applied a repeated vegetation removal treatment to assess the effect of bracken fronds on seedling establishment. We analysed the effect of bracken removal on seedling richness, seedling survival and growth of tree and non-tree species. We additionally compared patterns in seedling density and richness from the forest interior towards the disturbed habitat with patterns in seed density and richness in the seed rain and the soil seed bank. Species richness was higher in the forest than in the disturbed habitat. Tree species corresponded to approx. 25% of the species pool in the disturbed habitat and were only present at low densities. Density and species richness of seeds and tree seedlings consistently decreased from the forest edge towards the disturbed habitat, suggesting seed limitation. Seedlings of tree species had high survival probabilities in the disturbed habitat, especially under bracken fronds, suggesting a lack of establishment limitation. Bracken removal in the disturbed habitat did not affect species richness, but significantly reduced seedling survival and growth of tree and non-tree species. Our results suggest that low seed dispersal hinders natural regeneration of bracken-dominated habitats in the tropics and that bracken fronds do not impede seedling establishment. Seed addition of tree species into the bracken vegetation may therefore be a promising strategy to accelerate forest regeneration, but long-term studies and multispecies experiments are needed for assessing the success of this restoration strategy.

Ptaquiloside from bracken in stream water at base flow and during storm events

The bracken fern (Pteridium spp.) densely populates both open and woodland vegetation types around the globe. Bracken is toxic to livestock when consumed, and a group of potent illudane-type carcinogens have been identified, of which the compound ptaquiloside (PTA) is the most abundant. The highly water soluble PTA has been shown to be leachable from bracken fronds, and present in the soil and water below bracken stands. This has raised concerns over whether the compound might pose a risk to drinking water sources.We investigated PTA concentrations in a small stream draining a bracken-infested catchment at base flow and in response to storm events during a growth season, and included sampling of the bracken canopy throughfall. Streams in other bracken-dominated areas were also sampled at base flow for comparison, and a controlled pulse experiment was conducted in the field to study the in-stream dynamics of PTA.Ptaquiloside concentrations in the stream never exceeded 61 ng L−1 in the base flow samples, but peaked at 2.2 μg L−1 during the studied storm events. The mass of PTA in the stream, per storm event, was 7.5–93 mg from this catchment. A clear temporal connection was observed between rainfall and PTA concentration in the stream, with a reproducible time lag of approx. 1 h from onset of rain to elevated concentrations, and returning rather quickly (about 2 h) to base flow concentration levels.The concentration of PTA behaved similar to an inert tracer (Cl−) in the pulse experiment over a relative short time scale (minutes-hours) reflecting no PTA sorption, and dispersion and dilution considerably lowered the observed PTA concentrations downstream.Bracken throughfall revealed a potent and lasting source of PTA during rainfall, with concentrations up to 169 μg L−1, that did not decrease over the course of the event. In the stream, the throughfall contribution to PTA cannot be separated from a possible below-ground input from litter, rhizomes and soil. Catchment-specific factors such as the soil pH, topography, hydrology, and bracken coverage will evidently affect the level of PTA observed in the receiving stream, as well as the distance from bracken, but time since precipitation seems most important.Studying PTA loads and transport in surface streams fed by bracken-infested catchments, simply taking occasional grab samples will not capture the precipitation-linked pulses. The place and time of sampling governs the findings, and including event-based sampling is essential to provide a more complete picture of PTA loads to surface water.

Allelopathy of Bracken Fern (Pteridium arachnoideum): New Evidence from Green Fronds, Litter, and Soil.

The neotropical bracken fern Pteridium arachnoideum (Kaulf.) Maxon. (Dennstaedtiaceae) is described as an aggressive pioneer plant species. It invades abandoned or newly burned areas and represents a management challenge at these invaded sites. Native to the Atlantic Forest and Cerrado (Tropical Savanna) Brazilian biomes, P. arachnoideum has nevertheless become very problematic in these conservation hotspots. Despite some reports suggesting a possible role of allelopathy in this plant’s dominance, until now there has been little evidence of isolated and individually identified compounds with phytotoxic activities present in its tissues or in the surrounding environment. Thus, the aim of this study was to investigate the allelopathic potential of P. arachnoideum by isolating and identifying any secondary metabolites with phytotoxic activity in its tissues, litter, and soil. Bioguided phytochemical investigation led to the isolation and identification of the proanthocyanidin selligueain A as the major secondary compound in the green fronds and litter of this fern. It is produced by P. arachnoideum in its green fronds, remains unaltered during the senescence process, and is the major secondary compound present in litter. Selligueain A showed phytotoxic activity against the selected target species sesame (Sesamum indicum) early development. In particular, the compound inhibited root and stem growth, and root metaxylem cell size but did not affect chlorophyll content. This compound can be considered as an allelochemical because it is present in the soil under P. arachnoideum patches as one of the major compounds in the soil solution. This is the first report of the presence of selligueain A in any member of the Dennstaedtiaceae family and the first time an isolated and identified allelochemical produced by members of the Pteridium species complex has been described. This evidence of selligueain A as a putative allelochemical of P. arachnoideum reinforces the role of allelopathy in the dominance processes of this plant in the areas where it occurs.

Haemolymph Defense Capacity of the Neotropical sawfly Aneugmenus merida against Ant Predation

The defensive characteristics of the sawflies have received special attention due to the involvement of toxic compounds obtained from host plants. In this context, the haemolymph-based defense is one of the strategies known in sawflies to dissuade the attack of predators. Aneugmenus merida is a neotropical sawfly whose larvae are herbivorous on the toxic bracken fern Pteridium spp. The present study examines the defensive properties of the A. merida larval haemolymph and its possible link with the chemistry of its host plant. We report the behavior of the solitary hunter ant Odontomachus chelifer towards A. merida larvae under laboratory conditions. In addition, we studied the liquid intake behavior of the ants provided with solutions of crude haemolymph, bracken extracts, and its fractions. A. merida larvae showed a marked defensive capacity against the ants. The inhibition of the attack was observed during the stages of antennal contact and mandibular blow, suggesting that larval defensive capacity is due to factors present in the integument and haemolymph. Aqueous and methanolic fractions of haemolymph and bracken also deterred feeding. Although some common compounds were detected in the haemolymph and bracken fractions, they were in very small quantities, suggesting that they are not responsible for the bioactivity. Therefore, the hypothetical connection between the host plant chemistry and larval defensive capacity could not be evidenced. We suggest that the deterrent compounds present in the haemolymph and integument could be jointly acting in the sawfly’s defensive strategy.

Hematological, biochemical and urinalysis evaluations in different categories of females Nellore from farms with and without the presence of bracken fern (Pteridium arachnoideum) in pastures

The Pteridium arachnoideum, previously classified as Pteridium aquilinum, popularly known as bracken fern, is one of the most preoccupying poisonous vegetables in several countries, including Brazil. Brazilian researchers characterized, experimentally, three clinic forms of diseases caused by bracken fern to cattle: bleeding diathesis, bovine enzootic hematuria and squamous cell carcinoma in the upper digestive tracts. In the present work were studied the hematological, biochemical and urinalysis values of three different phases of the animal development: 56 calves, 58 heifers and 55 cows from farms with similar zootechnical characteristics and with and without the presence of bracken fern. From results there was a significant fall in the values of the globular volume, hemoglobin and number of red blood cells in the calves from farms with the presence of bracken fern. However, for the group of cows and heifers there was a fall only in the number of red blood cells, compared to the group of animals from farms without the presence of bracken fern. The number of platelets was significantly superior in all of the age groups of animals from farms with bracken fern. There were no significant alterations in the leucocyte count, in both groups, indicating that there was no systemic inflammatory response in any of the three categories.

Propagation by partial tissue culture of Austral Bracken (Pteridium esculentum) for revegetation

SummaryAustral Bracken (Pteridium esculentum) is a native fern common in many Australian ecosystems and is needed in large numbers for revegetation projects. The main limiting factor for the propagation of locally sourced material is spore availability. A mass propagation system was developed by combining tissue culture and nursery‐based systems. Spores collected over the summer months from wild populations were germinated in vitro on ½ MS medium containing 0.15% w/v activated charcoal. Gametophytes were rapidly multiplied on the same medium. In vitro sporophyte development was unreliable although sometimes prolific. However, gametophytes transferred to a pine bark potting medium with added coir, on a capillary bed in a fog house, produced sporophytes reliably. Across different seasons and populations, 75–100% of the gametophyte explants developed sporophytes within about 9 weeks. Three hundred propagated ferns planted into two field sites within their provenance origins had a survival of 92 and 95% respectively, 3 or 4 months after planting. This report delivers a ready‐to‐use and reliable protocol for the mass propagation of bracken fern of local origin to the revegetation industry.

Ptaquiloside in Irish Bracken Ferns and Receiving Waters, with Implications for Land Managers.

Ptaquiloside, along with other natural phytotoxins, is receiving increased attention from scientists and land use managers. There is an urgent need to increase empirical evidence to understand the scale of phytotoxin mobilisation and potential to enter into the environment. In this study the risk of ptaquiloside to drinking water was assessed by quantifying ptaquiloside in the receiving waters at three drinking water abstraction sites across Ireland and in bracken fronds surrounding the abstraction sites. We also investigated the impact of different management regimes (spraying, cutting and rolling) on ptaquiloside concentrations at plot-scale in six locations in Northern Ireland, UK. Ptaquiloside concentrations were determined using recent advances in the use of LC-MS for the detection and quantification of ptaquiloside. The results indicate that ptaquiloside is present in bracken stands surrounding drinking water abstractions in Ireland, and ptaquiloside concentrations were also observed in the receiving waters. Furthermore, spraying was found to be the most effective bracken management regime observed in terms of reducing ptaquiloside load. Increased awareness is vital on the implications of managing land with extensive bracken stands.

ERas protein is overexpressed and binds to the activated platelet-derived growth factor β receptor in bovine urothelial tumour cells associated with papillomavirus infection

Embryonic stem cell-expressed Ras (ERas) encodes a constitutively active form of guanosine triphosphatase (GTPase) that binds to and activates phosphatidylinositol 3 kinase (PI3K), which in turn phosphorylates and activates downstream targets such as Akt. The current study evaluated ERas regulation and expression in papillomavirus-associated urothelial tumours in cattle grazing on lands rich in bracken fern. ERas was found upregulated and overexpressed by PCR, real time PCR and Western blot. Furthermore, protein overexpression was also confirmed by immunohistochemistry. ERas was found to interact physically and colocalise with the activated platelet derived growth factor β receptor (PDGFβR) by coimmunoprecipitation and laser scanning confocal investigations. Phosphorylation of Akt, a downstream effector both of ERas and PDGFβR, appeared to be increased in urothelial tumour cells. Altogether, these data indicate that ERas/PDGFβR complex could play a role in the pathogenesis of bovine papillomavirus-associated bladder neoplasia.

Epidemiological study on the prevalence of Bovine Enzootic Haematuria associated with bracken fern presence in Paraná State, Brazil

Epidemiological study on the prevalence of Bovine Enzootic Haematuria associated with bracken fern presence in Paraná State, Brazil

Epidemiological study on the prevalence of Bovine Enzootic Haematuria associated with bracken fern presence in Paraná State, Brazil

Epidemiological study on the prevalence of Bovine Enzootic Haematuria associated with bracken fern presence in Paraná State, Brazil

Human gastric cancer, Helicobacter pylori and bracken carcinogens: A connecting hypothesis

Long term infection of Helicobacter pylori (Hp) virulent strains is a key factor in the genesis of human gastric cancer, and so are certain dietary proinflammatory and genotoxic compounds. Carcinogenic bracken fern (Pteridium spp.) is one of these. Toxins from this plant are consumed as bracken culinary preparations, through milk and meat of bracken-exposed livestock, and drain waters from bracken swards. Bracken toxin ptaquiloside (PtQ), a suspected human carcinogen, elicits complex responses in animals leading to death. PtQ and Hp might cooperate in gastric pathologies. This paper presents an hypothesis on PtQ–Hp association leading to the enhancement of carcinogenesis in the human gastric environment that might explain the high gastric cancer incidence and death rates among Hp-infected people living in bracken zones at two levels: (1) The macroscopic scale comprising the flow of PtQ in the human diet. (2) the microscopic scale encompassing (A) gastric luminal medium; (B) gastric mucus structure and mucin degradation elicited by Hp; (C) bacterial pH gradient modification of the gastric mucosa that favors PtQ survival and its penetration into epithelial tissue; (D) combined PtQ/Hp effects on gastric immune and inflammatory responses; (E) PtQ–Hp complementary activity at selected cell signaling cascades and genome disturbance.

Origins and diversity of a cosmopolitan fern genus on an island archipelago.

Isolated oceanic islands are characterized by patterns of biological diversity different from that on nearby continental mainlands. Isolation can provide the opportunity for evolutionary divergence, but also set the stage for hybridization between related taxa arriving from different sources. Ferns disperse by haploid spores, which are produced in large numbers and can travel long distances in air currents, enabling these plants to become established on most oceanic islands. Here, we examine the origins and patterns of diversity of the cosmopolitan fern genus Pteridium (Dennstaedtiaceae; bracken) on the Galapagos Islands. We use nucleotide sequences from two plastid genes, and two nuclear gene markers, to examine phylogeography of Pteridium on the Galapagos Islands. We incorporate data from a previous study to provide a worldwide context. We also sampled new specimens from South and Central America. We used flow cytometry to estimate genome size of some accessions. We found that both plastid and nuclear haplotypes fall into two distinct clades, consistent with a two-diploid-species taxonomy of P. aquilinum and P. esculentum. As predicted, the allotetraploid P. caudatum possesses nuclear haplotypes from both diploid species. Samples from the Galapagos include P. esculentum subsp. arachnoideum, P. caudatum and possible hybrids between them. Multiple Pteridium taxa were also observed growing together at some sites. We find evidence for multiple origins of Pteridium on the Galapagos Islands and multiple origins of tetraploid P. caudatum throughout its range in Central and South America. We also posit that P. caudatum may include recent diploid hybrids, backcrosses to P. esculentum, as well as allotetraploid plants. The Galapagos Islands are positioned close to the equator where they can receive dispersing propagules from both hemispheres. This may partly explain the high levels of diversity found for this cosmopolitan fern on these islands.

Looking Back for the Future: Local Knowledge and Palaeoecology Inform Biocultural Restoration of Coastal Ecosystems in New Zealand

We combine local knowledge of elders and environmental practitioners from two indigenous Māori communities and pollen evidence in soil cores from two islands and two mainland coastal sites to inform the planning of coastal ecosystem restoration initiatives in New Zealand. The Māori participants desired ecosystems that delivered cultural (e.g., support for identity), social (e.g., knowledge transfer), economic (e.g., agroecology) and environmental (e.g., biodiversity protection) outcomes to their communities. Pollen records identified three periods when vegetation was dominated by different taxa: (1) Pre-human (<AD c.1280) – forest dominated by native conifers, angiosperms and nīkau palm (Rhopalostylis sapida); (2) Māori settlement (AD c.1280–1770) – scrub and bracken fern (Pteridium esculentum); and (3) European settlement (post-1770) – Metrosideros excelsa forest with harakeke (Phormium sp.), raupō (Typha orientalis), grasses (Poaceae), exotic plantation conifers (Pinaceae), and agricultural weeds. A fourth, aspirational system that integrated human activities such as agriculture and horticulture with native forest was conceptualized. Our approach emphasizes the importance of placing humans within nature and the reciprocity of environmental and social well-being.

Structure and Development of the Lateral-Line Aerenchyma in Bracken Ferns (Pteridium: Dennstaedtiaceae)

Premise of research. Bracken ferns have a worldwide distribution. Plants consist of aerial fronds with petioles (stipes) that extend underground to specialized subterranean stems (rhizomes). A narrow continuous surface strip of specialized aerenchyma on each side of rhizomes and stipes, referred to as the lateral line, forms a pathway for gases. Developmental changes in the lateral line appear to affect gas exchange and influence water relations, soil exploitation, dormant survival, and disease resistance in these plants. An integrated account of the ontogeny and cytochemistry of the lateral line in the rhizomes and stipes of Pteridium has not been published.Methodology. LM with fluorescence cytochemistry, supported by SEM, was used to compare developmental changes in tissues of the lateral-line aerenchyma in the stipes (petioles) and rhizomes (stems) of representative bracken taxa.Pivotal results. The lateral lines of the rhizome and stipe in Pteridium aquilinum and Pteridium esculentum are a continuous ...

Participatory Restoration of Degraded Agricultural Areas Invaded by Bracken Fern (Pteridium aquilinum) and Conservation in the Chinantla Region, Oaxaca, Mexico

Invasions of bracken fern, Pteridium aquilinum, are an important source of agricultural degradation in many tropical areas. We present a case study of apparent historical degradation of agricultural land which, combined with recent conservation measures, may have created new pressures on food production. Our study of two communities in the Chinantla region, Oaxaca, Mexico is based on interviews and documentation of low farmer awareness of the anthropogenic origins of bracken fern invasions, local knowledge of control techniques and the social-ecological implications of bracken degraded areas. A model for a potential participatory restoration project based on ongoing collective action processes in the communities is proposed. Financial support is needed to incentivize farmers to participate in restoration efforts, to recover productive lands and improve local livelihoods. Agricultural restoration efforts would contribute to sustainable multifunctional landscapes.

Natural Regeneration after Long-Term Bracken Fern Control with Balsa (Ochroma pyramidale) in the Neotropics

In many parts of the Neotropics, deforested areas are often colonized by the highly competitive invasive bracken fern (Pteridium aquilinum), which inhabits naturally regenerated forests and successional forests on abandoned farmland. Within the tropical forest region of Chiapas in southern Mexico, we implemented an experiment in 2005 to out-compete bracken fern infestation and reduce or eliminate live bracken rhizomes using several treatments: Direct sowing of balsa seeds (Ochroma pyramidale; Malvaceae), a traditional Lacandon treatment of scattering balsa seeds, transplanting balsa seedlings, and a control treatment (without balsa). For each treatment, we applied three different bracken weeding frequencies: No weeding, biweekly weeding, and monthly weeding. In this study, we present data gathered four years after establishing the experiment regarding: Bracken fern rhizome biomass, balsa density, basal area, height, density, species richness of naturally regenerating vegetation for all treatments, and bracken weeding frequencies. We also evaluated the importance of balsa and its regenerative attributes in controlling bracken fern by correlating it with remaining belowground live rhizome biomass. Living rhizome biomass was completely eradicated in all treatments with biweekly and monthly weeding. Density and species richness of a naturally regenerated species were negatively correlated with bracken fern rhizome biomass, and the density of this species was highest in areas with no rhizome biomass. Although balsa tree stands are effective short-term solutions for controlling rhizome biomass, the success of natural regeneration following balsa establishment can be critical to long-term elimination of bracken fern.

Особливості похідних березових молодняків у низькогір’ї Покуття (Українські Карпати)

Лісові ландшафти місцевого низькогір’я протягом останніх 3–5 століть зазнали глибокої антропогенної трансформації. Похідні молодняки тут займають до 25% загальної площі лісів. Проблема розвитку похідних деревостанів особливо актуальна для сучасної лісової типології в карпатському регіоні. Потребує відображення у типології динамічних тенденцій формування деревостанів, особливо змішаних молодняків. Мета нашого дослідження – пізнання структурних особливостей фітоценозів похідних березових молодняків у цьому районі. Об’єкт дослідження – молодняки I класу віку, що ростуть у басейні р. Лючка. Концептуальною основою нашого дослідження послужило сучасне динамічне розуміння типу лісу як послідовної серії лісових рослинних угруповань у межах однорідних умов місць росту. Застосовано методи еколого-флористичних досліджень школи Браун-Бланке в інтерпретації польської школи фітосоціології. У той же час до уваги брали синтаксономічні узагальнення українських учених. Фактичний матеріал – власні геоботанічні дослідження з фіксацією в рослинних угрупованнях переважної більшості видів. Обробляючи матеріал, головним чином до уваги брали види, що мають діагностичне значення для виділення синтаксонів рослинних угруповань. Молоді деревостани висотою 8–12 м та зімкненістю крон 70% формують спільно дерева Betula pendula и B. pubescens. Досить чисельну домішку утворюють дерева Alnus incana, а також трапляються Fagus sylvatica, Populus tremula, Quercus robur, Padus avium. За домінантами такі фітоценози можна назвати сіровільховими березняками ожиново-осоково-орляковими – Betula pendula+Alnus incana–Rubus caesius–Carex brizoides+Pteridium aquilinum. Це багаті у флористичному відношенні рослинні угруповання. Вони містять щонайменше 12 деревних видів, 3 – чагарників, 4 – чагарничків та 89 – трав’янистих видів. Діагностичні види свідчать про приналежність таких угруповань до класу середньоєвропейських листяних лісів Querco-Fagetea. Водночас є підстави вважати їх близькими до атлантичних кислих оліготрофних і мезотрофних листяних лісів класу Quercetea robori-petraeae. Однак 12 діагностичних видів підтверджують належність цих угруповань до порядку Fagetalia sylvaticae, який представляє європейські мезофітні широколисті ліси. На рівні союзів рослинних угруповань чіткої асоційованості не виявлено. Більшість діагностичних видів досліджених фітоценозів свідчить про близькість флористичної композиції до угруповань асоціації Potentillo albae-Quercetum, яка представляє світлі субконтинентальні діброви.