Rumex Acetosella Research Articles

Hair Fescue and Sheep Sorrel Identification Using Deep Learning in Wild Blueberry Production

Deep learning convolutional neural networks (CNNs) are an emerging technology that provide an opportunity to increase agricultural efficiency through remote sensing and automatic inferencing of field conditions. This paper examined the novel use of CNNs to identify two weeds, hair fescue and sheep sorrel, in images of wild blueberry fields. Commercial herbicide sprayers provide a uniform application of agrochemicals to manage patches of these weeds. Three object-detection and three image-classification CNNs were trained to identify hair fescue and sheep sorrel using images from 58 wild blueberry fields. The CNNs were trained using 1280x720 images and were tested at four different internal resolutions. The CNNs were retrained with progressively smaller training datasets ranging from 3780 to 472 images to determine the effect of dataset size on accuracy. YOLOv3-Tiny was the best object-detection CNN, detecting at least one target weed per image with F1-scores of 0.97 for hair fescue and 0.90 for sheep sorrel at 1280 × 736 resolution. Darknet Reference was the most accurate image-classification CNN, classifying images containing hair fescue and sheep sorrel with F1-scores of 0.96 and 0.95, respectively at 1280 × 736. MobileNetV2 achieved comparable results at the lowest resolution, 864 × 480, with F1-scores of 0.95 for both weeds. Training dataset size had minimal effect on accuracy for all CNNs except Darknet Reference. This technology can be used in a smart sprayer to control target specific spray applications, reducing herbicide use. Future work will involve testing the CNNs for use on a smart sprayer and the development of an application to provide growers with field-specific information. Using CNNs to improve agricultural efficiency will create major cost-savings for wild blueberry producers.

Alien plant species on roadsides of the northwestern Patagonian steppe (Argentina).

The introduction of alien species represents one of the greatest threats to biodiversity worldwide. Highway construction increases the dispersal and invasion of exotic plant species. This study examined the assembly process of the plant communities to determine whether the roadsides of the Patagonian steppe represent a reservoir and dispersal source of invasive exotic species. We analyzed the composition of exotic and native species and functional groups present in the established vegetation and seed banks of roadsides and reference areas nearby. The type of dispersal of exotic and native species at the roadsides was also evaluated. Total cover and that of exotic and native species was lower at the roadsides than in the reference areas; however, at the roadsides the cover and seed abundance of exotic species was higher than that of native species. In the roadsides vegetation, native shrubs such as Acaena splendens predominated, along with exotic perennial herbs and grasses which were mainly represented by Rumex acetosella. In the seed bank the predominant species were exotic perennial herbs, also represented by R. acetosella, annual exotic species such as Epilobium brachycarpum and Verbascum thapsus, and annual native species such as Heliotropium paronychioides. No exotic shrubs were found either at the roadsides or in the reference areas. The species at the roadsides did not present a dominant type of dispersal. The abundance of exotic species at the roadsides, both in the aboveground vegetation and the seed bank, may be due to the stressful environment and the characteristics of the species themselves, such as the ability to form seed banks. This work revealed that the roadsides of the Patagonian steppe constitute reservoirs of invasive exotic species, highlighting the importance of identifying them and controlling their spread, with a view to generating ecosystem management programs.

Physicochemical standardisation of the homoeopathic drug Rumex acetosella and its comparison with another homoeopathic drug, Rumex crispus

Background: Rumex acetosella, a relatively new drug in the homoeopathic system, is traditionally used for treating inflammation, diabetes and gastrointestinal problems, especially diarrhoea. Objective: The aim of this work is to report physicochemical standardisation of the homoeopathic drug, Rumex acetosella. Further, we propose our simple and economical method to differentiate it with a closely related species, Rumex crispus. Materials and Methods: The physicochemical study measuring several parameters was done. The pH of the mother tincture (MT) and the water extract was measured and compared. Furthermore, the chemical composition of the Rumex acetosella MT were compared with taxonomically closely related Rumex crispus MT by thin layer chromatography (TLC). Results: The results show a strong relationship between the extracting solvent's polarity and its extracting power. A simple TLC study shows a strong correlation between two drugs of the same genus, Rumex, but they can be differentiated by their unique spots. Conclusion: Our study not only provides the physicochemical standards for the drug Rumex acetosella but also shows that a simple analytical technique, a manual TLC can easily be used to distinguish two taxonomically close homoeopathic drugs.

Weed Survey of Nova Scotia Lowbush Blueberry (Vaccinium Angustifolium Ait.) Fields

ABSTRACT Weed surveys provide the basis for weed management research in lowbush blueberry, but have not been conducted in Nova Scotia since 2001. Documented declines in herbicide efficacy, loss and/or acquisition of herbicide active ingredients, confirmation of herbicide-resistant weed biotypes, and documented vectoring of weed seeds by machinery necessitate a new weed survey. A total of 165 bearing year lowbush blueberry fields were surveyed from 2017 to 2019, within which approximately 211 weed species were identified. Most weed species were herbaceous perennial forbs (89 species) and woody perennials (50 species), followed by annual broadleaf (24 species) and perennial grass weeds (20 species). The remaining flora consisted of a range of ferns, biennials, sedges and rushes, and orchids. The most common weed species were red sorrel (Rumex acetosella L.), poverty oatgrass (Danthonia spicata L. Beauv.), haircap moss (Polytrichum commune Hedw.), hair fescue (Festuca filiformis Pourr.), narrow-leaved goldenrod (Euthamia graminifolia (L) Nutt.), tickle grass (Agrostis hyemalis (Walter) BSP.), woolly panicum (Panicum lanugosum Ell.), cow wheat (Melampyrum lineare Desr.), bunchberry (Cornus canadensis L.), and yellow hawkweed (Hieracium caespitosum Dumort). Increased occurrence of these weed species is likely the result of documented or observed reductions in hexazinone and terbacil efficacy, confirmation of triazine-resistant biotypes, and common occurrence of seeds of these weed species on machinery. Low crop prices have also caused reduced pronamide use, contributing to increased occurrence of hair fescue. Results are guiding future research priorities for weed management in lowbush blueberry.

Analysis of Standard Medical Plants Potential to Reduce Type-2 Diabetes and Obesity

T2DM is a primary cause of illness and death globally, as well as a significant economic burden. T2DM is becoming increasingly common, implying that more effective preventive and treatment techniques are required. An in vitro research of medicinal plants was conducted to investigate their potential anti-diabetic and anti-obesity effects. Assays for ferric reducing antioxidant power (FRAP) and DPPH• scavenging capacity were performed on hot water (WE) and ethanol (EE) extracts of sweet gale (Myrica gale L.), roseroot (Rhodiola rosea L.), sheep sorrel (Rumex acetosa L.), stinging nettles (Utrica dioica L.), and dandelions (Taraxacumofficinale L.). Study of 3T3-L1 preadipocytes also indicated that Myrica gale EE (54.8%) and nettles (62.2%) strongly reduced in vitro adipogenesis (p0.05). There is a possibility that the polyphenols in these medicinal plants might be used to manage type 2 diabetes and obesity.

Antibacterial Effects of Hydroalcoholic and Aqueous Extracts of Two Medicinal Plants in Comparison with Popular Antibiotics: An In Vitro Study

Background: Acinetobacter baumannii is considered a dangerous and drug-resistant hospital-acquired infection. Nowadays, there has been an increasing interest in the use of herbal drugs. Objectives: This in vitro study was conducted to determine the antimicrobial effects of Rumex acetosella L. and Cucurbita maxima L. on Acinetobacter baumannii in comparison with popular antibiotics. Methods: In this experimental study, after extraction, the antibacterial effects of extracts were determined based on MIC and MBC using broth microdilution. The effects of different concentrations of the extracts on A. baumannii growth were also investigated by the disk diffusion method. The results were compared with choice antibiotics. Results: The results of the study indicated that in broth microdilution, the MIC and MBC of the hydroalcoholic extract of C. maxima and the aqueous extract of R. acetosella were equal (64 and 128 µg/mL, respectively). The MIC and MBC of the hydroalcoholic extract of R. acetosella and the aqueous extract of C. maxima were 128 and 256 µg/mL, respectively, which indicated the weaker effects of these extracts. In the disk diffusion method, the greatest mean diameter of inhibition zone was obtained for R. acetosella extracts (24.83 ± 0.29 and 21.83 ± 0.29 mm for hydroalcoholic and aqueous extracts, respectively). Also, the lowest mean diameter was obtained for C. maxima extracts (10.33 ± 0.58 and 8 mm for hydroalcoholic and aqueous extracts, respectively). Conclusions: This study showed the potent antibacterial effects of R. acetosella and C. maxima. They were even more potent than commonly used antibiotics. Therefore, the plants can be used as antimicrobial agents, as well as pharmaceutical supplements and alternative therapies.

Evaluation of currently registered herbicides for fall bearing year red sorrel (Rumex acetosella L.) management in lowbush blueberry (Vaccinium angustifolium Aiton)

Red sorrel is a common creeping herbaceous, perennial weed species in lowbush blueberry fields and reproduces asexually via ramets from creeping roots. Ramets emerge throughout the season but remain vegetative due to a vernalisation requirement for flowering. This weed may therefore be managed with fall herbicide applications, but few currently registered herbicides have been evaluated for fall red sorrel management in lowbush blueberry. The objectives of this research were to (i) determine the effect of various herbicide treatments on red sorrel shoot and root biomass in the greenhouse, (ii) determine the effect of fall bearing year herbicide applications on overwintered red sorrel ramet density in the field, (iii) determine if reduced overwintered ramet density reduces flowering ramet density in the field, and (iv) estimate the potential for red sorrel to recover from fall bearing year herbicide applications. Dicamba, tribenuron-methyl, and glufosinate reduced red sorrel shoot and root biomass in the greenhouse and reduced overwintered ramet density in the field. Clopyralid, sulfentrazone, and flumioxazin reduced shoot and root biomass in the greenhouse but exhibited limited efficacy in the field. Nicosulfuron + rimsulfuron and glyphosate were ineffective in both the greenhouse and field. Dichlobenil and pronamide reduced overwintered ramet density in the field. Reduction of overwintered ramet density did not consistently reduce flowering ramet density. Dichlobenil reduced seedling density at two sites, but no herbicide consistently reduced summer non-bearing year ramet density. Fall herbicide applications alone, therefore, do not appear to maintain red sorrel suppression in lowbush blueberry fields.

How Does the Engineering Species Affect Forest Ecosystems? Changes in Germination and Development Rate of Non-Forest Species Under the Nests of Ardea cinerea L.

Abstract An ecosystem engineer is a species that indirectly changes the availability of resources for other organisms via physical modification of the habitat. A good example of such species is Ardea cinerea L. – a big waterbird that forms colonies up to a few hundreds of nests during the breeding season. The colonies modify the habitat in the close vicinity of the nests mainly through heavy input of organic matter (feces, dropped or regurgitated food leftovers, eggshells, dead birds, etc.), which in turn affects vegetation. In our previous study, we observed that the probability of occurrence of non-forest species under the nests was 29.5 times higher in control plots in two types of forest vegetation (oligotrophic pine forest and riparian mixed forest). Adaptation for long-distance dispersal turned out to be insignificant for the probability of species occurrence, which suggested that the diaspores of those species must have been present in the forest soil before the establishment of the grey heron colony. In the present study, we used the seedling emergence method to compare the structure of the soil seed bank in breeding sites and control plots in two forest ecosystems mentioned above. We also tested whether the increased amount of nitrates in soil had a positive effect on the rate of germination and growth of seedlings. The results have shown that some reservoir of ruderal species was indeed present in the control plots, although their amount was higher under the heronries. We have proved that the number of germinating seeds of ruderal species depends on the concentration of nitrate in the soil of the pine forest. Comparison of the dry weight of 30- and 60-day-old seedlings of Rumex acetosella (pine forest) and Betula pendula (riparian forest) from the control and breeding sites showed an increased size of seedlings coming from the breeding sites of both forest communities.

Inhibitory potential on key enzymes relevant to type II diabetes mellitus and antioxidant properties of the various extracts and phytochemical constituents from Rumex acetosella L.

Type II diabetes mellitus is a common and costly disease worldwide, characterized by hyperglycemia. Alpha (α)-amylase and α-glucosidase are important targets in diabetes therapy. Inhibition of these enzymes may lessen hyperglycemia, preventing diabetic complications. Oxidative stress is another factor involved in the disease's etiology. In the present study, we investigated antidiabetic profiles of the various extracts and phytochemicals of Rumex acetosella. Since the plant has been traditionally used for the antidiabetic purposes. α-amylase and α-glucosidase inhibitory studies in addition to DPPH•, ABTS•+, radical scavenging, and phosphomolybdate antioxidant assays were performed to evaluate the antidiabetic property. Specifically, the ethanol and ethanol-water extracts remarkably inhibited α-glucosidase than that of acarbose, unlike their slight/no inhibition on α-amylase. Convincing α-glucosidase inhibitory and antioxidant potential of alcohol-including extracts verified the ethnobotanical use of R. acetosella as an antidiabetic agent. PRACTICAL APPLICATIONS: The incidence of Type II DM is rising globally. Reducing hyperglycemia holds great importance to prevent devastating outcomes of diabetic complications. Ethnobotanical use of natural sources for medical purposes provides a basis for their potential activity against various diseases. The introduction of herbal agents may lead to the development of new drug candidates with convincing activity. Rumex acetosella L. has been traditionally used for the antidiabetic purposes. The research pointed out various extracts and phytochemical constituents from R. acetosella may act as antihyperglycemic agents. Particularly, alcohol-including extracts of R. acetosella may be considered as promising alternatives in the prevention or treatment of type II DM. The study puts emphasis on the therapeutic value of the plants for antidiabetic medication.

Вплив гербіцидів на забур'яненість культур сосни звичайної (Pinus sylvestris L.) в умовах Київського Полісся

Наведено результати досліджень щодо випробовування гербіцидів під час здійснення хімічних доглядів за лісовими культурами. Для дослідів використано гербіциди Річард, Пікадор, Гліфовіт і Булон у комбінації з прилипачем Олемікс і без нього. На дослідній ділянці трав'яна рослинність була представлена типовими для Київського Полісся видами: куничник наземний (Calamagrostis epigejos (L.) Roth.), злинка канадська (Erigeron canadensis L.), щавель горобиний (Rumex acetosella L.), тонконіг звичайний (Poa trivialis L.), напівчагарник ожина (Eubatus). Найбільш забур'яненими були міжряддя. Тут переважав куничник наземний, а однорічні бур'яни, переважно злинка канадська, траплялися поодиноко. На схилі і дні борозен також переважав куничник та у незначній кількості росли однорічні види. На дні борозен і на їх схилах кількість бур'янів була практично однаковою. Досліди закладено на лісових культурах 2018 року. Культури створено у лісовому фонді ДП "Київська лісова науково-дослідна станція" на суцільному зрубі, по борознах, в умовах свіжого субору. Доповнення культур здійснювали навесні 2019 року. Для обробляння рослин використовували ручні оприскувачі. Під час хімічного догляду за лісовими культурами сосни звичайної (Pinus sylvestris L.) гербіцидна дія препаратів полягала у пригніченні росту небажаної трав'яної рослинності та в частковому її знищенні. Застосування гербіцидних препаратів Річард, Гліфовіт і Булон призвело до знищення від 52 до 68 % багаторічних бур'янів. Найменше багаторічників було знищено гербіцидом Пікадор, тільки 37 %. Причому такий результат було досягнуто як застосуванням препарату Пікадор у комбінації з прилипачем Олемікс, так і без нього. Водночас, Пікадор повністю знищив однорічні бур'яни. Стосовно дії гербіцидів у комбінації з прилипачем встановлено, що його застосування істотно не впливало на ефективність гербіцидів. Усі гербіциди спричинили відпад сосни. Найбільше пошкоджень (21 %) виявлено під час застосування гербіциду Річард. Встановлено, що хімічний догляд негативно вплинув на однорічні рослини сосни звичайної, якими було доповнено лісові культури.

Turning Meadow Weeds Into Valuable Species for the Romanian Ethnomedicine While Complying With the Environmentally Friendly Farming Requirements of the European Union's Common Agricultural Policy.

The cross-compliance mechanism of the European Union (EU)'s common agricultural policy (CAP) makes the approval of the direct payments to the European farmers subject to compliance with the requirement to maintain the land in good agricultural and environmental condition. One of the obligations of the Romanian land owners and farmers is to avoid the installation of unwanted vegetation on their land plots. This vegetation is represented by some species of herbaceous or woody plants, annual or perennial, that spontaneously invade the agricultural lands, diminishing the production capacity of the cultivated plants. Included in this category are 10 meadow weeds, without fodder value or even toxic to animals: Arctium lappa L., Carduus nutans L., Conium maculatum L., Eryngium campestre L., Euphorbia cyparissias L., Pteridium aquilinum (L.) Kuhn, Rumex acetosella L., Veratrum album L., Xanthium spinosum L., and Xanthium strumarium L. Various and multiple uses in traditional medicine of these meadow weed species have been reported for Romania and other nine neighboring East European countries, i.e. Bosnia and Herzegovina, Bulgaria, Czech Republic, Estonia, Kosovo, Russia, Turkey, Serbia, and Ukraine. For A. lappa were recorded the highest number of ethnomedicinal uses, in the largest number of East European countries, including Romania. C. maculatum and V. album are not recommended for human consumption but can be further investigated as potential sources of pharmaceutically active compounds. Once removed by landowners and farmers from their land, the raw plant material of these 10 species become readily and easily available to the Romanian local communities and the industry of herbal food supplements, while the biodiversity of the agro-ecosystems is maintained.

The impact of recent land-use change in the Araucaria araucana forest in northern Patagonia

Land-use change in the form of extensive Pinus plantations is currently altering the natural vegetation cover at the forest–steppe ecotone in northern Patagonia. Providing recommendations for conservation efforts, with respect to this recent and earlier land-use changes, requires a longer time perspective. Using pollen analysis, we investigated to what degree the colonization of the area by Euro-American settlers changed the forest composition and the vegetation cover, and to explore the spread of the European weed Rumex acetosella. This study is based on short sediment cores from six lakes in the Araucaria araucana forest region, across the vegetation gradient from the forest to the steppe. Results document that although Araucaria araucana has been extensively logged elsewhere, near the investigated sites, populations were rather stable and other elements of the vegetation changed little with the initiation of Euro-American settlements. A reduction of Nothofagus dombeyi-type pollen occurred at some sites presumably due to logging Nothofagus dombeyi trees, while toward the steppe, Nothofagus antarctica shrubs may have been removed for pasture. The appearance of Rumex acetosella pollen is consistent with the initiation of land use by Euro-American settlers in all cores, probably indicating the onset of animal farming. The rise of the Rumex acetosella pollen curve during the 1950s marks more recent land-use change. These observations indicate that the spread and local expansion of the weed requires disturbance. Overall, the study shows that the initial colonization of the area by Euro-American settlers had little effect on the natural vegetation structure, while developments since the 1950s are strongly altering the natural vegetation cover.

Interactions between nurse-plants and an exotic invader along a tropical alpine elevation gradient: growth-form matters

Conceptual models of how interactions with native species influence invasions emphasize competition, but recent evidence suggests facilitation can promote invasion in stressful environments. However, how nurse-plants with contrasting growth-forms and distribution interact with invaders remains unexplored, although it could offer insights on nurse/exotic interaction mechanisms. We asked whether shrub and cushion nurses differed in their effects on the exotic Rumex acetosella in sites at four elevations in the high tropical Andes (4100–4400 m), shrubs dominating the lowest sites and cushions the highest sites. During the dry season, we measured soil organic matter (SOM) and water content (SWC) under the shrub Hypericum laricifolium, the cushion Azorella julianii, and adjacent areas outside. We compared Rumex’s performance under each situation, measuring midday leaf temperatures (Tleaf), vapor pressure deficit (VPD), minimum water potentials (Ψmin) and leaf nitrogen (Nleaf) and compared the number, size and proportion of fruiting ramets within sampling rings in each situation. SOM and SWC were higher at all elevations under cushions, then under shrubs and lower outside. Rumex’s density was generally reduced under shrubs but increased on cushions. However, both nurses had positive effects along the gradient on Rumex’s size, reproduction, water balance and Nleaf, shrubs having stronger effects on Tleaf and VPD and cushions on Nleaf. Our results indicate that alternating nurses influenced an invader’s physiological performance to different extents via contrasting effects on shading and soil resources, leading to mixed competitive/facilitative effects of shrubs on the exotic’s demography, while cushions had more consistent facilitative effects across elevations.

Tillage and weed control effect on weeds and wheat productivity

A 3-year study was conducted to assess the impact of tillage and weed control practices on weed flora and wheat productivity. Experiments were conducted during Rabi season of 2012–13 to 2014–15 at GBPUA&T, Pantnagar, with clayloam soil. There were five crop establishment methods, viz. Transplanted rice (conventional tillage) (TPR)- wheat (conventional tillage) (CTW) (TPR-CTW), Transplanted rice (conventional tillage)- wheat (zero tillage)-Sesbania green manuring (S) (TPR-ZTW-S), Direct-seeded rice (conventional tillage)-wheat (conventional tillage)-Sesbania incorporation (S) (DSR-CTW-S), Directseeded rice (zero tillage)-wheat (zero tillage)-Sesbania brown manuring (S) (ZTR-ZTW-S) and Direct-seeded rice (zero tillage) + residue retention-wheat (zero tillage) + residue retention-Sesbania brown manuring (S) (ZTR + R-ZTW+R-ZTS) and three weed control methods [(weedy check, recommended herbicide (Recommended ready-mix herbicide clodinafop 15% + MSM 1% (60 + 4 g/ha) and integrated weed management i.e., clodinafop 15% + MSM 1% 60 + 4 g/ha fb manual weeding at 45 days after seeding (DAS)]. Continuous zero-till cropping system along with residue retention and brown manuring of Sesbania has resulted in the lowest total weed biomass at 60 DAS and greatly reduced the density of Phalaris minor, Medicago denticulata, Polygonum plebeium and Coronopusdidymus. However, density of C. didymus, Rumex acetosella and Vicia sativa was reduced under conventionally tilled wheat. Ready mix application of clodinafop 15% + MSM 1% supplemented with one hand weeding at 45 DAS greatly reduced the density and biomass of weeds. The maximum wheat grain (4.5 t/ha) and straw (6.3 t/ha) yields was achieved under zero-tilled wheat with rice residue retention and Sesbania as brown manure. The integration of clodinafop 15% + MSM 1% with 1 HW at 45 DAS resulted in an increase in grain and straw yields by 45.5% and 30.8%, respectively, over weedy check. It may inferred that in wheat cultivation conventional tillage could be replaced with zero-tillage along with residue retention by growing of Sesbania and the application of 2,4-D at 30 days stage to attain sustainability of ricewheat cropping system.

Highly patterned primary succession after fluvial deposition of mining waste

This study examined early stages (3-5 years) of spontaneous primary vegetation succession on a model locality drastically altered by long term fluvial deposition of copper tailings in Eastern Serbia. In a large-scale survey, 115 samples of herbaceous vegetation (with a total of 75 species) were harvested from standardized 1m x 1m quadrates, and concomitant soil samples collected and their relevant physicochemical properties analysed. Primary succession depended on the establishment of five pioneer species (Rumex acetosella, Agrostis capillaris, Calamagrostis epigeios, Persicaria lapathifolia and Chenopodium botrys). Unconstrained ordination showed very clear vegetation gradients, significantly correlated with the key soil constraints (from Cu excess to low pH and nutrient deficiency), while the distribution of the five edificatory pioneers showed high degree of dependence on the micro-level habitat conditions. This work demonstrates that in such a complex setup with severe abiotic filtering, sufficient sampling effort can reveal strong patterns in a process commonly considered very stochastic.

Invasive and potentially invasive plant species in State Nature Biosphere Reserves of the Altai Republic (Russia)

In the Altaiskiy and Katunskiy State Nature Biosphere Reserves we registered 44 alien plant species, which were considered in Siberia as invasive and potentially invasive. Among them, there were 30 xenophytes and 14 ergasiophytes species. Rumex acetosella L., Impatiens glandulifera Royle, Galinsoga ciliata (Rafin.) Blake, and Strophiostoma sparsiflorum (Mikan ex Pohl) Turcz. are considered invasive in the Altaiskiy Reserve because they actively spread there in natural and seminatural plant communities and habitats. Most of the species had appeared in the territories of the reserves before their establishment as a result of agricultural activity or appeared after their establishment because of activity of the reserves themselves. Despite of a big amount of tourists in the reserves, the invasive and potentially invasive plants are absent on the ecological paths at present.

Measuring competitive impact: Joint‐species modelling of invaded plant communities

AbstractNon‐native species can dominate plant communities by competitively displacing native species, or because environmental change creates conditions favourable to non‐native species but unfavourable to native species. We need to disentangle these mechanisms so that management can target competitively dominant species and reduce their impacts.Joint‐species distribution models (JSDMs) can potentially quantify competitive impacts by simultaneously modelling how species respond to environmental variation and to changes in community composition. We describe a JSDM to model variation in plant cover and show how this can be applied to compositional data to detect dominant competitors that cause other species to decline in abundance.We applied the model to an experiment in an invaded grassy‐woodland community in Australia where we manipulated biomass removal (through slashing and fencing to prevent grazing by kangaroos) along a fertility gradient. Non‐native species dominated plant cover at high fertility sites in the absence of biomass removal. Results from the JSDM identified three of the 72 non‐native plant species (Bromus diandrus,Acetosella vulgarisand especiallyAvena fatua) as having a strong competitive impact on the community, driving changes in composition and reducing the cover of both native and non‐native species, particularly in the absence of grazing. The dominant non‐native grassesBromus diandrusandAvena fatuawere among the tallest species in the community and had the greatest impact on shorter‐statured species, most likely through competition for light under conditions of high fertility and low grazing.Synthesis. We demonstrate a method to measure competitive impact using a joint‐species distribution model, which allowed us to identify the species driving compositional change through competitive displacement, and where on the landscape competitive impacts were greatest. This information is central to managing plant invasions: by targeting dominant non‐native species with large competitive impacts, management can reduce impacts where they are greatest. We provide details of the modelling procedure and reproducible code to encourage further application.

Синантропная флора западных низкогорий Алтая

Синантропная флора западных низкогорий Алтая

Weed control efficacy and tolerance of Canaan fir to preemergence herbicides

AbstractPRE herbicides are the backbone of a successful weed management program in Christmas tree production. In a 2-yr field study, weed control efficacy and tolerance of newly transplanted Canaan fir to different PRE treatments were evaluated. Herbicide treatments consisted of two rates of each of atrazine plus mesotrione plus S-metolachlor at 561 + 150 + 1,504 and 1,122 + 300 + 3,008 g ai ha−1, flumioxazin at 214 and 429 g ai ha−1, hexazinone plus sulfometuron methyl at 289 + 27 and 480 + 46 g ai ha−1, indaziflam at 20 and 41 g ai ha−1, simazine plus oryzalin at 3,366 + 1,683 and 3,366 + 3,366 g ai ha−1, and a nontreated control. Averaged over 2 yr, all PRE treatments controlled giant foxtail, large crabgrass, and redroot pigweed at least 80% throughout the summer. Only the high rates of atrazine plus mesotrione plus S-metolachlor maintained >80% season-long control of yellow foxtail. Horseweed was controlled >85% with flumioxazin at both rates and at high rates of atrazine plus mesotrione plus S-metolachlor, hexazinone plus sulfometuron methyl, and indaziflam. The season-long PRE control of both red sorrel and wild carrot was maintained ≥80% with atrazine plus mesotrione plus S-metolachlor and hexazinone plus sulfometuron methyl regardless of application rate. By 16 wk after treatment, within-row densities of weeds evaluated in this study were reduced >75% in plots treated with atrazine plus mesotrione plus S-metolachlor at both application rates or hexazinone plus sulfometuron methyl at 480 + 46 g ai ha−1. Within-row weed densities in the nontreated control plots were 50, 32, 36, 25, 27, 31, and 19 plants m−2 for large crabgrass, giant foxtail, horseweed, redroot pigweed, red sorrel, wild carrot, and yellow foxtail, respectively. No discernible injury was observed in Canaan fir with any PRE treatment in both study years.

Ethnic and religious affiliations affect traditional wild plant foraging in Central Azerbaijan

Gathering and consuming wild food plants are traditional practices in many areas of the world and their role in fostering food security has been increasingly discussed in recent years. In this field study, we focused on traditional foraging among Azeris, Tats, Russian Molokans, and Udis in Central Azerbaijan. Via 78 semi-structured interviews, with an equal number of individuals from the four ethnic/religious communities, 73 wild food folk taxa were recorded. While Caucasian autochthonous Udis have a restricted use of wild food plants in comparison with the other groups, possibly due to the fact that they live in a plains area that is horticultural-driven and well-connected, the most divergent ethnobotany was exhibited by the Tats (10 folk taxa exclusively used by them) which may be related to both their cultural and geographical isolation and the fact that this community was endogamic until only a few decades ago. Whereas the Azeri plant cultural markers are mainly retained by refugees from Karabakh, Russian Molokans, who represent a distinct, conservative ethno-religious group, seem to have preserved a few ancient Slavic culinary uses of wild plants (Armoracia rusticana Gaertn., B.Mey. and Scherb., Crataegus spp., Rumex acetosella L., and especially Viburnum opulus). Tat cultural markers were represented by barberries (especially in their original lacto-fermented preparation) and Ornithogalum spp., while for Udis Smilax excelsa L. shoots were particularly salient, as were wild Allium, Chaerophyllum, Prangos, Smyrnium, and Tragopogon spp. among the Azeris. Overall, the practice of traditional foraging is alive in the Azeri Caucasus in the most remote mountainous areas and this heritage is the result of a complex co-evolution, in which both human ecological trajectories and cultural attachment to certain plant tastes have possibly shaped specific foraging patterns over centuries.