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The folivorous beetle Cassida rubiginosa was introduced to New Zealand to control the weed, Californian thistle (Cirsium arvense). Although Californian thistle is the primary host, many other thistles are accepted hosts. The objective of this study was to test if the beetle can reduce the fitness of marsh thistle (Cirsium palustre). A potted plant experiment was established with four treatments (0, 50, 100, and 200 larvae/plant). Plant growth (width, height, and number of branches) and reproductive performance (number of flowers, seeds, seed weight and percent germination) parameters were measured. No significant differences were found for any of the measured parameters, except percent germination. Higher larval densities (100 and 200) resulted in approximately 10% less germination compared with lower densities (0 and 50). Under these experimental conditions, C. rubiginosa had minimal impact on the performance of marsh thistle. For the beetle to have an impact, it would likely need to attack smaller, non-bolting rosettes, or be combined with additional stressors that might be encountered in a natural field population.

1. Within the host range of herbivorous insects, performance hierarchies are often correlated with relatedness to a primary host plant, as plant traits are phylogenetically conserved. Therefore, it was hypothesised that differences in herbivore performance on closely related plant species are due to resistance traits that vary in magnitude, rather than in the nature of the traits. 2. This hypothesis was tested by manipulating putative resistance traits of three congeneric thistle species (Cirsium arvense, Cirsium palustre, and Cirsium vulgare) and assessing the performance of the oligophagous, leaf-feeding beetle, Cassida rubiginosa. Measurements were done of survival, weight gain, and development time of the beetle on its primary host, C. arvense, and two alternative hosts under low and high nutrient availability, and on shaved and unshaved leaves. 3. Survival of C. rubiginosa was strongly dependent on plant species with final mean survival rates of 47%, 16%, and 8% on C. arvense, C. palustre, and C. vulgare, respectively. Survival was primarily explained by leaf trichome densities, and to a lesser extent by specific leaf area. Leaf flavonoid concentrations did not explain differences in beetle survival, and there were no differences in beetle weight gain or development time of individuals that survived to adulthood. 4. No beetles survived on unshaved (hairy) C. vulgare plants, but manipulating leaf trichome densities of the thistle species by shaving the leaves moderated the plant-specific resistance, and equalised the survival rates. Survival of C. rubiginosa on alternative congeneric hosts was explained by a common physical resistance trait that varied in magnitude.

Antimicrobial properties of ethanol and water extracts from eight Asteraceae species were investigated against three Gram positive (Staphylococcus aureus, MRSA and Bacillus cereus) and two Gram negative (Escherichia coli and Salmonella typhimurium) bacterial strains. Ethanol extracts from Centaurea scabiosa, Arctium minus, Taraxacum officinale, Centaurea nigra and Cirsium palustre demonstrated antimicrobial activity against strains of S. aureus, MRSA and B. cereus (MIC=187.5-365μg/ml). Ethanol extracts also had higher antioxidant activities and phenolic content demonstrating a link between these compounds and the bioactivity of these extracts. Further investigation into the phenolic content of ethanol extracts using UPLC-MS/MS lead to the identification and quantification of numerous phenolic compounds in all species including; 18 from Cirsium arvense, 16 from Cirsium vulgare, 19 from C. palustre, 15 from C. nigra, 17 from C. scabiosa, 14 from Sonchus asper, 17 from A. minus and 11 from T. officinale.

This study examined a non-soil seed bank deposited inside the tussock cores of Carex cespitosa, a perennial plant with a tussock growth form. Based on the vertical structure of the seed bank in 20 tussock cores, the history of changes in plant species composition during succession in an unmowed grassland in the Bialowieza National Park was reconstructed. Three horizontal layers were distinguished in each tussock core: upper (corresponding to the initial forest stage), middle (transitory stage—forb and swamp communities) and bottom (early successional stage—grassland). The results showed that seeds of both the parental species and other species were stored inside the C. cespitosa tussock cores. More than 50,000 seedlings were found, representing 42 vascular plant species. The highest number of seedlings was recorded in the middle layer. Seedlings of swamp species were dominant in the upper layer, whereas seedlings of grassland species were dominant in the other layers. The highest number of C. cespitosa seedlings was observed in the upper layer. The most common seedlings in the middle layer belonged to the species Epilobium palustre, Lythrum salicaria and Cirsium palustre. In the bottom layer, the most common species of seedlings were grassland species, e.g. Lychnis flos-cuculi and Ranunculus repens. The protected seed bank inside this tussock species reflected recorded changes in species composition of these grasslands through time. Seed banks in this and other tussock-forming species represent a potentially useful tool for reconstructing recent developmental history of plant communities.

To investigate whether floral resource quality impacts on bumble bee floral choices, we determined the pollen foraging constancy and floral choices of four bumble bee species commonly occurring in peaty, wet meadows in South Belgium. We subsequently analyzed the chemical contents of pollen and nectar, as well as the nectar production of the major host plant species. Individuals of B. lapidarius and B. pascuorum collected high-quality pollen (i.e. having high essential amino acid and phytosterol content) on Comarum palustre and Trifolium pratense, whereas individuals of B. terrestris s.l. and B. hypnorum enlarged their diet breadth to less valuable pollen resources (Cirsium palustre and Valeriana repens). Since Persicaria bistorta and Comarum palustre offer abundant and concentrated nectar, these plant species might represent major nectar sources for bumble bee species in peaty, wet meadows. The present study demonstrated the role of pollen composition on differences in foraging strategies among bumble bee species., SCOPUS: ar.j, info:eu-repo/semantics/published

It was found that weak chemiluminescence of manganese(IV)-hexametaphosphate-formaldehyde system was greatly enhanced by plant polyphenolic compounds. Based on this finding, a new flow injection chemiluminescence method (FI-CL) was developed for the determination of the total content of polyphenols in plant extracts. The calibration graph obtained for standard solutions of 6-hydroxyluteolin 7-O-glucoside (6OHLG) was linear in the range 0.001-0.8 μg mL(-1). The method was simple, rapid (203 samples h(-1)) and sensitive with a detection limit of 0.25 ng mL(-1). The FI-CL method was successfully applied to the determination of the total polyphenols content (as 6OHLG equivalents) in methanolic, ethyl acetate and aqueous extracts from leaves of Cirsium palustre (L.). Two types of solvent extraction methods (reflux and ultrasound assisted extraction) were used and compared in terms of extraction efficiency. A positive, significant linear correlation between the results obtained by FI-CL method and spectrophotometric methods was observed.

Ten flavonoids belonging to the subclasses of flavones, flavanones and aurones were isolated from methanolic extract of Cirsium palustre leaves after multistep chromatographic separation. Their structures were elucidated with spectroscopic methods. All compounds, except for luteolin 7-O-glucoside, were isolated for the first time. Four compounds—eriodictyol 7-O-glucoside (6), 6-hydroxyluteolin 7-O-glucoside (11), scutellarein 7-O-glucoside (12) and pedalitin (14)—were tested for their effect on collagen expression in normal human dermal fibroblasts. Among them, compound 11 at 40 μM and compound 14, at all concentrations used (1, 20, 40 μM), significantly enhanced the level of total collagen secreted into the medium. Furthermore, compound 11 significantly stimulated type I collagen expression, whereas compound 14 activated type I and III collagen expression at the mRNA level, depending on concentration. MMP-2 activity was inhibited by all study compounds, with the greatest effect recorded with compound 14 at 20 μM. The lack of effect on collagen content in the medium of compound 6- and compound 12-treated cells, besides an increase in COL1A1 and COL1A2 expression, might be caused by diminished expression of HSP47 gene, resulting in decreased procollagen secretion. Future study of compounds 11 and 14 for their potential therapeutic use in conditions connected with collagen biosynthesis deficiency is required. Copyright © 2014 John Wiley & Sons, Ltd.

The addition of a novel host plant to a phytophagous insect's diet may result in subsequent host-plant specialisation, and is believed to be a key cause for speciation in this trophic group. In northern Britain, the tephritid fly Tephritis conura has experienced a unique host-plant expansion, from the melancholy thistle Cirsium heterophyllum to the marsh thistle C. palustre. Here, we examine whether the incorporation of C. palustre in the repertoire of British T. conura flies has caused genetic divergence between populations infesting the old host and the novel host, and how British populations differ from populations infesting C. heterophyllum in continental Europe where C. palustre is not infested. No evidence for restricted gene flow among British C. palustre and C. heterophyllum flies was found. Significant differentiation between British and continental T. conura was found at only one allozyme locus, hexokinase, and caused by a new allele, Hex_95. Hexokinase is related to host-race formation in continental European flies infesting C. heterophyllum and C. oleraceum, and might be linked to loci determining host choice. Based on morphological and phenological data from previous studies, we suggest that T. conura in Britain has adapted to the novel host but that host-race formation is impeded by similar plant phenologies.

Whether or not a host plant is incorporated into a phytophagous insect's diet depends on both the insect's ability to colonize the novel host and the host plant's susceptibility to the insect. The latter, again, will be influenced by the genetic structure of the host plant. Cirsium palustre (marsh thistle) is heavily infested by the tephritid fly Tephritis conura in northern Britain, whereas infestation is not only absent in southern England, but also absent on the European continent where T. conura is common on other Cirsium. To understand why regional infestation patterns evolve, we studied how genetic structure and phylogeographic ancestry of C. palustre are related to the probability of infestation in Britain. The probability of infestation in Britain was related neither to phylogeographic lineage (two lineages were observed in Europe), nor to introgressive hybridization with the original host of T. conura, C. heterophyllum. However, infested British C. palustre were strongly genetically deprived. British C. palustre showed continuous loss of genetic variability towards the northern range edge. The loss was explained best by genetic drift during geographic range expansion, rather than by genetic drift in isolated patches or mating system change from predominately outcrossing to selfing. The phylogeographic pattern of C. palustre strongly suggests Scotland as the geographic origin of a recent host-plant expansion of T. conura. © 2008 The Linnean Society of London, Biological Journal of the Linnean Society, 2008, 95, 221–232.

In the hexane extract of C. palustre and C. rivulare fruits, fatty acids, sterols, triterpenes, and volatile compounds were analyzed by the GC-MS-FID method. In the methanolic extracts, total phenol content was estimated. The antioxidant activity of both extracts was measured with DPPH assay and expressed in % scavenged DPPH.

Summary 1. Many flowering plant species have a facultative or obligate dependence on insect pollination for reproductive success. Anthropogenic disturbance may alter these species interactions, but the extent to which structural changes to plant-pollinator networks affect plant species mating systems is not well understood. 2. We used long-term livestock grazing of a birch wood ecosystem to test whether disturbance of this semi-natural habitat altered floral resources, the structure of plant–insect visitation networks and the mating system of a focal plant species, Cirsium palustre. 3. Grazed habitat had a higher species richness of floral resources for pollinators. Visitation networks in grazed habitats were larger, more diverse, with an increase in the number of pollinators per plant species. Controlling for sampling effects, however, showed networks in grazed habitats were less nested and revealed a positive correlation between network connectance and floral species richness. 4. Network connectance was negatively related to C. palustre outcrossing rate within grazed and ungrazed sites. However, on average, the effects of grazing, including greater mean connectance, produced higher overall outcrossing rates and more pollen donors compared with ungrazed habitat. The number of different pollen donors, spatial genetic structure and mating among close relatives were all correlated with greater extent of suitable C. palustre habitat in the landscape, consistent with the effects of increasing plant population size but limited seed dispersal. 5. Pre-adaptation of C. palustre to disturbance coupled with a preponderance of highly dispersive flies attracted to the greater food resources in grazed habitat is a likely mechanism underpinning this increased pollen transport. 6. Habitat modification by long-term mammalian grazing fundamentally shifted visitation network structure and the state of a plant mating system, indicating how ecosystem disturbance can cascade across levels of biological organization through altered interspecific interactions. Cirsium palustre retains flexibility to bias reproduction towards selfing where pollen donor diversity is limited; such reproductive flexibility may be an important mechanism structuring plant populations in human-modified landscapes.

Summary 1. Both resources and natural enemies can influence the distribution of a herbivore. The ideal free distribution predicts that herbivores distribute themselves to optimise utilisation of resources. There is also evidence of herbivores seeking out refuges that reduce natural enemy attack (enemy-free space). Which of these theories predominates in a thistle–tephritid Terellia ruficauda (Diptera: Tephritidae)–parasitoid interaction is examined. 2. The plant, Cirsium palustre, had a contagious distribution approximated by the negative binomial distribution. Terellia ruficauda foraged preferentially and oviposited on isolated plants although its larvae gained neither nutritional benefit nor reduced natural enemy pressure from such behaviour. 3. Parasitoids of T. ruficauda foraged and oviposited more frequently on isolated than on crowded T. ruficauda, resulting in inverse density-dependent parasitoid attack at all spatial scales examined. Neither the herbivore nor natural enemies distributed themselves according to the predictions of the ideal free distribution and the herbivore did not oviposit to reduce natural enemy attack. 4. Extrapolating from the theoretical predictions of the ideal free distribution and enemy-free space to the field requires considerable caution. Terellia ruficauda and its parasitoids appear to select their oviposition sites to spread the risk of losses through factors (e.g. mammal herbivory) that may damage dense clusters of C. palustre.

The first method for the simultaneous determination of polyphenolic antioxidants in extracts from leaves of Cirsium palustre based on high performance liquid chromatography combined with flow injection chemiluminescence detection (HPLC-FI-CL) has been developed. The extracts were prepared by using methanol as extraction medium and two types of extraction methods (reflux and ultrasound assisted extraction). The post-column CL determination of polyphenols was based on their enhancing effect on the chemiluminescence intensity generated in manganese(IV)–hexametaphosphate–formaldehyde system in a phosphoric acid medium. Main antioxidants determined in C. palustre leaves were eriodictyol-7- O -glucoside, luteolin-7- O -glucoside and 6-hydroxyluteolin-7- O -glucoside belonging to flavonoids, and chlorogenic acid belonging to phenolic acids. Chromatographic separation was carried out on a C18 column with gradient elution by using a mobile phase containing 0.25% (v/v) phosphoric acid in water (solvent A) and 100% methanol (solvent B). Under the optimized conditions of chromatographic separation and CL detection the validation of the method was performed. The calibration curves showed good linearity in the concentration range from 0.5 to 40 µg mL −1 . The HPLC-FI-CL method was successfully applied to the determination of four polyphenolic compounds in methanolic extracts from leaves of C. palustre . The accuracy of the developed method was confirmed by the comparison of the results with those obtained by an HPLC-PDA method. The relative error of determination does not exceed 6.1%. However, the HPLC-FI-CL method is characterized by 40–65 times higher sensitivity compared to the HPLC-PDA method.

A study was undertaken to compare the diet composition of guanacos (Lama guanicoe) and sheep (Ovis aries) when pastured on improved and unimproved Agrostis spp./Festuca spp. dominated grassland typical of the UK uplands. Samples were collected from oesophageal fistulated guanacos and sheep grazing experimental plots that had been grazed previously by either sheep or guanacos. Sward composition and herbage biomass were determined for each plot using quadrat cuts. The sward composition and diet composition results obtained were used to calculate selectivity indices for individual dietary components. Green leaf of broad-leaved grasses was the main dietary component for both animal species on both the improved and unimproved grasslands. In general, the guanacos consumed less green grass leaf and more dead grass leaf than the sheep. Their diets also contained significantly more Nardus stricta than sheep diets. The sheep diets contained significantly more Trifolium repens, which was consistently avoided by the guanacos. Only one dicotyledonous species (Cirsium palustre) was consistently selected by the guanacos. There were fewer between-species differences in diet composition on the previously sheep-grazed plots than on the previously guanaco-grazed plots.

Case studies implementing early detection and rapid response (EDRR) protocols are crucial to our understanding of how to evaluate the threat of a new invasive organism. Most EDRR schematics depict a linear approach to EDRR beginning with detection, then assessment, and concluding with the rapid response. Our case study exemplified the need to adjust this protocol by interlacing all three phases. Our target species is a recent invader to central New York: Cirsium palustre (marsh thistle). We observed 192 populations and reported them on iMapInvasives.org. These locations were used to generate risk maps of neighboring counties. Six test plots evaluated the plant's bienniality and monocarpism. A life-stage analysis allowed us to delineate the invasion front to target control and management solutions where they are most effective for marsh thistle. An adaptive approach to EDRR can expedite response strategies, develop risk maps, and train partners for better control.

The complexes of phytophagous insects associated with the stems of Cirsium arvense (L.) Scop. 1772, Cirsium vulgare (Savi) Ten. 1835-1838, Cirsium palustre (L.) Scop. 1772, Cirsium oleraceum (L.) Scop. 1769, Cirsium eriophorum (L.) SCOP.. 1772, Carduus acanthoides L. 1753 and Carduus mutans L. 1753 (Asteraceae) and their parasitoids were studied in northern Bavaria (FRG), lower Austria and the Alsace (France). The structure of the food-webs is discussed for all host species. A total of 25 phytophagous and 44 parasitoid species was found. 12 herbivorous species were associated with C. arvense, 15 with C. vulgare, 11 with C. eriophorum, 10 species each with C. nutans, C. acanthoides and C. palustre and 4 species with C. oleraceum. None of these species occurred on all plants investigated. Ceutorhynchus litura (Fabricius 1775), C. cf trimaculatus (Fabricius 1775) (Coleoptera: Curculionidae) and Urophora cardui (Linnaeus) 1758 (Diptera: Tephritidae) were monophagous. Out of the other species, the oligophagous Melanagromyza aeneoventris (Fallen) Hendel 1920 (Diptera: Agromyzidae) and Mordellistena cf parvuloides Ermisch 1956 (Coleoptera: Mordellidae) were dominant. Agapanthia villosoviridescens DeGeer 1775 (Coleoptera: Cerambycidae), Myelois cribrumella (Hubner 1796) (Lepidoptera: pyralidae), Cheilosia albipila (Meigen 1838), C. fraterna (Meigen 1830) (Diptera: Syrphidae), Apion onopordi Kirby 1808, A. gibbirostre Gyllenhal 1813 and Lixus elongatus Goeze 1777 (Coleoptera: Curculionidae) were each abundant herbivores on some of the host plants. Average infestation (% stems attacked) by all phytophaga was high, reaching 68% in C. arvense and 90 to 100% in the other thistles. The size of the host plant species influenced the average number of individuals per plant. The phytophagous insects used four different parts of the resource: (1) the pith, with some species depending on a pith channel, (2) self induced gall-tissue, (3) meristematic tissue, (4) roots or root collars. Resource utilization of the main phytophages showed some overlap in time for C. vulgare and C. palustre, but little for C. arvense. A comparison with the Cardueae flowerhead system showed similar patterns in guild tructure in spite of a distinct taxonomic composition

Many plant populations have persistent seed banks, which consist of viable seeds that remain dormant in the soil for many years. Seed banks are important for plant population dynamics because they buffer against environmental perturbations and reduce the probability of extinction. Viability of the seeds in the seed bank can depend on the seed’s age, hence it is important to keep track of the age distribution of seeds in the seed bank. In this paper we construct a general density-dependent plant-seed bank model where the seed bank is age-structured. We consider density dependence in both seedling establishment and seed production, since previous work has highlighted that overcrowding can suppress both of these processes. Under certain assumptions on the density dependence, we prove that there is a globally stable equilibrium population vector which is independent of the initial state. We derive an analytical formula for the equilibrium population using methods from feedback control theory. We apply these results to a model for the plant species Cirsium palustre and its seed bank.

Crude aqueous extracts from leaves of Cirsium arvense, C. oleraceum, C. palustre, C. rivulare and C. vulgare were investigated. The content of tannins in mentioned sources, determined by the weight method with hide powder, varied between 1 and 7.63%. Total phenolic content, analysed by using Folin-Ciocalteau's method, ranged between 54 and 96 mg g(-1), was expressed as milligrams of gallic acid per gram of dry extract. Phenolic acids were identified by HPLC method. Antimicrobial activity of those extracts was examined. Cirsium palustre extract was the most active against investigated microorganisms. It was observed that the content of small-molecular phenolic compounds had greater influence on the activity of extracts than tannins. The total antioxidant activity indicated by radical cation 2,2'-azini-di-(3-ethylbenzthiazoline sulphonate) ABTS(*+), expressed as total antioxidant status (TAS) ranged from 2.31 to 2.78 mM L(-1).

Carduus palustris Linnaeus, Species Plantarum 2: 822. 1753. "Habitat in Europae pratis subpaludosis." RCN: 5950. Lectotype (Talavera & Valdés in Lagascalia 5: 188. 1976): Gmelin s.n., Herb. Linn. No. 966.5 (LINN). Current name: Cirsium palustre (L.) Scop. (Asteraceae)., Published as part of Jarvis, Charlie, 2007, Chapter 7: Linnaean Plant Names and their Types (part C), pp. 370-473 in Order out of Chaos. Linnaean Plant Types and their Types, London :Linnaean Society of London in association with the Natural History Museum on page 385, DOI: 10.5281/zenodo.291971

The extent of within-patch dispersal by a tephritid fly and its four major parasitoids was examined over three field seasons. Hosts and parasitoids were marked using acrylic paint and observed as they oviposited into the flowerheads of marsh thistle, Cirsium palustre. The average recapture rate pooled across all species was 22%. The four parasitoids showed consistently greater rates of movement than the host in all three years. In nearly all comparisons, male dispersal was less than female dispersal. There was no evidence that parasitoids moved longer distances after visiting low quality rather than high quality patches. In the one season it was studied, no correlations between movement and insect size were observed. The relevance of these observations to host-parasitoid population dynamics is discussed.

The composition of the essential oils of Cirsium palustre and C. rivulare and their antiproliferative activity against breast adenocarcinoma cells (MCF-7 and MDA-MBA-231) were investigated. The essential oils obtained by hydro-distillation from the roots (yield 0.2 and 0.1% v/w, respectively), leaves and inflorescences (yield below 0.01%), were analyzed by gas chromatography coupled with mass spectrometry (GC-MS). The composition of the essential oils in the respective organs of each plant differed considerably. On the other hand, similarities were observed in the composition of root and leaf oils. In C. palustre and C. rivulare root oil, 50 and 39 constituents were identified, accounting for 95.3% and 92.4% of the total content. The main components were aplotaxene and its derivatives, representing 78.6% and 46.6% of the total content. In leaf oils of both species, 59 and 49 compounds, respectively, were identified, representing 67.4% and 78.3% of the total content. The major constituents were β-damascenone (4.1% and 13.4%, respectively) and β-ionone (6.7% and 5.3%, respectively). Short-chain saturated and unsaturated aliphatic alcohols and aldehydes constituted another important group of compounds (17.7% and 9.0%, respectively). The essential oils of the roots have moderate anti-proliferative activity, with IC50 values ranging from 110 to 140 μg/mL. These concentrations were below the level able to inhibit the proliferation of healthy cells.

SUMMARY Growth and CO2-exchange were measured on two species in the field layer of ash coppice. Two independent methods for the measurements of photosynthesis were used: the 14CO2-method and the URAS-method. Before coppicing the woodland plant Geum urbanum showed its adaptation to the deciduous woodland environment: a high rate of growth and photosynthesis in the spring light phase, and an adaptation to the shade conditions in summer. The first year after coppicing, Geum showed stunted growth and partly disappeared. Cirsium palustre, on the other hand, germinated after coppicing and demonstrated a high assimilation rate and rapid vegetative growth, which led to abundant blooming in the second year of the coppice cycle.

It is demonstrated that after the feelling of ash coppice Cirsium palustre becomes established from seed that was produced during the previous coppice cycle and has lain underground for several years. These seeds are light-requiring and it is probable that their germination is triggered by exposure to light during coppicing in winter. It is assumed that the seeds become light-requiring because phytochrome in the far-red absorbing form high. This facilitates their incorporation in the seed bank in summer. However, the disappearance of Pfr is inhibited at low temperatures; this means that the seeds can store the light stimulus in winter and will not germinate until they experience higher temperatures in spring. The significance of the inhibition of seed germination under a leaf canopy is that it enhances the seeds chance of being incorporated in the soil seed bank.

Predation by rabbits, Cheilosia grossa and especially Epiblema scutulana considerably reduces achene production in Cirsium palustre and Cirsium vulgare. In both species larger plants in a population are more frequently attacked, however the effect of predation is greater in medium sized plants. As a result the contribution of larger plants to the total achene production of the population is increased.In Cirsium vulgare larger populations are more susceptible to attack. The pattern and consequences of predation are discussed in relation to the occurrence in temporary habitats and to selectional processes. Predation intensifies existing developments in the population biology of these species. To compare the effect of predation for both species, detailed information of their population biology is necessary. At the moment the outcome of the comparison can only be indicated.

In the first years after coppicing, Cirsium palustre is abundant in Dutch ash coppice woodlands and in the second year, it flowers abundantly. In later years the species is nearly absent. In contrast to its behaviour in meadow and spring communities, the species typically behaves as a true biennial in this system. Despite fairly high mortality, the plants flowering in their second year produce enough seeds to replenish the seed bank. It is suggested that the persistence of the species in this system depends on Its ability to form a longlived seed bank and on a nutrient availability high enough to enable some rosettes to exploit the high photosynthetic photon flux density (PPFD) in the first year after coppicing and thus to reach the critical size needed for flowering in the second year. Rosettes persisting to the third year generally do not flower and ultimately die because shading by the tree canopy has become too severe.

SUMMARY The adaptability of Cirsium palustre, a shade avoiding species, and Geum urbanum, a species avoiding exposed conditions in the ash coppice cycle, to a change from a high to a low light intensity was studied, in order to simulate the changes taking place in the light climate in a deciduous woodland in spring. Both the vegetative rosette phase and the generative phase were considered. In the rosette phase a rapid adaptation to the low light intensity took place in both species in a similar way. In the generative phase Geum adapted much better after the plants had been transferred from a high to a low light intensity. The dry weight increase of Cirsium ceased after the transfer, whereas Geum continued to grow. The leaf area ratio was much higher after the transfer, giving better assimilation in limiting light conditions. Cirsium when continuously grown in a low light intensity also had a high leaf area ratio, but the stems were too weak to support themselves, in contrast with Geum. So in the vegetative phase both species can be considered shade tolerant, but Cirsium palustre is not shade tolerant in the generative phase.

SUMMARY The influence of different light intensities on the vegetative growth and CO2-exchange characteristics of Cirsium palustre and Geum urbanum were studied in order to give a possible explanation for the different behaviour of the two species in the ash coppice cycle. The shade avoiding species C. palustre showed shade tolerant characteristics, whereas the species which avoids exposed conditions, G. urbanum, grew well in full daylight. Although there were some minor differences between the two species, the influence of light intensity on vegetative growth gives no sufficient explanation for the observed phenomena in the coppice cycle.

Four species of Cheilosia (Diptera: Syrphidae) were reared from Cirsium palustre in Scotland. The third-stage larva is similar in all four species but each can be recognized by the form of the posterior respiratory process. A modified prothorax and thickened bands of spicules on some of the segments may characterize the plant-boring type of Cheilosia larva. The univoltine Cheilosia grossa oviposits in batches on young stems. With three or more larvae per plant the tip of the stem is killed. The plant responds by producing a mass of basal stems in which larvae subsequently feed. Cheilosia fraterna and Cheilosia proxima do not oviposit in batches and are bivoltine. Cheilosia fraterna attacks mature stems and rosettes. Cheilosia proxima attacks only rosettes. Cheilosia albipila was reared only six times, from stems collected in July. Rates of parasitism were low and only two parasitoid species were recorded.

In European floras Cirsium palustre (L.) Scop. usually is classified as a biennial and monocarpic species. The value of this classification was examined in a population growing in a spring area in Jutland, Denmark. It was possible to describe five ontogenetic states, i.e. life-states, in the population, the seed state excluded. Each Kate normally lasted for one growing season. Therefore the flowering state was generally not reached until in the fifth growing season. Observation on mortality revealed that seedlings were exposed to an extremely high death risk. However, in the other vegetative life states the death risk was rather low and constant.

Ethanol extracts from fresh leaves of Cirsium palustre (L.) Scop. were tested for inhibitory effects on the germination of own seeds, and dried leaves were ground and incorporated in soil to determine if growth of own seedlings was affected. Leaf extracts strongly inhibited seed germination, and leaf residues seedling growth. Inhibition was apparently not mediated by effects on pH or by nutrient deficiency.

The absence of cross-pollination in Cirsium palustre and Cirsium vulgare resulted in reduced achene production while the achenes produced were heavier than those produced after cross-pollimation. Establishment of plants from non-cross-pollinated achenes is comparatively higher, facilitating the founding of a population from isolated individuals in these wind-dispersed species.If achene weight is the result of a balance between cross-pollination and self-pollination (and/or apomixis), the first causing more and thereby lighter achenes to develop, increasing density of flowering individuals in a population may lower achene weight and consequently seedling survival. This may account for the frequently observed decline of populations of fugitive monocarpic perennials.

Extensively managed and flower-rich mountain hay meadows, hotspots of Europe's biodiversity, are subject to environmental and climatic gradients linked to altitude. While the shift of pollinators from bee- to fly-dominated communities with increasing elevation across vegetation zones is well established, the effect of highland altitudinal gradients on the community structure of pollinators within a specific habitat is poorly understood. We assessed wild bee and hoverfly communities, and their pollination service to three plant species common in mountain hay meadows, in eighteen extensively managed yellow oat grasslands (Trisetum flavescens) with an altitudinal gradient spanning approx. 300 m. Species richness and abundance of pollinators increased with elevation, but no shift between hoverflies and wild bees (mainly bumblebees) occurred. Seedset of the woodland cranesbill (Geranium sylvaticum) increased with hoverfly abundance, and seedset of the marsh thistle (Cirsium palustre) increased with wild bee abundance. Black rampion (Phyteuma nigrum) showed no significant response. The assignment of specific pollinator communities, and their response to altitude in highlands, to different plant species underlines the importance of wild bees and hoverflies as pollinators in extensive grassland systems.

(1) Cirsium palustre, Galeobdolon luteum and Sanicula europaea were used in factorial experiments to investigate the effects of two features of vegetational shade: shade density, measured as the percentage transmission of photosynthetically active radiation (PAR), and shade type, measured as the ratio of red to far-red radiation (R/FR ratio). Neutral shade has an unaltered R/FR ratio, filtered shade a low R/FR ratio as under a deciduous tree canopy in summer. (2) The growth of all species was reduced in shade but not proportionately to shade density, partly because of compensatory increases in specific leaf area. Shade type had little or no effect. Plants died under 1 % PAR: Cirsium quickly, Galeobdolon more slowly and Sanicula most slowly of all, but in all cases more rapidly in filtered than in neutral shade. All grew well at 20% PAR and above. (3) Cirsium leaves and Sanicula petioles were longer the less dense the shade and tended to be longer in filtered shade. The lengths of Galeobdolon internodes and petioles were greater in denser shade and in filtered shade. (4) The flowering of Galeobdolon was reduced in filtered shade as well as in dense shade and independently of plant size. The flowering of Sanicula was not affected by shade type but was related to shade density and plant size. (5) Herbaceous woodland plants respond to filtered shade although increased height growth to overtop the shading plants would not be appropriate. Leaf display responses and increases in leaf and petiole lengths help to optimize PAR interception among the ground vegetation.