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We present a genome assembly from an individual Ilex aquifolium (the English holly; Eudicot; Magnoliopsida; Aquifoliales; Aquifoliaceae). The genome sequence is 800.0 megabases in span. Most of the assembly is scaffolded into 20 chromosomal pseudomolecules. The assembled mitochondrial and plastid genomes have lengths of 538.43 kilobases and 157.52 kilobases in length, respectively.

Paratylenchus ilicis n. sp. was found associated with holly in the Netherlands and was described based on morphology, morphometrics, rRNA and mitochondrial cox1 genes, phylogenetic relationships with other Paratylenchus species, host information and geographical distribution. This species can be morphologically diagnosed based on its light brown, slightly obese to obese females with tubercles on cuticle, lateral bands widening into an ovoid field around vulva level, stylet length of 70 μm to 100 μm, outstretched to reflexed ovary, rounded sperm-filled spermatheca, vagina opening into a thick-walled rounded space, absence of vulval flaps and vulva at 89% to 95% of body length, very short tail in all life stages, and a characteristic finger-like tail tip in juveniles (J2). The new species is morphologically closest to Cacopaurus pestis but differs based on the absence of a scutellum-like differentiation in the lateral field, the ovaries that can be outstretched or reflexed, and the finger-like tail tip in J2. Furthermore, both species were found to be molecularly distant from one another, found in different habitats, and are associated with different hosts. The high morphological similarity between Cacopaurus and Paratylenchus and our phylogenetic analyses, revealing that the former is embedded within different Paratylenchus clades and thus polyphyletic, provide new evidences for the synonymization of Cacopaurus with Paratylenchus.

Resprouting species, such as English holly (Ilex aquifolium L.), can be severely affected by long-lasting forest management. In the present study, the clonal and fine-scale spatial genetic structure (FSGS) of English holly are evaluated in a sub-Mediterranean mixed forest of Central Spain, where this species was subjected to different and intense human interventions for centuries, including coppicing in dense structures and in open woody pastures. Using seven microsatellite loci, we assessed the contribution of clonal and sexual reproduction to the diversity of holly in both areas and the fine-scale genetic structure was evaluated. For the dense coppiced area, the results showed high clonal diversity derived mainly from stem resprouting. Stems were separated an average of 3 m and up to 10 m, and dense aggregations of stems sometimes included various genotypes. The results also showed recent seed recruitment leading to small unique and isolated genotypes. Furthermore, FSGS was detected at close distances as being stronger in the coppiced area than in the open woody pasture area, especially for individuals of greater diameter at breast height. The results obtained suggest that current management strategies are not negatively affecting the genetic diversity of this species. [ABSTRACT FROM AUTHOR]

Plants of the genus Ilex are widespread throughout the world, with its best-known representative being Ilex paraguraiensis from South America. The European species Ilex aquifolium shows similarities in its terpenoid, sugar and phenolic acid profiles. Using aqueous extracts of Ilex aquifolium as a supplement in Wistar rats showed that, despite the lack of caffeine, it had strong hypocholesterolemic effects. In addition, a reduction in oxidative lipid degradation and a decrease in hepatic steatosis in histopathological studies were observed. The results of this study suggest that extracts from the European species Ilex aquifolium may have potential as an alternative treatment for hyperlipidemia.

The morphological properties of Trochila ilicina (Helotiales, Ascomycota), a fungus previously not recorded in Poland, were described and illustrated. Trochila ilicina was associated with living, decaying and fallen leaves of Ilex aquifolium. However, this fungus formed apothecia only on leaves isolated from their plant host. Hence, T. ilicina was considered both a weak parasite and a saprotroph preferring decaying and necrotic leaves, and not only a saprotroph as all earlier published data suggested. This fungus has been found in different places of Szczecin, as well as in the Arboretum Glinna and the Arboretum Przelewice, north-western Poland. Additionally, the known distribution of T. ilicina in the world is presented.

Species of Calonectria are common saprobes and plant pathogens on a wide range of hosts occurring in subtropical to tropical regions of the world. The aim of the present study was to resolve the status of new Calonectria collections obtained on Ilex leaves from France. Based on DNA sequence data of their β-tubulin and histone gene regions, as well as morphology, the new collections matched the ex-type strain of Cylindrocladium ilicicola. On the host and in culture, yellow to brownish-yellow perithecia were observed that did not strain red in 3 % KOH. Based on these results, C. ilicicola and its purported teleomorph, Ca. pyrochroa, were shown to represent two distinct species, as the latter has bright red perithecia that strain purple in KOH. A new combination, Ca. lauri, based on Tetracytum lauri, is subsequently proposed for C. ilicicola. Calonectria lauri is distinct from Ca. ilicicola, a pathogen commonly associated with Cylindrocladium black rot of peanut. Finally, Ca. canadiana is proposed as new name for Cy. canadiense, which is a nursery pathogen involved with root rot of several tree genera in Quebec, Canada.

In this study, we investigated the environmental factors associated with the establishment of invasive English holly (Hex aquifolium) and the spatiotemporal trajectories of its potential spread. We collected georeferenced presence and absence and demographic data of holly between 2011 and 2014 in Saint Edward State Park, Washington. We analyzed them through a spatially explicit framework that combines multiple logistic regression, cellular automata, and bivariate quadratic modeling. Results showed that the presence of holly is influenced by the proximity to evergreen coniferous vegetation and forest edge, distance to streams, forest structure, and slope direction. Our study confirmed that local environmental conditions, species characteristics, and vegetative and dispersal mechanisms play a significant role in determining the rate and success of holly establishment across the different phases of invasion. Invasive species management plans should consider both species characteristics and their habitat and the interactions among them when planning long-term strategies for control and eradication. [ABSTRACT FROM AUTHOR]

Copyright of Basic & Applied Ecology is the property of Urban & Fischer Verlag and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Seed dispersal by animals leads to plant genes, individuals and species flowing across the landscape, but this process has been seldom seen as the explicit result of structural or landscape connectivity., For two years, we studied avian seed dispersal of fleshy-fruited trees in a secondary forest of the northern Iberian Peninsula, considering the areas under the canopies of fruiting trees as hubs of seed deposition., Using graph-theory models, we set a spatially explicit network in a continuous landscape, with individual fruiting trees as nodes and expected frugivore movements as links between nodes. We calculated the contribution of each tree to network connectivity, finding strong inter-annual variability derived from tree properties (position, fruit crop and species)., Trees contributing the most to connectivity accumulated larger seed clumps under their canopies, demonstrating agreement between a network structural connectivity and the functional connectivity of seed dispersal flow. This pattern, however, is accentuated when the large-scale distribution of fruiting crops closely matches that of individual trees, suggesting between-year variation in resource tracking by avian frugivores., Our findings reveal connectivity to be an emerging property of plant-disperser systems, operating at the scale of individual fruiting plants, but contingent on the yearly, large-scale templates of fruiting crops. [ABSTRACT FROM AUTHOR]

Copyright of Journal of Forestry Faculty of Kastamonu University is the property of Kastamonu University and its content may not be copied or emailed to multiple sites or posted to a listserv without the copyright holder's express written permission. However, users may print, download, or email articles for individual use. This abstract may be abridged. No warranty is given about the accuracy of the copy. Users should refer to the original published version of the material for the full abstract. (Copyright applies to all Abstracts.)

Urban environments present an array of environmental conditions detrimental to the biology of trees. Two major problems include deicing salts, a common soil pollutant, and drought. One potential option for managing these environmental disorders may be through the application of commercially available biostimulants, as these products are reported to enhance a plant's resistance to environmental stresses. Trials used containerized stock of evergreen oak (Quercus ilex), holly (Ilex aquifolium), rowan (Sorbus aucuparia), and beech (Fagus sylvatica) to evaluate the effectiveness of seven commercially available biostimulants as drought and salt protectant compounds. Results conclude that none of the biostimulants evaluated in this study provided any significant degree of salt or drought damage protection compared to water-treated controls. [ABSTRACT FROM AUTHOR]

Seed dispersal at large scales strongly influences plant population dynamics. Still, ecologists have rarely measured seed dispersal at relevant scales, and the role of habitat types in affecting seed dispersal at long distances remains unexplored. We studied seed dispersal of Ilex aquifolium and Crataegus monogyna in northern Spain, hypothesizing that seeds would be recovered at higher rates and at longer distances (LDD) at habitats with fleshy-fruited trees, compared to habitats with other tree types or at open habitats. We tracked seeds in eight landscapes by enriching trees with 15N isotopes at the center of landscapes, and then detected 15N-marked seeds by sampling at distances of up to 700 m. We found that seeds arrive in greater densities and at longer distances in habitats with trees, particularly fleshy-fruited types, producing different LDD probabilities for each habitat. Results also show a disproportional arrival of seeds in habitats similar to those of mother plants, which should affect seed establishment and the genetic diversity of plant neighborhoods. Findings reveal the strong dependence of seed dispersal on the existing templates that guide the movements of avian dispersers in heterogeneous landscapes and also suggest that LDD above tree lines and beyond hard habitat edges can be difficult. [ABSTRACT FROM AUTHOR]

High-resolution pollen, macrofossil and charcoal data, combined with accelerator mass spectrometry 14C dating and multivariate analysis, were used to reconstruct Holocene vegetation and fire dynamics at Urio Quattrocchi, a small lake in the supra-mediterranean belt in the Nebrodi Mountains of Sicily (Italy). The data suggest that after 10 000 cal a BP increasing moisture availability supported closed forests with deciduous ( Quercus cerris, Fagus sylvatica and Fraxinus spp.) and evergreen ( Quercus ilex) species. Species-rich closed forest persisted until 6850 cal a BP, when Neolithic activities caused a forest decline and affected plant diversity. Secondary forest with abundant Ilex aquifolium recovered between 6650 and 6000 cal a BP, indicating moist conditions. From 5000 cal a BP, agriculture and pastoralism led to the currently fragmented landscape with sparse deciduous forests ( Quercus cerris). The study suggests that evergreen broadleaved species were more important at elevations above 1000 m a.s.l. before ca. 5000 cal a BP than subsequently, which might reflect less human impact or warmer-than-today climatic conditions between 10 000 and 5000 cal a BP. Despite land use since Neolithic times, deciduous supra-mediterranean forests were never completely displaced from the Nebrodi Mountains, because of favourable moist conditions that persisted throughout the Holocene. Reconstructed vegetation dynamics document the absence of any pronounced mid- or late-Holocene 'aridification' trend at the site, an issue which is controversially debated in Italy and the Mediterranean region. Copyright © 2012 John Wiley & Sons, Ltd. [ABSTRACT FROM AUTHOR]

Rapid range expansions are becoming more prevalent, especially as climate continues to change. The escape of ornamental plants within their native range represents a significant, but often overlooked component of this process. Few studies have focused on the role of ornamental plants in range expansions using molecular markers to identify the possibility of mixed native and cultivar populations. The purpose of the present study was to determine the genetic variation of a native woody plant with ornamental conspecifics at the edge of its distribution. We selected Ilex aquifolium L. (English holly) which grows naturally in Denmark but is spreading eastward in Scandinavia, possibly due to a combination of climate change and introduction of more frost-tolerant cultivars. We sampled 187 individuals from older and recently established populations, and cultivated I. aquifolium throughout Denmark, and compared them using nuclear SSR and AFLP. The overall results showed no structure or clustering of plants from the historical or the expanding range, or of wild or cultivated plants. The only clusters found were for a group of cultivated hybrid I. aquifolium. The samples represented four genetic groupings, indicating either hybridization between cultivated and wild I. aquifolium or replacement of the latter by cultivars. Thus, ornamental genotypes of I. aquifolium contribute to the northeastern range expansion of the species and eventual invasiveness within its native range. [ABSTRACT FROM AUTHOR]

Abstract: Dispersal limitations contribute to shaping plant distribution patterns and thus are significant for biodiversity conservation and urban ecology. In fleshy-fruited plants, for example, any preference of frugivorous birds affects dispersal capacities of certain fruit species. We conducted a removal experiment with fruits of Ilex aquifolium, a species that is currently expanding its range margin in northern Europe in response to climate change. The species is also a popular ornamental tree and naturalization has been observed in many parts of its range. Fruits of native I. aquifolium and of three cultivars were offered to birds at the expanding range margin in urban habitats in eastern Denmark. The four fruit types were removed at different rates and red fruits were preferred over a yellow cultivar. Small fruit diameter was positively related to fruit removal, and removal was faster under tree canopies compared with open habitats. The preference for red cultivars compared with native I. aquifolium may contribute to naturalization and potential invasion of garden escapes. Preferential foraging under closed canopies indicates trees and shrubs as recruitment foci for fleshy-fruited plants in urban landscapes. The results should be included in urban forestry and planting of potentially invasive ornamental species. [Copyright &y& Elsevier]

1. Plant distributions are dynamic but the role of plant-insect interactions in controlling range dynamics is not well understood. Enemy release, for example could facilitate plant range expansion under climate change. 2. We conducted a transplant experiment with the evergreen tree Ilex aquifolium L. in both the historical and the expanding range in Denmark to study possible effects of geographical position, small-scale distance, and plant types on presence and performance of the monophagous insect leaf-miner Phytomyza ilicis Curtis. 3. The leaf miner was present in the entire range of I. aquifolium in Denmark, and there were no differences in emergence success depending on geographical position. Small-scale distance to existing adult plants influenced the activity of the insect on the transplants, and oviposition density was negatively correlated with distance to adult plants. 4. Plant type had an effect on leaf miner feeding, oviposition and mining, and the native provenance of I. aquifolium supported higher densities than two cultivars. 5. There was no evidence that enemy release facilitates the current range expansion of I. aquifolium. [ABSTRACT FROM AUTHOR]

Abstract: Animal population density has been related to resource patch size through various hypotheses such as those derived from island biogeography and resource concentration theory. This theoretical framework can be also applied to plant–herbivore interactions, and it can be modified by the sex of the host-plant, and density-dependent relationships. Leaf-miners are specialised herbivores that leave distinct traces on infested leaves in the form of egg scars, mines, signs of predation and emergence holes. This allows the life cycle of the insect to be reconstructed and the success at the different stages to be estimated. The main stages of the leaf-miner Phytomyza ilicis were recorded in eleven populations of the evergreen host Ilex aquifolium in Denmark. Survival rates were calculated and related to population size, sex of the host plant, and egg and mine densities. Host population size was negatively related to leaf-miner prevalence, with larger egg and mine densities in small populations. Percentage of eggs hatching and developing into mines, and percentage of adult flies emerging from mines also differed among host populations, but were not related to population size or host cover. Feeding punctures left by adults were marginally more frequent on male plants, whereas egg scars and mines were more common on females. Overall survival rate from egg stage to adult emergence was higher on female plants. Egg density was negatively correlated with hatching, while mine density was positively correlated with emergence of the larvae. The inverse effects of host population size were not in line with predictions based on island biogeography and resource concentration theory. We discuss how a thorough knowledge of the immigration behaviour of this fly might help to understand the patterns found. [Copyright &y& Elsevier]

Habitat fragmentation increases seed dispersal limitation across the landscape and may also affect subsequent demographic stages such as seedling establishment. Thus, the development of adequate plans for forest restoration requires an understanding of mechanisms by which fragmentation hampers seed delivery to deforested areas and knowledge of how fragmentation affects the relationship between seed-deposition patterns and seedling establishment. We evaluated the dispersal and recruitment of two bird-dispersed, fleshy-fruited tree species (Crataegus monogyna and Ilex aquifolium ) in fragmented secondary forests of northern Spain. Forest fragmentation reduced the probability of seed deposition for both trees because of decreased availability of woody perches and fruit-rich neighborhoods for seed dispersers, rather than because of reductions in tree cover by itself. The effects of fragmentation went beyond effects on the dispersal stage in Crataegus because seedling establishment was proportional to the quantities of bird-dispersed seeds arriving at microsites. In contrast, postdispersal mortality in Ilex was so high that it obscured the seed-to-seedling transition. These results suggest that the effects of fragmentation are not necessarily consistent across stages of recruitment across species. Habitat management seeking to overcome barriers to forest recovery must include the preservation, and even the planting, of fleshy-fruited trees in the unforested matrix as a measure to encourage frugivorous birds to enter into open and degraded areas. An integrative management strategy should also explicitly consider seed-survival expectancies at microhabitats to preserve plant-population dynamics and community structure in fragmented landscapes. [ABSTRACT FROM AUTHOR]

The article discusses the study regarding the combination of local- and large-scale models to predict the distributions of invasive plant species. It states that habitat distribution models (HMDs) can accurately predict potential distributions and can greatly benefit the monitoring and control of nonnative invaders. It presents several study species such as the geranium robertianum, a biennial herb, hedera helix, an evergreen vine, and ilex aquifolium, an evergreen tree.

An approach integrating phytosociological and stand structure surveys with the predictive modelling of species distribution was applied to analyse the spatial distribution and dynamics of the Apennine beech forests with Taxus and Ilex, a high conservation priority forest habitat in Europe. The homogeneity of the habitat was tested trough a Mann-Whitney test between beech woods with Taxus and those with Ilex with respect to climatic, topographic, structural and environmental parameters: the former have proven to be more microthermic, mesophilous and characterised by a closer canopy. Five statistical models were compared to analyse the relationship between bioclimatic parameters and Taxus and Ilex spatial distribution: Regression Tree Analysis, the most efficient model, has shown that the distribution of Taxus is influenced by precipitation variables, while Ilex is mainly influenced by temperature variables. This model highlighted that Ilex has a potential area that surrounds, at lower altitudes, that of Taxus. A stepwise multiple regression analysis has been applied to identify the factors influencing the regeneration of the two species: beside climatic parameters, Taxus regeneration is negatively influenced by soil nitrate concentration (an indicator of livestock disturbance) while Ilex is negatively influenced by beech forest cover. Traditional management practices seem to have an effect on the regeneration of the two species: frequent cuts favour the regeneration of Ilex, reducing the forest cover and allowing more light penetration, while Taxus, less resistant to grazing livestock, is confined to more inaccessible places. The multiple approach has proven to be useful for the elaboration of two differentiated conservation strategies for the two beech forest types. [ABSTRACT FROM AUTHOR]

The objective of this study was to examine antibacterial, antifungal, and antimycobacterial properties of Ilex aquifolium L. (Aquifoliaceae) growing in Turkey. The ethanol, ethyl acetate, chloroform, and n-hexane extracts prepared from the leaves of I. aquifolium were tested against Escherichia coli, Staphylococcus aureus, Pseudomonas aeruginosa, Enterobacter aerogenes, Proteus vulgaris, Salmonella typhimurium, and Candida albicans for antibacterial and antifungal evaluation using the microdilution broth susceptibility assay. In addition, antimycobacterial activity of the crude extracts of I. aquifolium was evaluated by microplate Alamar blue assay. The results showed that the extracts tested, except n-hexane, possessed moderate antibacterial and antifungal activity varying from 62.5 to 250 μg/mL. On the other hand, the ethanol extract of the leaves exhibited a minimum inhibitory concentration value (MIC) against Mycobacterium tuberculosis H37Ra strain of 200 μg/mL. [ABSTRACT FROM AUTHOR]

High infection rates of European holly ( Ilex aquifolium) feeder roots by an unknown root-knot nematode were found in a holly forest at Arévalo de la Sierra (Soria province) in northern Spain. Holly trees infected by the root-knot nematode showed some decline and low growth. Infected feeder roots were distorted and showed numerous root galls of large (8–10 mm) to moderate (2–3 mm) size. Morphometry, esterase and malate dehydrogenase electrophoretic phenotypes and phylogenetic trees of sequences within the ribosomal DNA (rDNA) demonstrated that this nematode species differs clearly from other previously described root-knot nematodes. Studies of host-parasite relationships showed a typical susceptible reaction in naturally infected European holly plants, but did not reproduce on a number of cultivated plants, including tomato, grapevine, princess-tree and olive. The species is described here, illustrated and named as Meloidogyne silvestris n. sp. The new root-knot nematode can be morphologically distinguished from other Meloidogyne spp. by: (i) roundish perineal pattern, dorsal arch low, with fine, sinuous cuticle striae, lateral fields faintly visible; (ii) female excretory pore level with stylet knobs, or just anterior to them, EP/ST ratio about 0·8; (iii) second-stage juveniles with hemizonid located 1 to 2 annuli anterior to excretory pore and short, sub-digitate tail; and (iv) males with lateral fields composed of four incisures, with areolated outer bands. Phylogenetic trees derived from maximum parsimony analysis based on 18S, ITS1-5·8S-ITS2 and D2–D3 of 28S rDNA showed that M. silvestris n. sp. can be differentiated from all described root-knot nematode species, and it is clearly separated from other species with resemblance in morphology, such as M. ardenensis, M. dunensis and M. lusitanica. [ABSTRACT FROM AUTHOR]

Abstract: European Holly (Ilex aquifolium L.) was used to study the impact of one short (28day) ozone fumigation episode on leaf production, leaf loss and stomatal conductance (g s), in order to explore potential longer term effects over 3 growing seasons. Young I. aquifolium plants received an episode of either charcoal-filtered air or charcoal-filtered air with 70nll−1 O3 added for 7hd−1 over a 28day period from June 15th 1996, then placed into ambient environment, Stoke-on-Trent, U.K. Data were collected per leaf cohort over the next three growing seasons. Ozone exposure significantly increased leaf loss and stomatal conductance and reduced leaf production over all subsequent seasons. Impact of the initial ozone stress was still detected in leaves that had no direct experimental ozone exposure. This study has shown the potential of ozone to introduce long-term phenological perturbations into ecosystems by influencing productivity over a number of seasons. [Copyright &y& Elsevier]

Abstract: European Holly (Ilex aquifolium) received either charcoal-filtered air (CFA) or CFA with 70nll−1 ozone added for 7h day−1 over a 28 day period. Plants were then transferred into cooling incubators for hardening (4°C day/2°C night; day length 12h) for 7 days and then to the frosting stage (2°C day and −5, −10 or −15°C night) for 4 days. The plants were then placed in ambient conditions. Treatment produced significant differences in chlorophyll fluorescence data. Stomatal conductance was significantly higher for the ozone treatments though both showed a general decline over all temperature regimes. Ozone also significantly increased electrolyte leakage and reduced winter survival. These results show that ambient concentrations of ozone can reduce the tolerance of I. aquifolium to freezing stress, which may have serious implications for its establishment and survival. [Copyright &y& Elsevier]

The aim of this study is to evaluate the recruitment possibilities of holly ( Ilex aquifolium L.) populations under Pinus sylvestris plantations in the mountains of Central Spain. Population recruitment of holly under P. sylvestris L. plantations was studied at two localities. We sampled holly seed rain, seed bank, and seedling emergence and survival (of both emerged and planted seedlings) in both localities. Seed germination was analysed by randomly sowing Ilex seeds and their subsequent recollection and analysis over the following 3 years (only in one locality). Seed rain, seed bank and emerged seedling densities did not differ between localities. Seed bank density was between 10 and 20 seeds m−2, considerably higher than the observed seed rain (0.4–1.2 seeds m−2), and also higher than the emerged seedling density (0–4 seedlings m−2). But Ilex is not very efficient in germinating under pine forests (29.1% germination after 3 years). This may indicate a seed accumulation process of at least 5 years. Seedling survival for the first year differed among the studied sites (50–60 vs. 17%). Nevertheless these survival rates are higher than those found for the same seedling populations in different forest habitats (not Scots pine forests) from near locations. Differences in summer water stress between the study sites are proposed as the main cause of the observed differences in seedling survival. It is concluded that P. sylvestris forests may provide one of the best regeneration habitats for holly in the Mediterranean area, where this species is close to the Southern limit of its distribution. [ABSTRACT FROM AUTHOR]

Old-growth deciduous forests in western Europe, for the most part, consist of small tracts that often may be atypical due to human disturbance, poor soil productivity or inaccessibility. In addition, very little information on tree age distributions, structural heterogeneity and tree spatial patterns appears to be available for west-European forests. Characterization of the structural features of tree populations in these old-growth stands can provide the basis to design conservation plans and also inform on how present forests might look in the absence of human interference. Four old-growth stands in a deciduous forest in the Cantabrian lowlands, northern Spain, were surveyed to determine forest structure and spatial patterns. Live and dead trees were identified, measured and mapped, and live trees were cored for age estimation. Structural heterogeneity was analyzed by means of the spatial autocorrelation of tree diameter, height and age, and the uni- and bivariate spatial patterns of trees were analyzed. The dominant species, Fagus sylvatica and Quercus robur, showed reverse-J shaped size distributions but discontinuous age distributions, with maximum ages of 255–270 yr. Tree ages suggested that the forest was largely modified by past changes in forest-use, especially by temporal variation in grazing intensity. Spatial autocorrelation revealed that former parkland stands were heterogeneous with respect to tree height only, while high forest stands were composed of patches of even-aged and even-sized trees. Young trees were clumped at varying distances and establishment occurred preferentially in canopy gaps, except for Ilex aquifolium that mainly occurred beneath mature Quercus trees. Surviving trees became less intensely clumped in the dominant species, and more strongly clumped in understorey ones, which may have been due to the effects of intraspecific competition and of canopy trees on tree survival, respectively. The spatial associations between species varied within the forest, probably as a consequence of specific establishment preferences and competitive interactions. [ABSTRACT FROM AUTHOR]

Abstract: Seedling emergence and survival was monitored over 3 years in a holly woodland and the surrounding habitats, located in Central Spain. Ten random quadrats were established in each of the following microhabitats: inside the closed holly woodland, in small canopy gaps of this woodland, at the woodland edge, in the adjacent open grassland, under isolated fleshy-fruited shrubs in the grassland and in an adjacent oak woodland. Seedling emergence was maximum in closed holly woodland, from 7 to 51 seedlings m−2, and in the gaps, from 3 to 40 seedlings m−2. At the edge and under the shrubs emergence was lower than in the holly woodland (between 1 and 4 seedlings m−2), while no germination was detected in the grassland microhabitat. Under the oak woodland canopy, seedling emergence was approx. 4 seedlings m−2. Survival after the first year following germination was low inside the holly woodland, from 0 to 2% under the closed holly canopy and from 0 to 8% in the canopy gap. Survival was higher at the edge (between 25 and 54%) and under the oak woodland (27%), while under the shrubs the mortality showed a high interannual variability (from 9 to 80%). Mortality inside the holly woodland was due to the combination of a very low light availability and a high soil disturbance, the establishment in the gaps being slightly better than under the closed canopy. The oak woodland presents better conditions for survival, due to higher light levels, and lower disturbance episodes. At the edge and under the shrubs greater light levels, a higher incidence of invertebrate herbivory and lower edaphic humidity were present. These holly populations show patchy regeneration dynamics, with an apparent propagule-seedling conflict, due to the uncoupling of emergence and survival, resulting in a low net annual incorporation. Regeneration within the holly woodland is very limited and vegetative self-maintenance is the most viable alternative means. However, holly appears to exploit the forest ecotones and shrub invasion through sexual propagation of a young population away from parental influence. This work deepens the knowledge of the recruitment probabilities of these singular patchy woods, helping to develop good land management policies. This management should be based on the combination of the increase in self-maintenance probabilities of the previously established woodlands, and the promotion of those natural processes of population propagation documented here. [Copyright &y& Elsevier]

High mortality rates of bare-root stock can occasionally occur post-planting due to poor plant vitality at the time of planting. Consequently, physiological tests of plant vitality, such as stem electrolyte leakage, root growth potential (RGP), and chlorophyll fluorescence, are valuable because of their ability to identify low-vigor or damaged plants that will perform poorly when planted into the landscape. The survival, growth, and foliar damage of three tree species commonly used in landscape plantings was accurately predicted by stem electrolyte leakage, RGP, and chlorophyll fluorescence 17 weeks post-planting under field conditions following freezing damage. Of the three physiological tests, correlation of field performance with stem electrolyte leakage had the highest mean r² values, which, based on results of this investigation, was a marginally better predictor of future plant performance compared to chlorophyll fluorescence and RGP. Chlorophyll fluorescence measurements taken from woody tissue of birch (Betula spp.), a deciduous tree species, were highly predictive of subsequent survival, foliar damage, and height increment 17 weeks post-planting, indicating that chlorophyll fluorescence may have applications as a predictor of plant vitality and future growth in deciduous ornamental trees. The practical advantages and disadvantages offered by each plant vitality test to professionals involved in urban tree management are discussed. [ABSTRACT FROM AUTHOR]

Abstract Variation in the chloroplast genome of Ilex aquifolium (English holly), a dioecious evergreen tree native to south, west and central Europe, was analysed using polymerase chain reaction–restriction fragment length polymorphisms (PCR-RFLPs) and microsatellites. Differentiation between populations was high (G [sub ST] = 0.595) and evidence for phylogeographical structure was detected (N [sub ST] = 0.697, significantly higher than G [sub ST] ). Two chloroplast lineages were inferred originating from putative glacial refugia in southern Europe (Iberia, Italy and possibly the Balkans). The G [sub ST] value was higher than reported for endozoochorous hermaphrodite species and for anemochorous dioecious species investigated over a similar geographical scale. It appears that dioecy has contributed to strong differentiation between refugia and that this has been maintained following postglacial recolonization as a result of limited seed flow. Palynological records for I. aquifolium are poor, thus these results give an important insight into patterns of glacial isolation and postglacial recolonization of this species. [ABSTRACT FROM AUTHOR]