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Ajouter le résultat dans votre panierThe variable responses of bracken fronds to control treatments on Great Britain / Mike G. Le Duc in Annals of Botany, 85 (B) (03/2000)
Titre : The variable responses of bracken fronds to control treatments on Great Britain Type de document : Électronique Auteurs : Mike G. Le Duc ; Mike G. Le Duc ; Robin J. Pakeman ; P. D. Putwain ; Rob H. Marrs Année de publication : 2000 Article en page(s) : 17-29 Langues : Anglais (eng) Catégories : [CBNPMP-Géographique] Grande Bretagne
[CBNPMP-Thématique] Ptéridophytes, fougèresMots-clés : Pteridium aquilinum Résumé : We describe six experiments set up at four regional locations in Great Britain, in 1993 and 1994, to examine the impact of control treatments on bracken and associated vegetation. Present discussion is limited to the effects of treatments on bracken frond variables (density, length and dry mass). These variables would be used by a land manager to judge the extent of infestation and the efficacy of control methods. Results of statistical analyses are reported for the period 1994 to 1998, inclusive. The treatments showed great variability in effectiveness between both sites and years. Great inter-regional differences were seen, but stands at sites within a short distance of each other also varied in their response to treatment. Meso- and micro-climatic differences are suggested as possible causes, together with stand growth phase and genetic effects. The most effective treatments in the short-term were found to be combinations of cutting and herbicide spraying, applied once. Annual cutting usually gave a better result in the longer term. All treatments had greatly improved effects when combined with a follow-up application of herbicide several years after commencement. A number of recommendations are given for management, such as best methods for short- and long-term results. Systematic monitoring is urged as changes in frond density, for example, may reveal the extent of the problem for control at a particular site. Lien pérenne : DOI : 10.1006/anbo.1999.1052 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142044
in Annals of Botany > 85 (B) (03/2000) . - 17-29Le Duc, Mike G., Le Duc, Mike G., Pakeman, Robin J., Putwain, P. D., Marrs, Rob H. 2000 The variable responses of bracken fronds to control treatments on Great Britain. Annals of Botany, 85(B): 17-29.Documents numériques
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Titre : Follow-up methods for bracken control following an initial glyphosate application : the use of weed wiping, cutting and reseeding Type de document : Électronique Auteurs : P Petrov ; Rob H. Marrs Année de publication : 2000 Article en page(s) : 31-35 Langues : Anglais (eng) Catégories : [CBNPMP-Géographique] Bulgarie
[CBNPMP-Thématique] Ptéridophytes, fougèresMots-clés : Pteridium aquilinum (L.) Kuhn, 1879 Résumé : Between 1990 and 1996 a range of follow-up strategies were applied to a permanent meadow in Bulgaria infested with bracken (Pteridium aquilinum), which was recovering after initial control using glyphosate. The initial glyphosate treatment (4·3 kg ha-1) reduced both the bracken infestation and the underlying weedy vegetation, and facilitated the recovery of pasture species. However, there was rapid bracken recovery within 5 years where no follow-up treatment was applied. Cutting twice yearly slowed recovery, but the most effective treatments were where (1) there had been a single follow-up weed wiping application of glyphosate plus cutting twice yearly, or (2) where Festuca rubra and Vicia cassubica were sown. Reseeding on its own or combined with cutting twice yearly provided good bracken control and a high forage quality over the 5 year period. Lien pérenne : DOI : 10.1006/anbo.1999.1083 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142045
in Annals of Botany > 85 (B) (03/2000) . - 31-35Petrov, P, Marrs, Rob H. 2000 Follow-up methods for bracken control following an initial glyphosate application : the use of weed wiping, cutting and reseeding. Annals of Botany, 85(B): 31-35.Documents numériques
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Titre : Bracken distribution in Great Britain : strategies for its control and the sustainable management of marginal land Type de document : Électronique Auteurs : Robin J. Pakeman ; Mike G. Le Duc ; Rob H. Marrs Année de publication : 2000 Article en page(s) : 37-46 Langues : Anglais (eng) Catégories : [CBNPMP-Géographique] Grande Bretagne
[CBNPMP-Thématique] Ptéridophytes, fougèresMots-clés : Pteridium aquilinum (L.) Kuhn, 1879 Résumé : Bracken is often perceived as a widespread and increasing land management problem. The pollen record of a wide range of sites in Great Britain suggests that the current abundance of bracken is less than or, at worst, equivalent to maximum historical levels. Recently gathered data also suggest that bracken cover is declining. Results of risk assessments of land use change, and experimental and modelling investigations into the effects of climate change are synthesized. This synthesis suggests that there is the potential for increased bracken dominance in northern Britain, spread into new areas at high altitudes, and possible spread into areas with reduced grazing. However, this must be set against any changes in the extent of other vegetation types at the expense of bracken. There is now a long history of bracken control, both in Great Britain and globally. Conventional methods of control (cutting, asulam application) are well understood, but many control attempts do not result in long-term success, as control is often not followed by aftercare. Bracken control is just one part of the process to ensure a sustainable use of resources and to maintain biodiversity. A coherent strategy for bracken control is put forward, a necessary part of which includes the restoration of vegetation and subsequent land management which takes into account an understanding of bracken ecology. Lien pérenne : DOI : 10.1006/anbo.1999.1053 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142046
in Annals of Botany > 85 (B) (03/2000) . - 37-46Pakeman, Robin J., Le Duc, Mike G., Marrs, Rob H. 2000 Bracken distribution in Great Britain : strategies for its control and the sustainable management of marginal land. Annals of Botany, 85(B): 37-46.Documents numériques
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Titre : The ecology of bracken : its role in succession and implications for control Type de document : Électronique Auteurs : Rob H. Marrs ; Mike G. Le Duc ; RJ Mitchell ; D Goddard ; S Paterson ; Robin J. Pakeman Année de publication : 2000 Article en page(s) : 3-15 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Ptéridophytes, fougères Mots-clés : Pteridium aquilinum Résumé : Bracken (Pteridium) holds a pivotal role in succession, usually occurring in sequence between plagio-climax communities such as heathland and woodland. It is at this interface that bracken causes problems for man, as the subseral communities are more valuable for agricultural use and most have a greater conservation value than brackendominated ones (there are a few exceptions). This paper examines the role of bracken in a series of successional trajectories on lowland heaths; there is evidence that bracken occurs in a trajectory towards birch woodland in Dorset. Whether the bracken stage is an intermediate stage towards woodland or acts as a 'mini-climax' in itself remains to be demonstrated. Thereafter, the impact of bracken control on vegetation development is examined from two successional viewpoints, succession reversal towards the early successional communities, and successional accelerations towards woodland. A range of examples is provided from: (1) lowland heaths in England; (2) moorlands in upland Britain where bracken has been treated with asulam; and (3) in North Wales where attempts have been made to restock woodlands. Lien pérenne : DOI : 10.1006/anbo.1999.1054 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142047
in Annals of Botany > 85 (B) (03/2000) . - 3-15Marrs, Rob H., Le Duc, Mike G., Mitchell, RJ, Goddard, D, Paterson, S, Pakeman, Robin J. 2000 The ecology of bracken : its role in succession and implications for control. Annals of Botany, 85(B): 3-15.Documents numériques
Article (2000)URL
Titre : Modelling the effects of patch size on vegetation dynamics : bracken [Pteridium aquilium (L.) Kuhn] under grazing Type de document : Électronique Auteurs : Colin PD Birch ; Nicolas Vuichard ; Ben R Werkman Année de publication : 2000 Article en page(s) : 63-76 Langues : Anglais (eng) Catégories : [CBNPMP-Thématique] Ptéridophytes, fougères Mots-clés : Pteridium aquilinum Calluna vulgaris (L.) Hull Résumé : A new spatial simulation model of vegetation dynamics, called ‘VegeTate’, was applied to relationships between expansion of bracken (Pteridium aquilinum (L.) Kuhn) patches and grazing. VegeTate simulates multispecies dynamics within each cell of its grid, including localized apparent competition mediated by grazing and trampling. It can be parameterized to simulate various plant communities and species, includes seasonality and uses a hexagonal grid. Dynamics of individual bracken patches in grassland, and of heathland initially containing sparse grass and bracken were simulated. Mixtures of grass and bracken formed mosaics, in which locally high grass densities were associated with low standing mass and high grazing intensity, whereas high bracken densities were associated with high standing mass and low grazing intensity. Control of bracken by grazing depended on the impact of trampling. In simulations, small bracken patches occupying one or a few cells could be controlled by grazing, but not the expansion of large patches. In a sensitivity analysis, this phenomenon was reproduced after substantial changes in parameter values and environmental conditions, suggesting that it should be observable in the field. Interaction between patch size and grazing impact strongly influenced the spatial dynamics of simulated vegetation. The size of bracken patches became bimodal, so that most of the area of bracken was within a few large patches. Both spatial and temporal vegetation dynamics became non-linear. These results are consistent with observations that some bracken patches contain several genets and some genets occupy several patches. The hexagonal grid and trampling were important factors in the simulation results. Lien pérenne : DOI : 10.1093/oxfordjournals.aob.a010319 Permalink : https://biblio.cbnpmp.fr/index.php?lvl=notice_display&id=142048
in Annals of Botany > 85 (B) (03/2000) . - 63-76Birch, Colin PD, Vuichard, Nicolas, Werkman, Ben R 2000 Modelling the effects of patch size on vegetation dynamics : bracken [Pteridium aquilium (L.) Kuhn] under grazing. Annals of Botany, 85(B): 63-76.Documents numériques
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