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This account presents information on all aspects of the biology of Salvia pratensis L. (Meadow Clary) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.Salvia pratensis is an erect, rosette‐forming, perennial herb with a broad native distribution covering much of Europe—from the British Isles, Spain and Morocco in the west, across Europe into Asia, as far east as the Urals. In the British Isles, the species is nationally scarce, confined to a few south‐ to west‐facing sites with calcareous soils in Southern England and one site in Wales. It is predominately found in unimproved pasture, hay meadows and grassy verges, but can occur on the fringes of scrub or woodland. Although the species is abundant in central Europe, changes to land management since the mid‐20th century have resulted in fragmented and threatened populations in several European countries. It is cultivated as an ornamental, as is S. × sylvestris, the hybrid with S. nemorosa.Populations are typically gynodioecious, having both female (male‐sterile) and hermaphrodite individuals at variable proportions. The species has a mixed mating system and is self‐compatible via insect pollination, but predominantly outcrosses. Honeybees and bumblebees are abundant pollinators, but a diverse range of bee species and other insect species visit S. pratensis flowers. Inbreeding depression has been documented, presenting a conservation concern for small, fragmented populations.The species is the focus of conservation efforts and has been reintroduced to sites where it had become locally extinct in Britain. To sustain favourable habitat, site management should maintain low soil nutrient levels, and prevent scrub encroachment and the dominance of coarse grasses. The removal of sward by hay cutting or grazing after plants have flowered and set seed is advised, in addition to maintaining a degree of disturbance to provide bare patches of soil for seedling recruitment. [ABSTRACT FROM AUTHOR]

1. Leaf trait relationships of native and exotic invasive species from a range of habitats were compared to assess consistency across habitats and the role of disturbance. 2. One hundred and twenty-two native and exotic species were sampled in five habitats in eastern Australia. Specific leaf area, foliar nitrogen ( Nmass), assimilation rate ( Amass) and dark respiration ( Rmass) were measured for each species. Plants were classified into four types: native undisturbed, native disturbed, exotic invasive undisturbed and exotic invasive disturbed. 3. All traits were positively correlated and slopes were homogeneous within habitats. Significant differences between plant types in slope elevation were found in only two of 18 cases. There were significant shifts in group means along a common slope between plant types within habitats. These shifts were associated with disturbed vs. undisturbed areas, with plant types from disturbed areas having higher trait values. 4. Synthesis. Exotic invasive and native species do not have fundamentally different carbon capture strategies. The carbon capture strategy of a species is strongly associated with disturbance, with species from disturbed sites having traits that confer capacity for fast growth. Thus, differences between exotic invasives and natives may reflect differences in the environmental conditions of the sites where they occur rather than differences between exotic invasives and natives per se. [ABSTRACT FROM AUTHOR]

1. This account presents information on all aspects of the biology of Primula vulgaris Huds. (Primrose) that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characteristics, herbivores and disease, history and conservation. 2. Primula vulgaris is a native perennial herb with a very wide distribution in the British Isles. In many lowland areas it is essentially a plant of woodlands and hedgerows, although in the west it can occur abundantly in grasslands and other communities such as heaths. In northern and western Britain and Ireland, it may be frequent in open and even exposed habitats. Its distribution is linked with soil moisture and atmospheric humidity. It is shade tolerant, but it flowers most profusely in canopy gaps. 3. Primula vulgaris is a rosette hemicryptophyte that reproduces mainly through seeds. Vegetative spread is restricted and only occurs within very short distances from the mother plant through the production of lateral rosettes. Although individual rosettes may die, plants are relatively long-lived (life expectancy of a newborn individual: 48.3 years). The mean age at first flowering was 20 months. 4. Pollination is mainly by bumblebees and other bees, but other long-tongued pollinators including syrphids, bee-flies and even butterflies may be locally important. P. vulgaris is an obligate outbreeder, with two genetically determined self-incompatible morphs (‘pin’ and ‘thrum’). A third morph (‘homostyle’ or ‘long homostyle’), with a stigma like that of pin but anthers like that of thrum, has been found in Somerset and North Dorset. In years when pollinators are scarce, homostyles have higher reproductive success than pins and thrums, suggesting that reproductive assurance could have had a profound effect on the evolution of homostyly in P. vulgaris. 5. Seeds are dispersed by ants and rodents. Dispersal is usually restricted to a few centimetres or decimetres from maternal plants, resulting in significant fine-scale spatial genetic structure and small neighbourhood sizes. Pollen flow, on the other hand, is more extensive, but still limited to a few metres from paternal plants. 6. Populations of P. vulgaris have not changed markedly during the last century in most parts of Britain and Ireland and it is not threatened with extinction nationally. However, there is evidence that Primroses were formerly more widespread and have decreased with the decline of coppicing and pollarding. In East Anglia, woodland populations have declined greatly in response to a series of hot, dry summers since 1970. Small, isolated populations of P. vulgaris often show reduced reproductive success, potentially affecting their long-term survival. Preservation of local habitat conditions and restoration of gene flow among populations are required to maintain viable populations of P. vulgaris in the long term. [ABSTRACT FROM AUTHOR]

1. This account presents information on all aspects of the biology of Primula elatior that are relevant to understanding its ecological characteristics and behaviour. The main topics are presented within the standard framework of the Biological Flora of the British Isles: distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history, and conservation. 2. Primula elatior is a native perennial herb, within a compact area in the British Isles, in ancient woods and copses on the chalky boulder clay in East Anglia, where it is abundant locally although scarce nationally. British material is ssp. elatior, which extends across much of Europe, becoming rarer towards the south. 3. Primula elatior is a shade tolerant species, but only flowers in profusion in the increased light levels following tree felling in traditionally coppiced woods. It is confined to an area of the British Isles where the soils are seasonally waterlogged and ill-aerated, and is very tolerant of the toxic levels of ferrous iron which accumulate in the surface horizons in the spring months. It has a poorly developed drought tolerance. 4. An early flowering plant, P. elatior is an insect-pollinated obligate outbreeder, with two self-incompatible morphs (pin and thrum). The low colonizing ability of this ancient woodland species can be attributed to both seed dispersal and seedling recruitment limitation. 5. There has been a steady reduction in the density of P. elatior in woodland sites during the past centuries. However, there has been little change in the 10-km distribution in the British Isles. Studies of populations involve three groups of factors: genetic variation, environmental changes and population structure. Potentially these factors have a greater effect on small and isolated populations than on large and integrated ones. There is no evidence that the species suffers from a loss of genetic diversity in the smaller populations. Primula elatior seems to have a relatively high level of genetic diversity that is maintained despite a fragmented distribution. 6. Within its restricted distribution area P. elatior replaces P. vulgaris completely. At the margins of their distributions the two species occur together in a number of woodland sites, providing the opportunity for hybridization. As they are highly interfertile, hybridization is restricted mainly by differences in their habitat preferences. The hybrid P. vulgaris ×  P. elatior =  P. ×  digenea is fertile and gives rise to hybrid swarms which are found in all British sites where both parents occur together. 7. Changes in climate, woodland management practices and intensities of deer grazing, especially by Fallow deer ( Dama dama), are likely to have a major effect on populations of P. elatior. Since the species colonizes new or secondary woodlands very slowly, management should focus on the conservation of ancient semi-natural woodlands. [ABSTRACT FROM AUTHOR]

The article discusses some comparative studies on photosynthesis, respiration and water relations of 10 arid zone and two semi-arid zone plants under winter and late summer climatic conditions. Data on carbon dioxide exchange and water relations were obtained for eight arid and two semi-arid zone native plant species of Western Australia. In late summer, all species showed a positive carbon dioxide balance which indicates that there is sufficient soil water in deeper soil layers. All the species tested possess a high heat resistance and are well suited to their natural environment.

This article presents a study which investigated the plant patterns of different seasons in two stands of mallee vegetation in Australia. A brief background on the study areas, a review of previous related literature and a description of the study's methodology are provided. The study found that mallee vegetation is dominated by tall shrubby individuals of Eucalyptus and in many areas it can be divided into mallee thickets and large openings. The phytosociological patterns of stands based on seasons are explored.

The article focuses on a study which investigates some aspects of the interaction of plants, rabbits and seabirds on nine islands in South Africa. One of the most important results of the study is the intense competition between plants and animals for the space available on the islands, particularly on breeding areas. Rabbits, which are very rare on the African mainland because of the abundance of predators, exert a profound influence on the island vegetation, while bush-nesting birds are linked with the start and end of the rabbit plagiosphere, but are excluded from the middle phases which are occupied by ground-nesting birds. Moreover, branch conformation of shrubs has an important bearing on selection of nest site by cormorants.

The article discusses the physiology of xerophytic plants in Australia. It cites a study which has shown that succulent plants have a low intensity of transpiration while hard-leaved xerophytes and those xerophytes with semi-succulent leaves transpired more than mesophytic leaves under high tension of meteorological factors. In addition, the study found that plants subjected to permanent wilting possess a greater number of stomata per unit area than those that develop in an unwilted condition. Data on stomatal size and stomatal index are also provided.