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This account presents information on all aspects of the biology of Geranium pratense L. (Meadow Crane's‐Bill). The main topics are presented within the standard framework of the Biological Flora of Britain and Ireland : distribution, habitat, communities, responses to biotic factors, responses to environment, structure and physiology, phenology, floral and seed characters, herbivores and disease, history and conservation.Geranium pratense is a perennial gynodioecious forb of neutral grassland. In Britain and Ireland, it is particularly abundant on roadside verges, railway embankments, the margins of watercourses and woodland rides. It is generally intolerant of grazing and is absent or scarce in livestock‐grazed grassland. Geranium pratense is widespread in England, Wales and Scotland but is scarce in Ireland. It has an extensive native range in Europe and Asia, extending eastwards to Russia, north‐western China and Mongolia. It has been widely introduced to new sites within its native range and has been introduced to Canada, the USA and New Zealand.Geranium pratense usually occurs on free‐draining soils but also infrequently where drainage is impeded. The soils are often nutrient‐rich and weakly acidic to weakly alkaline. The underlying geology is usually non‐acidic sedimentary rocks or superficial deposits.Geranium pratense is protandrous and is pollinated by various insects of the orders Hymenoptera, Diptera and Lepidoptera, particularly bumblebees, solitary bees, hoverflies and butterflies. Eleven species of phytophagous insect have been recorded on G. pratense in Britain and Ireland.Geranium pratense has little or no capacity for vegetative spread. Primary seed dispersal is ballistic and seeds may be flung over distances of up to several metres. The species has a transient seed bank, that is germination typically takes place in the winter and spring after seed production, after the physically dormant seeds have become permeable. Seedling establishment is higher in vegetation‐free gaps than in undisturbed grassland vegetation.There has been no significant change in its distribution between the late 1950s and 2019, although since 2000, it has expanded its range, mainly via introductions, in northern and western Scotland, west Wales and in Ireland. Alien sites have increased markedly since the 1960s due to introductions from wildflower seed sowing and spread from gardens. [ABSTRACT FROM AUTHOR]

There is increasing evidence that farmers in many areas are achieving below maximum yields due to insufficient pollination. Practical and effective approaches are needed to maintain wild pollinator populations within agroecosystems so they can deliver critical pollination services that underpin crop production. We established nesting and wildflower habitat interventions in 24 UK apple orchards and measured effects on flower‐visiting insects and the pollination they provide, exploring how this was affected by landscape context. We quantified the extent of pollination deficits and assessed whether the management of wild pollinators can reduce deficits and deliver improved outcomes for growers over 3 years. Wildflower interventions increased solitary bee numbers visiting apple flowers by over 20%, but there was no effect of nesting interventions. Other pollinator groups were influenced by both local and landscape‐scale factors, with bumblebees and hoverflies responding to the relative proportion of semi‐natural habitat at larger spatial scales (1000 m), while honeybees and other flies responded at 500 m or less. By improving fruit number and quality, pollinators contributed more than £16 k per hectare. However, deficits (where maximum potential was not being reached due to a lack of pollination) were recorded and the extent of these varied across orchards, and from year to year, with a 22% deficit in output in the worst (equivalent to ~£14 k/ha) compared to less than 3% (equivalent to ~£2 k/ha) in the best year. Although no direct effect of our habitat interventions on deficits in gross output was observed, initial fruit set and seed set deficits were reduced by abundant bumblebees, and orchards with a greater abundance of solitary bees saw lower deficits in fruit size. The abundance of pollinators in apple orchards is influenced by different local and landscape factors that interact and vary between years. Consequently, pollination, and the extent of economic output deficits, also vary between orchards and years. We highlight how approaches, including establishing wildflower areas and optimizing the ratio of cropped and non‐cropped habitats can increase the abundance of key apple pollinators and improve outcomes for growers. [ABSTRACT FROM AUTHOR]

Aphidophagous hoverflies (Diptera, Syrphidae, Syrphinae) are common flower visitors and aphid predators in a range of flowering plants, including fruit crops. Here, we investigate whether aphid prey DNA can be detected in the gut contents of hoverfly larvae from a commercial strawberry field as a proof of concept that a molecular approach can be used to measure agricultural biocontrol. We used high-throughput sequencing (HTS) to target insect DNA and compared the resulting data to reference databases containing aphid and hoverfly DNA sequences. We explored what impact incorporating wildflowers within polythene-clad tunnels may have on aphid DNA detection rates in hoverfly larvae. In a randomized block experiment, coriander (Coriandrum sativum), field forget-me-not (Myosotis arvensis) and corn mint (Mentha arvensis) plants were inserted in rows of strawberries. Their effect on aphid DNA detection rates was assessed. Aphid DNA was found in 55 of 149 specimens (37%) validating the method in principle for measuring agricultural services provided by hoverflies. Interestingly, detection rates were higher near plots with forget-me-not than plots with coriander, though detection rates in control plots did not differ significantly from either wildflower species. These findings confirm that hoverflies predate aphids in UK strawberry fields, and that HTS is a viable method of identifying aphid DNA in predatory hoverflies. We comment on the need for further method development to narrow down identifications of both predator and prey. We furthermore provide some evidence that there is an effect of intercropping strawberry crops with wildflowers which may affect aphid consumption in hoverfly larvae. [ABSTRACT FROM AUTHOR]

Agricultural intensification has been implicated in global biodiversity declines. In the European Union, agri‐environmental schemes are designed to address this. For pollinating insects, funding has been provided to sow wildflower mixes. However, previous research indicates that a suite of agricultural weeds are also of great importance to pollinators.Here, we compare the biodiversity associated with the species which are considered harmful to agricultural production and legally deemed as 'injurious' by the United Kingdom 1959 Weeds Act (common ragwort Jacobaea vulgaris, creeping thistle Cirsium arvense, spear thistle C. vulgare, curled dock Rumex crispus and broadleaved dock R. obtusifolius), with plant species recommended for pollinator‐targeted agri‐environmental options.In our field study, the abundance and diversity of pollinators visiting the weed species averaged twice that of the recommended plants and included the main insect orders (Coleoptera, Diptera, Hymenoptera and Lepidoptera). This relationship was also seen in a meta‐analysis of literature data, which indicates that fourfold more flower‐visitor species and fivefold more conservation‐listed species are associated with the weeds. Additionally, the literature shows that twice the number of herbivorous insect species are associated with these plants.We suggest that several factors are responsible for this pattern. Injurious weed species are widely distributed, their flower morphology allows access to a wide variety of pollinator species, and they produce, on average, four times more nectar sugar than the recommended plant species.Freedom of information requests to public bodies such as local councils, Natural England and Highways England indicate that c. £10 million per year is spent controlling injurious weeds. Meanwhile, the cost of the four pollinator‐targeted agri‐environmental options in the United Kingdom exceeds £40 m annually.Synthesis and applications. Our results clearly show that weeds have an underappreciated value to biodiversity. Unfortunately, current UK agricultural policy encourages neither land sparing for nor land sharing with weeds. The UK government is, however, currently committed to overhauling agricultural payments to encourage more wildlife‐ and climate‐friendly practices. Thus, the challenge of reconciling the conflicts between agricultural production and these native and biodiverse species should be a renewed priority to land managers, researchers and policymakers. [ABSTRACT FROM AUTHOR]

Sown wildflower areas are increasingly recommended as an agri-environmental intervention measure, but evidence for their success is limited to particular insect groups or hampered by the challenges of establishing seed mixes and maintaining flower abundance over time. We conducted a replicated experiment to establish wildflower areas to support insect pollinators in apple orchards. Over three years, and across 23 commercial UK orchards with and without sown wildflowers, we conducted 828 transect surveys across various non-crop habitats. We found that the abundance of flower-visiting solitary bees, bumblebees, honeybees, and beetles was increased in sown wildflower areas, compared with existing non-crop habitats in control orchards, from the second year following floral establishment. Abundance of hoverflies and other non-syrphid flies was increased in wildflower areas from the first year. Beyond the effect of wildflower areas, solitary bee abundance was also positively related to levels of floral cover in other local habitats within orchards, but neither local nor wider landscape-scale context affected abundance of other studied insect taxa within study orchards. There was a change in plant community composition on the sown wildflower areas between years, and in patterns of flowering within and between years, showing a succession from unsown weedy species towards a dominance of sown species over time. We discuss how the successful establishment of sown wildflower areas and delivery of benefits for different insect taxa relies on appropriate and reactive management practices as a key component of any such agri-environment scheme. [ABSTRACT FROM AUTHOR]

Governmental agri-environment schemes (AES) aim to improve pollinator abundance and diversity on farmland by sowing wildflower seed mixes. These often contain high proportions of Fabaceae, particularly Trifolium (clovers), which are attractive to some bumblebee species, but not to most of the ~ 240 solitary bee species in the UK. Here we identify wildflowers that are attractive to a greater range of wild bee species. Forty-five wildflower species being farmed for commercial seed production on a single farm were surveyed for native bees. Bee walks were conducted through discrete wildflower areas from April until August in 2018. The results indicate that including a range of Apiaceae, Asteraceae, and Geraniaceae in seed mixes would cater for a wide diversity of bee species. A total of 14 wildflower species across nine families attracted 37 out of the 40 bee species recorded on the farm, and accounted for 99.7% of all visitations. Only two of these 14 species are included in current AES pollinator mixes. Unexpectedly, few visits were made by bumblebees to Trifolium spp. (0.5%), despite their being considered an important food source for bumblebees, while Anthyllis vulneraria and Geranium pratense were highly attractive. For solitary bees, Crepis capillaris, Sinapsis arvensis, Convolvulus arvensis and Chaerophyllum temulum were amongst the best performing species, none of which are usually included in sown flower mixes. We suggest that the standard 'pollinator' mixes used in AES might be updated to include some of these wildflower species, and trialled as seed mixes on farmland. [ABSTRACT FROM AUTHOR]

Using a choice experiment survey this study examines the UK public's willingness to pay to conserve insect pollinators in relation to the levels of two pollination service benefits: maintaining local produce supplies and the aesthetic benefits of diverse wildflower assemblages. Willingness to pay was estimated using a Bayesian mixed logit with two contrasting controls for attribute non-attendance, exclusion and shrinkage. The results suggest that the UK public have an extremely strong preference to avoid a status quo scenario where pollinator populations and pollination services decline. Total willingness to pay was high and did not significantly vary between the two pollination service outputs, producing a conservative total of £379M over a sample of the tax-paying population of the UK, equivalent to £13.4 per UK taxpayer. Using a basic production function approach, the marginal value of pollination services to these attributes is also extrapolated. The study discusses the implications of these findings and directions for related future research into the non-market value of pollination and other ecosystem services. [ABSTRACT FROM AUTHOR]

BACKGROUND: The selective graminicide fluazifop-P-butyl is used for the control of grass weeds in dicotyledonous crops, and commonly applied in amenity areas to reduce grass productivity and promote wildflower establishment. However, evidence suggests that fluazifop-P-butyl might also have phytotoxic effects on some non-target plants. This study investigates the effects of fluazifop-P-butyl on the emergence, phytotoxicity and above-ground biomass of nine perennial wildflower species and two grass species, following pre- and post-emergent applications at half, full and double label rates in a series of glasshouse experiments. RESULTS: While pre- and post-emergent applications of fluazifop-P-butyl caused reductions in seedling emergence and increased phytotoxicity on native wildflower and grass species, these effects were temporary for the majority of wildflower species tested, and generally only occurred at the double application rate. No differences in biomass were observed at any of the rates, suggesting good selectivity and no long-term effects of fluazifop-P-butyl application on the wildflower species from either pre-emergent or post-emergent applications. CONCLUSION: These results have direct relevance to the management of amenity areas for biodiversity, as they confirm the suitability of these wildflower species for inclusion in seed mixtures where fluazifop-P-butyl is to be applied to control grass productivity. Copyright © 2011 Society of Chemical Industry [ABSTRACT FROM AUTHOR]

To protect sweet cherry (Prunus avium L.) against pests in commercial orchards, pesticides are frequently used, but some have adverse environmental impacts. Natural enemies can deliver protection against pests but compared to the surrounding non-crop habitat their abundance is usually low in intensively managed agricultural systems. Wildflower interventions established for Conservation Biological Control as part of Integrated Pest Management (IPM) can reinstate habitat for natural enemies within cropped areas and enhance natural pest control. Over a three-year period, this more sustainable approach to crop protection was investigated in eight sweet cherry orchards protected under polytunnels in the West Midlands (UK). Wildflower strips were established in alleyways between rows of cherry trees and managed under two cutting regimes, Standard Wildflower Strips (SWS) (a single cut in late September) and Actively Managed Wildflower Strips (AMWS) (regularly cut to a height of 20 cm throughout the growing season). These were compared to unsown Control Strips (CS) (original vegetation dominated by grass species). To investigate natural enemy populations and pest regulation services, direct search, Vortis suction sampling, beat sampling, and aphid bait cards were used. Araneae (40.0% of records) and parasitoid wasps (22.7%) were the most frequent natural enemies recorded in alleyways, whilst Anystidae (51.8%) and Araneae (20.8%) were most abundant on cherry trees. Wildflower treatments almost doubled the abundance of natural enemies in alleyways, and increased abundance in cherry trees by ~15% compared to the CS. Wildflower strips increased predation of aphids (bait cards) in cherry trees by 25%. No difference in natural enemy abundance, richness or pest control was recorded between the two wildflower management regimes. Differences in natural enemy abundance and predation rates were detected despite the continued use of pesticides by growers (an average of 5.4 (± 0.4) applications per orchard per year). This study demonstrates that creating wildflower habitat in commercial sweet cherry orchards under polytunnels can boost natural enemies and the associated pest regulation services. Relative to CS, the novel grower-friendly approach of maintaining wildflower strips at a height of 20 cm with regular cutting increased flower resource availability and pest regulation services, demonstrating the potential for growers to adopt this approach as part of a robust IPM strategy. • Wildflower strips can be established successfully under polytunnel systems. • Wildflower strips increased natural enemies and pest regulation services in commercially grown cherry trees. • The novel approach of cutting wildflower strips regularly increased flower numbers and pest regulation services. • Benefits of wildflower provision were recorded despite the continued use of pesticides. [ABSTRACT FROM AUTHOR]

Summary Slugs have been shown to cause severe damage in oilseed rape crops adjacent to sown wildflower strips. Rape can be protected from this damage by broadcasting a recommended dose of metaldehyde over the whole field area. This paper investigates whether severe slug damage can be prevented by applications of metaldehyde just along the wildflower strips thereby reducing the input of chemical molluscicide. In this study, untreated control plots suffered severe crop loss at 1 m from all wildflower strips studied. However, all treatments of molluscicide protected rape from severe crop loss without significant differences among the three treatments (two different concentrations of metaldehyde applied in 50-cm wide barriers along the strips and a recommended dose of metaldehyde broadcast over the whole study area). Arion lusitanicus and Deroceras reticulatum were by far the most abundant slug pests found in the studied rape fields. Arion lusitanicus was very abundant in the wildflower strips and up to 1 m into the field; however, it was almost entirely absent at 3 m from the strips. Since D. reticulatum was evenly distributed over the whole field area, A. lusitanicus appeared to be responsible for the majority of damage in control plots 1 m from the wildflower strips. Application of metaldehyde in a 50-cm wide band has been shown to be practicable and efficient in protecting rape from severe slug damage near to wildflower strips. These reduced applications of molluscicide mean savings of time and money for farmers and can be recommended for practical application. [ABSTRACT FROM AUTHOR]

Horizontal transmission of infectious diseases is strongly determined by the contact network between hosts [1]. Environmental and ecological variables that define the probability of contacts between individuals, such as food resource quality and quantity, have been largely neglected in models studying the dynamics and epidemiology of wildlife diseases. In this work, we used pollinators and their pathogens to study the role of contact networks in a natural multi-host pathogen community. In agricultural landscapes, wild flowers are the most important food resources of insect pollinators such as bees and flies. To boost yields of agricultural crops and ensure pollinator conservation, the UK Environmental Stewardship scheme prompted farmers to grow pollinator-friendly wild flower margins along their fields (Fig. 1). Wild flower margins (Fig. 1) have proven to be efficient to increase both density and diversity of bees in agricultural areas, and to increase pollination success of surrounding crops. As the rate of disease transmission should increase with host density, we hypothesize that the success of wild flower margins may generate hubs for pathogen exchange within the bee community. Several recent studies have illustrated the frequent transmission of infectious diseases between managed and wild bees, potentially via the shared use of flowers [2]. However, the environmental and ecological drivers of disease dynamics between pollinators remain uncharacterised [3]. To understand the role of flower density and diversity for bee disease transmission, we reconstructed high-resolution plant–insect visitor networks from flower visitation data collected in ten farms in Southern England (five farms participating in the scheme vs. five control farms), as well as a record of bee pollen collection to describe the resource bees were exploiting (pollen vs. nectar). When analysing the plant–pollinator networks, we found that flower density and diversity strongly define pollinator density and foraging behaviour, and influence the structure of indirect 'contact networks' among pollinators (via the use of flower species). Particularly, we found flower diversity to be positively correlated with the reduction of niche overlap between insect species. This response of insect pollinators suggest that wild flower margins with high plant species richness may reduce insect competition for resources, and potentially reduce the risk of inter-specific disease transmission by supporting diverse diet for insects exploiting different flowers. To test the effect of plant diversity on pathogen dynamics in bees, we sampled pollinators on these farms and characterized their virome by deep transcriptome sequencing. We are now combining these environmental data to virus discovery in order to reveal the impact of the agri-environmental scheme on viral dynamics. Ultimately, we aim to identify environmental (flower density, agricultural practices) and ecological factors (plant taxa, insect community assemblage) that significantly enhance the transmission of plant and pollinator viral diseases within our model to eventually improve agricultural practises and wildlife management. [ABSTRACT FROM AUTHOR]

• Neonicotinoid residues were found in honey following the European moratorium. • Clothianidin was detected in honey after three years of moratorium. • Thiamethoxam had disappeared from honey after three years. • Foraging on oilseed rape and arable wild flowers increased residue detection. Risks posed to bees from neonicotinoid seed treatments (clothianidin, thiamethoxam, imidacloprid) led in 2013 to the European Union instigating a moratorium for their use on mass-flowering crops, including oilseed rape in the UK. This restriction did allow for the continued use of these seed treatments, in particular clothianidin, on non-flowering crops like winter wheat. To determine the impacts of the moratorium, we assessed neonicotinoid concentrations pre- (2014) and post- (2015−17) moratorium in 347 honey samples collected across Great Britain. While the probability of detecting clothianidin declined immediately following the moratorium, detection rates remained constant over the following three years (mean = 0.10 ppb, maximum = 2.8 ppb). In contrast, after three years thiamethoxam residues entirely disappeared while detection of imidacloprid was infrequent but persistent over the whole period. For those hives where neonicotinoids were detected, there was no evidence that the concentrations in the honey declined over the three years following the ban. Using metabarcoding approaches, we identified plants foraged upon by honeybees during the production of honey. After the moratorium came into effect, the highest neonicotinoid residues were associated with honey produced by foraging on both oilseed rape and several wild plants found in arable field margins. Concerns about soil persistence and uptake by non-target flowering plants ultimately led to a full European Union ban in 2018. Our results suggest that before this full ban came into effect, the use of clothianidin on non-flowering crops maintained a low-level probability of encountering this neonicotinoid within honey. However, these concentrations were low and would have been unlikely to pose significant risks to honeybees. [ABSTRACT FROM AUTHOR]

• Hoverfly diversity was greater in orchards sown with wildflower strips. • Higher levels of pest regulation and earwig abundance in Braeburn orchards. • Wildflower strips did not increase pollination and pest regulation services. • Potential benefits of wildflower strips are masked by PPP regimes. Modern fruit production has successfully increased yields and fruit quality to meet market demands mainly through intensification and the use of Plant Protection Products (PPPs). Due to the associated environmental impacts and consumers increasingly demanding food produced more sustainably, the tree fruit sector is seeking to reduce its reliance on PPPs. Despite intensification, apple production is still highly dependent on ecosystem services, including pest regulation and pollination. The aim of this study was to investigate the response of natural enemies and pollinators in commercial apple orchards to the provision of a wildflower habitat. It was hypothesised that the abundance and diversity of beneficial invertebrate species would be enhanced leading to an increased control of apple pests and enhanced pollination of apple blossom. We also investigated the effect of orchard pesticide toxicity on natural enemies and pest regulation services and how responses varied between apple cultivars (Jazz and Braeburn). The study was carried out in five orchards of each apple variety across Kent (UK), using a split-plot experimental design. At each site, a one-hectare orchard plot was established with wildflower strips in alleyways between rows of trees and compared with a one-hectare control plot where alleyways were managed conventionally with regular cutting. Responses of natural enemies and pollinators were recorded over a period of three and four years, respectively. The presence of wildflower strips did not contribute significantly towards the delivery of natural pest regulation or pollination services. However, hoverfly diversity and species richness were greater in orchards with wildflower strips, and whilst this was not associated with increased rates of pest regulation, such a response could potentially provide more resilient pest regulation and pollination services. Braeburn orchards had higher bee abundance, and pest predation rates, which were associated with a greater abundance of earwigs, compared to Jazz orchards. Of key significance for growers is that high values of cumulative pesticide toxicity negatively affected natural enemy populations, especially earwigs. If growers want to support natural enemies and wild pollinators in modern apple orchards following the principles of ecological intensification, they need to consider both the types and frequency of pesticide sprays used, in conjunction with interventions aimed at promoting beneficial invertebrates. [ABSTRACT FROM AUTHOR]

This article argues the need for, and provides, a dichotomous single access key for the identification of common British wild flower families. A minimum of technical vocabulary is used while at the same time retaining most of the recent botanical names of families. The key provides a user-friendly opportunity for school pupils to become familiar with wild flower families. [ABSTRACT FROM AUTHOR]

The article reports that according to a government survey released in August 2005, seventy-nine percent of 500 unprotected low grasslands in Great Britain are in poor condition. These grasslands had an array of wildlife and wildflowers in the past, but they are missing due to the use of fertilizers, herbicides, and other intensive agricultural methods. On the other hand, some grasslands are undergrazed leading to tall vegetation crowding out lower-growing herbs. Farmers and land managers are encouraged to adopt practices beneficial to the natural environment by the government offering annual payments for 10-year agreements.