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Agroforestry systems, where productive trees are integrated into agricultural land, can deliver benefits to biodiversity, natural pest control, and pollination, but the effects are highly variable. Recent advances in our understanding of flower strips in agricultural systems suggest that the management of the tree row understorey could be an important contributor to this variation. Here, we compare two cutting regimes for an understorey, originally seeded with the same flower mix, in the tree rows of an apple-arable agroforestry system: (i) uncut vegetation to promote a flowering understorey, and (ii) regularly mown vegetation. We recorded the effects of management on invertebrate pests, natural enemies, and pollinators, in both the apple and arable components. Apple trees above flowering understoreys supported significantly: (i) more natural enemies early in the season, (ii) fewer aphid colonies, (iii) fewer aphid-damaged fruits, and (iv) higher pollinator visitation, compared with those above mown understoreys. In the arable crop alleys, both the taxonomic richness and Shannon diversity of ground-based natural enemies were significantly higher adjacent to flowering understoreys, compared with those adjacent to mown understoreys, early in the season. Financial modelling based on aphid damage to apples, mowing costs, and income from Countryside Stewardship grants, indicated that flowering understoreys increased farm income by GBP 231.02 per ha of agroforestry compared with mown understoreys. Our results provide the first empirical evidence that management to promote flowering understoreys in agroforestry systems can be a win-win option to improve invertebrate diversity, associated ecosystem services, and farm income.

Organic food systems are recognised as an important component in meeting United Nations’ (UN) Sustainable Development Goals. A leverage points perspective can help to identify approaches which have the potential to facilitate transformative systemic change towards organic and sustainable farming. Using fuzzy cognitive maps developed from expert stakeholder opinions, we modelled a system of drivers of organic food production and consumption in the United Kingdom, according to the UN Sustainability Assessment of Food and Agriculture systems framework. The most influential concepts in the uptake of organic systems were related to system norms and values and social structures, such as short-term economic thinking, landowner engagement, and relationships with certification bodies. However, in a scenario analysis, organic stakeholders identified relatively shallower leverage points as more likely to change under a sustainable future, resulting in limited systemic change. This demonstrates the need for policies targeting system norms, values and social structures relating to food systems to facilitate the transition to organic and sustainable farming.

Climate change and the withdrawal of several classes of agrochemicals from use are intensifying the challenges faced by food producers in controlling pests in crop systems. Integrated pest management (IPM), which uses a combination of pest control approaches, is therefore a focus in international initiatives to improve the resilience of food production. Integrating the greater use of trees and shrubs on farms within IPM frameworks offers a biodiversity‐positive contribution to crop protection. For example, trees can modulate the prevalence and impacts of agricultural pests and their natural antagonists through direct and indirect interactions. The beneficial impact of farmland trees and shrubs on pest management in arable or grassland fields can be enhanced from an analysis of variables such as tree species and their spatial distribution on farms, insect‐plant dynamics, population behaviours and soil management practices. The aim of this study is to synthesise existing knowledge and to assess the benefits and trade‐offs between farmland trees and IPM strategies, building on gaps in knowledge identified by a stakeholder survey. Through this targeted review, we delineate the future evidence required to define and quantify the advantages that farmland trees offer as an element of IPM strategies. Practical implication. The development of regional biodiversity monitoring tools, which integrate landscape features such as trees, shows promise for shaping national policies to increase the adoption of IPM. There is a demand for user‐friendly on‐farm tools, adaptable to changing crop and pest priorities, that can support the alignment of the management of farm trees with IPM. However, basic and applied biological and ecological research are needed to inform and validate these decision‐support tools and the capability to inform landscape‐scale models. Conceptual figure representing the three topics assessed in this review. Components include the crops, invertebrates, and trees and their arrangements. Interactions refer to the dynamic relationships between these components and management interventions. Opportunities include the measuring, promotion, better use of resources, research and demonstration and initiatives.

Effective early detection, monitoring and management methods are critical for reducing the impacts of insect pests in agriculture and forestry. Combining host plant volatiles with sex pheromones could enhance trapping methodologies, whilst the use of non-host volatiles could improve the effectiveness of pest management through repellency effects. In this meta-analysis approach, we analysed 51 studies that used electroantennograms (EAG), wind tunnels and/or field traps to evaluate the antennal and behavioural responses of Lepidoptera to sex pheromones combined with attractant or repellent plant volatiles. Proposed attractant plant volatiles had a positive association with female Lepidoptera responses to sex pheromone, but effects on males were highly variable, with unexpected repellency reported in some studies. Proposed repellent plant volatiles were significantly or near-significantly negatively associated with male attraction to sex pheromones but were scarcely studied. Sub-group analysis identified that male responses to sex pheromone were reduced when the dose of attractant plant volatile relative to sex pheromone was increased. Green-leaf volatiles were associated with the strongest positive effects for males in field traps. Multiple-compound attractant plant volatile blends were less effective than single compounds in field studies. Our analysis demonstrates, (i) the potential value of combining host plant volatiles with sex pheromones to capture females rather than only males, (ii) the importance of identifying appropriate host plant volatiles and optimal relative doses, and (iii) the potential for non-host plant volatile use in pest management strategies.

Diversified farming systems, for example those that incorporate agroforestry elements, have been proposed as a solution that could maintain and improve multiple ecosystem services. However, habitat diversification in and around arable fields has complex and inconsistent effects on invertebrate crop pests and their natural enemies. This hinders the development of policy recommendations to promote the adoption of such management strategies for the provision of natural pest control services. Here, for the first time, we conducted a trait-based approach to investigate the effect of farming system on plant, invertebrate herbivore, and invertebrate natural enemy communities. We then evaluated this approach by comparing the results to those generated using a traditional taxonomic approach. At each of three working farms, we sampled within an agroforestry field (a diverse farming system comprising alleys of arable crops separated by tree rows), and within a paired non-diversified area of the farm (arable control field). Each of 96 sample points was sampled between 8 and 10 times, yielding 393,318 invertebrate specimens from 344 taxonomic groups. Diet specialization or granivory, lack of a pupal stage, and wing traits in invertebrates, along with late flowering, short flowering duration, creeping habit, and perenniality in plants, were traits more strongly associated with agroforestry crop alleys than the arable control fields. We hypothesize that this is a result of reduced habitat disturbance and increased habitat complexity in the agroforestry system. Taxonomic richness and diversity were higher in the agroforestry crop alleys compared to the arable control fields, but these effects were stronger at lower trophic levels. However, functional trait diversity of natural enemies was significantly higher in the agroforestry crop alleys than the arable control fields, suggesting an improved level of biocontrol, which was not detected by traditional diversity metrics. Of eight key pest taxa, three were significantly suppressed in the agroforestry system, while two were more abundant, compared to the arable control fields. Trait-based approaches can provide a better mechanistic understanding of farming system effects on pests and their natural enemies, therefore we recommend their application and testing in future studies of diversified farming systems.

In-field trees are thought to buffer arable crops from climate extremes through the creation of microclimates that may reduce the impacts of heat, wind, and cold. Much less is known about how trees and their biotic interactions (e.g. with natural enemies of pests and wild understory plants) impact crop yield stability to biotic stresses such as crop pests and disease. Modelling these interactions using conventional approaches is complex and time consuming, and we take a simplified approach, representing the agroecosystem as a Boolean regulatory network and parameterising Boolean functions using expert opinion. This allies our approach with decision analysis, which is increasingly finding applications in agriculture. Despite the naivety of our model, we demonstrate that it outputs complex and realistic agroecosystem dynamics. It predicts that, in English silvoarable, the biotic interactions of in-field trees boost arable crop yield overall, but they do not increase yield stability to biotic stress. Sensitivity analysis shows that arable crop yield is very sensitive to disease and weeds. We suggest that the focus of studies and debate on ecosystem service provision by English agroforestry needs to shift from natural enemies and pests to these ecosystem components. We discuss how our model can be improved through validation and parameterisation using real field data. Finally, we discuss how our approach can be used to rapidly model systems (agricultural or otherwise) than can be represented as dynamic interaction networks.

Meta-analyses have become a valuable tool with which to synthesize effects across studies, but in ecology and evolution, they are often characterized by high heterogeneity, where effect sizes vary between studies. Much of this heterogeneity can be attributed to species-specific differences in responses to predictor variables. Here, we aimed to incorporate a novel trait-based approach to explain species-specific differences in a meta-analysis by testing the ability of morphological traits to explain why the effectiveness of flight-intercept trap design varies according to beetle species, a critical issue in forest pest management. An existing morphological trait database for forest beetles was supplemented, providing trait data for 97 species, while data from a previous meta-analysis on capture rates of bark or woodboring beetles according to different trap designs were updated. We combined these sources by including nine morphological traits as moderators in meta-analysis models, for five different components of trap design. Traits were selected based on theoretical hypotheses relating to beetle movement, maneuverability, and sensory perception. We compared the performance of morphological traits as moderators versus guild, taxonomic family, and null meta-analysis models. Morphological traits for the effect of trap type (panel vs. multiple-funnel) on beetle capture rates improved model fit (AICc), reduced within-study variance (σ²), and explained more variation (McFadden’s pseudo-R²) compared with null, guild, and taxonomic family models. For example, morphological trait models explained 10% more of the variance (pseudo-R²) when compared with a null model. However, using traits was less informative to explain how detailed elements of trap design such as surface treatment and color influence capture rates. The reduction of within-study variance when accounting for morphological traits demonstrates their potential value for explaining species-specific differences. Morphological traits associated with flight efficiency, maneuverability, and eye size were particularly informative for explaining the effectiveness of trap type. This could lead to improved predictability of optimal trap design according to species. Therefore, morphologicaltraits could be a valuable tool for understanding species-specific differences in community ecology, but other causes of heterogeneity across studies, such as forest type and structure, require further investigation.

Compared to monocultures, agroforestry can promote biodiversity, ecosystem functioning and climate resilience, whilst maintaining or enhancing production and profits. Despite this, uptake in temperate regions remains low. Knowledge gaps amongst land managers are a primary barrier to uptake, but little is known about which aspects of agroforestry management are hindering uptake specifically, or how to address them. We use a mixed‐method approach to identify knowledge barriers to agroforestry adoption in the UK and co‐design solutions to them. To identify barriers, we interviewed 27 farmers in 2023–2024. We used a perception matrix to quantitatively assess their perceptions of 12 agroforestry knowledge elements (e.g. tree species, inputs, markets) against eight perceptions (e.g. information is important, available or trustworthy). To identify solutions, we used the interview results to direct focus group discussions at a multi‐actor workshop with 48 participants, including farmers, policymakers, NGOs and other stakeholders. We then conducted a framework analysis to identify shared solutions and create an evidence‐based educational agenda. We found that the perceived knowledge gaps were greater for the business elements (e.g. financial or legal impacts) than the ecological elements (e.g. understory management) and that the relative importance of the learning barriers differed between elements. Averaging across elements, the largest barriers were time constraints and a shortage of trusted information. The proposed solutions to the knowledge gaps included (for example) designs for open‐access online tools for independent learning, innovative mechanisms to fund farmer‐to‐farmer mentoring, agroforestry accreditation to enhance trust in advice and policy reforms to education. Creating living labs or demonstration farms could provide multiple benefits in parallel. We consolidated the solutions into a 10‐step educational agenda. This evidence‐based agenda for agroforestry education reflects the views of UK stakeholders across the agricultural supply chain. It is directly relevant to policymakers, agricultural advisors and educators, and researchers and their funders. Many of the solutions are straightforward to implement and could promote agroforestry uptake quickly, whereas others are systemic and require multi‐organisational collaboration. Equipping farmers with the knowledge needed to adopt agroforestry and manage it effectively will help us to build a more climate‐resilient and sustainable future. Read the free Plain Language Summary for this article on the Journal blog. Read the free Plain Language Summary for this article on the Journal blog.

1. Climate change and the withdrawal of several classes of agrochemicals from use are intensifying the challenges faced by food producers in controlling pests in crop systems. Integrated pest management (IPM), which uses a combination of pest control approaches, is therefore a focus in international initiatives to improve the resilience of food production. 2. Integrating the greater use of trees and shrubs on farms within IPM frameworks offers a biodiversity-positive contribution to crop protection. For example, trees can modulate the prevalence and impacts of agricultural pests and their natural antagonists through direct and indirect interactions. The beneficial impact of farmland trees and shrubs on pest management in arable or grassland fields can be enhanced from an analysis of variables such as tree species and their spatial distribution on farms, insect-plant dynamics, population behaviours and soil management practices. 3. The aim of this study is to synthesise existing knowledge and to assess the benefits and trade-offs between farmland trees and IPM strategies, building on gaps in knowledge identified by a stakeholder survey. Through this targeted review, we delineate the future evidence required to define and quantify the advantages that farmland trees offer as an element of IPM strategies. 4. Practical implication. The development of regional biodiversity monitoring tools, which integrate landscape features such as trees, shows promise for shaping national policies to increase the adoption of IPM. There is a demand for userfriendly on-farm tools, adaptable to changing crop and pest priorities, that can support the alignment of the management of farm trees with IPM. However, basic and applied biological and ecological research are needed to inform and validate these decision-support tools and the capability to inform landscape-scale models