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Invasion by invasive alien plants is a global challenge and South Africa has invested billions of Rands to manage invaders through the Working for Water programme. However, regular monitoring after alien plant clearing is hardly done, yet it forms the basis for assessing clearing programme effectiveness, particularly ecosystem recovery trajectories. I monitored both vegetation and soil recovery 6 years after Eucalyptus grandis clearing by Working for Water at Zvakanaka Farm in Limpopo Province of South Africa. Vegetation diversity and soil physical properties were surveyed in 2019 and re‐surveyed in 2022 on fell‐and‐removal and fell‐and‐stackburn cleared treatments and compared to the nearby uninvaded treatment. Results show a significant increase in species richness in 2022 compared to 2019 in the fell‐and‐removal treatment. Cover of both native trees and shrubs as well as forbs was significantly higher in 2022 compared to 2019 in the fell‐and‐removal treatment compared to the fell‐and‐stackburn treatment. Most secondary invaders such as Acacia mearnsii, E. cloeziana, Lantana camara and Rubus rigidus that frequently occurred in 2019 showed decreased occurrence in 2022 on both cleared treatments. Between the two sampling years, soil compaction improved on the fell‐and‐removal treatment only, whereas hydraulic conductivity increased significantly in 2022 compared to 2019 in both the fell‐and‐removal and fell‐and‐stackburn treatments. Soils that were strongly and severely repellent in 2019 in the fell‐and‐stackburn treatment were becoming slightly repellent in 2022. These results show varied vegetation and soil improvements between 2019 and 2022 in both the fell‐and‐removal and fell‐and‐stackburn cleared treatments an indication that recovery is moving towards a positive vegetation and soil recovery trajectory in the direction of the uninvaded treatment. Recommendations for successful passive restoration such as secondary invasion follow‐up clearing are discussed. [ABSTRACT FROM AUTHOR]

Transdisciplinary research has gained traction globally for mapping pathways for sustainable urbanisation. The involvement of local communities is believed to central to knowledge co-production needed to address sustainability challenges. But working with local communities can be challenging. This paper is structured around the authors' personal reflections on undertaking transdisciplinary household energy conservation projects in Ghana and South Africa. The paper reflects on the assumptions and challenges of doing transdisciplinary research in urban Africa and suggests some guidelines for consideration when doing transdisciplinary projects. An inductive analysis of our reflections showed five key challenges: lack of integration, divergent problem identification, tensions in knowledge co-production, asymmetrical power relations, and distrust and managing expectations. We draw on our collective experiences to develop guidelines for conducting transdisciplinary research in urban Africa. These guidelines are not prescriptive but can be useful for a growing and broader audience interested in undertaking transdisciplinary research. [ABSTRACT FROM AUTHOR]

South African terrestrial ecosystems are invaded by hundreds of alien plant species, and large‐scale clearing based on the passive restoration assumption that cleared areas will recover unaided is underway. This study assessed the recovery of vegetation and soil properties, three years following Eucalyptus grandis clearing using fell‐and‐removal and fell‐and‐stackburn methods at Zvakanaka Farm in Limpopo Province, South Africa. The main aim was to ascertain the extent of vegetation and soil recovery, as well as determining which clearing methods facilitate passive vegetation and soil restoration. Results indicate significantly (p < 0.001) lower native species diversity, cover and composition in cleared than in uninvaded sites. However, the recorded low species diversity and composition in cleared sites were more pronounced in the fell‐and‐stackburn than in the fell‐and‐removal sites. Measured soil physical properties varied, with compaction being higher in fell‐and‐removal, whereas soils were more repellent in fell‐and‐stackburn sites. The study concludes that vegetation and soil recovery, following E. grandis clearing, is complex and involves several interacting factors, which are linked to invasion history and intensity. Therefore, for vegetation and soil properties to recover, following E. grandis removal, the clearing programme should consider active restoration techniques, for example soil manipulation and native plant seeding. [ABSTRACT FROM AUTHOR]

Understanding homestead tree holdings is important for developing local conservation and livelihood strategies. However, relative to urban homesteads, tree holdings in rural African homesteads remain little studied, especially in semi‐arid settings. Using ecological and household surveys, this paper examines homestead tree composition, uses and challenges in Checheche, Zimbabwe. In total, 1,594 trees were encountered across 147 homesteads. Nearly, all homesteads (99%) had trees, and most of them were primarily planted for fruits and shade. Fuelwood, traditional medicines, windbreak and homestead decoration were considered as secondary benefits. Overall, tree density was approximately 112 trees/ha, with an average of 11 ± 7.1 trees per homestead. Homestead tree holdings were explained by age and gender of respondent, homestead ownership and importance attached to and knowledge of trees. Challenges to tree planting mentioned include termites, diseases, livestock damage, high temperatures, water shortages and poor quality soils. Overall, this study shows that homestead tree planting is widespread in semi‐arid rural settings but constraints to tree planting ought to be addressed to optimise the benefits from trees. Further research is needed to fully understand the socioecological context that explains tree survival, as a basis for developing interventions for enabling homestead tree planting. [ABSTRACT FROM AUTHOR]

Many studies in South Africa have examined the impacts of alien plants on ecosystems, but none have assessed the impact of guava (Psidium guajava L.) invasion on soil properties. In this study, soils underneath guava‐invaded sites were assessed to determine if they had different soil physico‐chemical properties (pH, P, C, N, Na, K, Ca, Mg, moisture, penetration resistance, infiltration and water repellency) as compared to soils underneath uninvaded sites. Comparisons were made from three different sites over three autumn months. Results show that soil pH was significantly (p < 0.005) higher underneath uninvaded than guava‐invaded sites. Soil P was three times higher underneath guava‐invaded as compared to invaded sites. The soils collected underneath guava‐invaded sites had a significantly (p < 0.001) higher moisture content and were less compact but more repellent than soils from the uninvaded sites. Infiltration rate was significantly (p < 0.001) higher in the uninvaded than the guava‐invaded sites. The study concludes that guava invasion alters some soil properties, thus creating favourable conditions for its growth and making it potentially more invasive. From a management standpoint, guava removal is encouraged; however, given guava's socio‐economic importance more research on cost and benefits is required. [ABSTRACT FROM AUTHOR]

Eucalyptus camaldulensis can be seen as an iconic tree of superlatives. It is the eucalypt with the widest native range, and one of the most widely planted eucalypts around the globe. In South Africa, it is the most widespread and the most aggressively invasive eucalypt. It has many uses, but also causes major impacts. However, little is known about key aspects of its ecology in South Africa, including its invasion history, invasion processes and dynamics, and people's perceptions of its positive and negative effects on ecosystems. Such knowledge is crucial for developing robust and defendable guidelines for sustainable management of the species. This paper provides a comprehensive dossier of the species in South Africa. It reviews what is known of its introduction and planting history, its current distribution, its value for commercial forestry and other uses, its impacts as an invasive species, pests and pathogens associated with the species, people's perceptions of the species and conflicts of interest, and the options for management and restoration. The review reveals that E. camaldulensis is a tree of many contradictions in South Africa, making it a poster-child example of a conflict-generating non-native species. Based on available knowledge, we assess options for improved management. We highlight several knowledge gaps which need to be addressed in more detail through future research. It is hoped that this species profile will serve as a model for the types of information that are needed for developing objective management strategies for non-native tree species in different parts of the world. [ABSTRACT FROM AUTHOR]