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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]

Nurse plants offer microclimates that are favourable to plant growth of understory native vegetation, thus facilitating ecological restoration in degraded old fields. This study examined the impact of three nurse plants on vegetation diversity and soil physical properties in old fields located at Lapalala Wilderness, South Africa. Vegetation surveys in plots measuring 5 m x 5 m under and outside the canopy of nurse plants in both old field and natural sites were conducted. Top soils under and outside the nurse plants canopy were collected in all plots and quantified for soil moisture, soil penetration resistance and soil water repellency. Results indicate that species diversity was high under plant canopy compared to outside plant canopy for all nurse plants. Soils under nurse plants canopy showed improved soil moisture and soil penetration resistance compared to soils outside plant canopy, but no differences were reported for soil water repellency. The study concludes that the presence of native plants under nurse plants canopy points to a positive vegetation recovery trajectory. For vegetation and soil restoration to be effective in Lapalala Wilderness old fields, nurse plants should be protected and active restoration, e.g. seeding or seedling sowing under nurse plants canopy should be considered. [ABSTRACT FROM AUTHOR]

The impact of alien tree clearing on soil and vegetation recovery remains largely understudied. This study focused on changes in soil and vegetation properties following Acacia removal. The aim was to quantify the long-term consequences of alien clearing. Paired cleared (old - 15 years; medium - 11 years; recent - 6 years) and uncleared sites were selected along the Palmiet catchment in Eastern Cape Province, South Africa. Various soil physico-chemical properties (soil moisture, pH, P, N, C, K, Na, Ca, Mg and soil repellency) and vegetation diversity measures were studied on 10 m × 10 m plots. Results indicate that measured soil nutrients are significantly ( P < 0.05) lower in cleared than in uncleared sites. However, comparisons among cleared sites alone indicate that soil properties are recovering with older cleared sites having higher ( P < 0.05) nutrients than recent cleared sites. Soils in uncleared sites are more repellent than soil in cleared sites. Vegetation recovery in cleared sites was taking place with older cleared sites having higher native species diversity than recently cleared site. We conclude that the removal of alien plants could have caused a reduction in soil nutrients. However, as native vegetation recovers on cleared sites, soil nutrients are gradually improving. [ABSTRACT FROM AUTHOR]

Lantana camara L. is an invasive alien shrub of worldwide significance due to its impacts on biodiversity. It can alter the soil properties of invaded ecosystems and, as a result, affect management outcomes. However, knowledge on the impacts of L. camara on soil properties is scanty, especially in South Africa, despite the pervasive presence of the plant in the country. In this comparative study, the soils underneath L. camara were assessed in order to determine if they had different properties (soil physico-chemical properties, penetration resistance, infiltration, hydraulic conductivity and water repellency) in comparison to the soils in adjacent natural sites in the Eastern Cape, South Africa. Soil samples were collected from the top soil beneath the canopy of both L. camara-invaded and adjacent natural sites in five different locations over three summer months. The soils that were collected from underneath L. camara had a significantly higher total C, total P, gravimetric soil moisture (in November and December) and were repellent, compared to the soils in the adjacent natural sites. Soil penetration resistance was significantly higher in the natural sites than in the L. camara-invaded sites. The soil hydraulic conductivity, soil infiltration rate, soil pH, exchangeable cations and total N showed no significant difference between the invaded and the natural sites. It appears that the soils underneath L. camara have a high total C and total P, soil moisture and are repellent, thus influencing nutrient cycling, potentially making the soil properties underneath it ideal for its own growth. This could contribute to the success of L. camara as an invasive species. [ABSTRACT FROM AUTHOR]

The article presents a report on ecological restoration of the Renosterveld shrubland South Africa which consists of endangered vegetation type of South Africa's Cape Floristic Region. It mentions presence of fire prone shrubland which is dominated by shrubs of the Asteraceae family such as Elytropappus rhinocerotis. It also states the diversity of geophytes and lawn grasses in the area.