Research

INTRODUCTION

Current sustainability challenges facing society call for more innovative ways of learning and managing the interconnectedness of social-ecological systems (Bennett et al. 2015, Díaz et al. 2015, Mooney 2016, Turner et al. 2016, Partelow et al. 2019). Given the links between socioeconomic and ecological systems, addressing current challenges requires accounting for social-ecological dynamics and supporting adaptive decision-making processes (Ostrom 2009, Reyers et al. 2015, 2018, Partelow et al. 2019). An ideal approach is to involve local land users in ecosystem monitoring, management, and rehabilitation. This involvement may improve the understanding of ecosystem functioning and possibly avoid crossing critical thresholds (Olsson et al. 2004, Miller and Morisette 2014, Bennett et al. 2016, Gavin et al. 2018, Selomane et al. 2019).

Until recently, invasion biology has focused on how invasive alien species invade and adapt to new environments (Schultz and Dibble 2012, Grigulis et al. 2013, Te Beest et al. 2015, Ahmad et al. 2019). In contrast, work on understanding human adaptation to invasive species has been limited (Aitken et al. 2009, Urgenson et al. 2013, Vaz et al. 2017a, Shackleton et al. 2019a). Despite a growing understanding of social factors affecting invasive species management (Dickie et al. 2014, Shackleton et al. 2016, 2019b, Zengeya et al. 2017, Novoa et al. 2018), understanding of social factors behind land users’ motivations to participate in invasive species control remains limited (Urgenson et al. 2013, Shackleton et al. 2016, Vaz et al. 2017a, Potgieter et al. 2019, Yletyinen et al. 2021). Managers of restoration programs increasingly realize that the success of ecosystem restoration is strongly affected by decisions taken by land users within the system, and their willingness to participate in the management programs (Urgenson et al. 2013). However, a significant challenge has been the lack of understanding of the factors affecting land users’ participation, and lack of knowledge of the land users’ motives for involvement in restoration programs and activities (Biggs et al. 2015, Novoa et al. 2018).

Land users’ motives to participate in conservation and restoration activities are informed by the context and by their perceptions of the key ecosystem services gained (Oteros-Rozas et al. 2015, Selinske et al. 2015, Jacobs et al. 2016, Crowley et al. 2017, Guerrero et al. 2018). Therefore, understanding land users’ views within different contexts is essential for identifying and comprehending the opportunities and constraints for ecosystem restoration (Gavin et al. 2018, Luvuno et al. 2022). For instance, if landowners do not perceive a particular invasive species as problematic, and thus controlling it as valuable for benefits such as livestock grazing or biodiversity restoration, there is little motivation to participate in its control (Zengeya et al. 2017, Novoa et al. 2018, Potgieter et al. 2019). Therefore, research needs to also focus on land users’ values to formulate an approach that is cognizant of their beliefs and values (Hernández-Morcillo et al. 2013, Rist et al. 2016, Masterson et al. 2017, Wartmann and Purves 2018). Another critical social aspect to consider includes land user diversity, i.e., differences in land users’ characteristics, motivations, goals, attitudes, and abilities, all of which may influence their invasive species management interests and capacities. High land user diversity generally benefits invasive species management when common goals and aspirations amongst land users are shared (Shackleton et al. 2015, 2019c, Novoa et al. 2018, Bennett and van Sittert 2019, Potgieter et al. 2019). On the other hand, it can complicate conservation efforts if land users differ in their opinions on the need to control invasive species when resources are limited, or struggle to establish common management rules for the control of invasive species (Aretano et al. 2013, Wartmann and Purves 2018, De Vreese et al. 2019, Cumming et al. 2020).

Efforts to control invasive alien plants (IAPs) in South African ecosystems have been championed through a national-scale program called Working for Water (WfW). Working for Water was established to control the spread of IAPs to conserve natural resources while contributing to poverty alleviation by providing jobs to rural people (van Wilgen et al. 2012). The program’s progress in reducing environmental impacts from IAPs has been hindered in many parts by a lack of monitoring of cleared areas. Limited restoration initiatives, and a lack of attention on the reduction of seedbanks as part of the WfW program’s overall control strategy, have contributed to the limited success of the program (van Wilgen et al. 2012, Ntshotsho et al. 2015, van Wilgen and Wannenburgh 2016). This has resulted in many areas that were cleared being susceptible to reinvasion by the same or different invasive species (De Neergaard et al. 2005, van Wilgen et al. 2012).

Australian wattles (mainly, Acacia dealbata, A. mearnsii, and A. decurrens), fast growing leguminous trees (4–9 m tall) of the Fabaceae family, native to Australia, have invaded large areas of grasslands in the upper Umzimvubu catchment in South Africa. Their spread is linked to anthropogenic influences such as grazing practices, abandonment of croplands, and settlement patterns (Gwate et al. 2016, Gouws and Shackleton 2019a, Shackleton et al. 2019d). Additionally, wattles in the upper Umzimvubu catchment have been perceived as an important livelihood source by some local land users because they provide ecosystem services such as firewood, shelter for livestock, and other timber products (Kull et al. 2011, Ngorima and Shackleton 2019, Yapi et al. 2023). On the other hand, negative perceptions of some agencies and land users toward wattles in the area persist as they increase in abundance and continue to spread across the landscape, with growing evidence of negative impacts on biodiversity, ecosystem services, and livelihoods (De Neergaard et al. 2005, Yapi et al. 2023). As such, there is a growing need to design management interventions that are consistent with land users’ desires and needs (Shackleton et al. 2019e). The Umzimvubu catchment presents an ideal opportunity to conduct such case studies because of its diverse social-ecological systems occurring alongside one another, including communal and commercial farming land tenure systems, thus providing important insights into the opportunities and challenges faced by different socioeconomic landscapes.

In South Africa, communal land tenure systems are dominated by extensive livestock farming (at or above nominal carrying capacities) by mostly relatively high densities of low-income households, with many depending on government grants for cash income. Land management is vested in traditional/customary authorities headed by chiefs and village headmen. The legacy of the apartheid regime remains strongly reflected in terms of the lack of government support and essential services delivery (Nnadozie 2011). On the other hand, commercial farming systems are generally located on freehold, private tenure lands with low population densities and reasonably secure incomes. Land management practices are more concerned with maximizing economic returns from livestock production resulting in grazer-dominated systems with moderate but constant stocking rates. In general, commercial farms involve more active land management compared to communal land tenure systems. Because of their higher financial incomes and resources, commercial farming systems are less reliant on local ecosystems for ES, as they can secure their basic needs for essential ES through market supplies from more distant ecosystems. Within this context, we sought to investigate (i) land users’ perceptions of wattle clearing activities on both communal land tenure and commercial livestock farming systems; and (ii) to explore opportunities and challenges to wattle management as perceived by two of the land user groups in the upper Umzimvubu catchment.

MATERIALS AND METHODS

Study area

This study was conducted in the Umzimvubu catchment, in the northern region of the Eastern Cape province and on the eastern border of the KwaZulu-Natal province of South Africa. From the foot of the Drakensberg Mountains, at the Lesotho border, the catchment drains southeast into the Indian Ocean. The climate in the area ranges from temperate, with high frost frequency in the northern, higher altitudes, to sub-tropical along the coastal belt. It is a summer rainfall area, with annual average rainfall ranging from approximately 650 to 1000 mm in the higher-lying areas of the upper catchment and along the coastal areas, respectively (Mucina et al. 2006). The vegetation is mostly grassland, occupying approximately 69% of the catchment, along with savanna (21%), coastal forest (8%), and thicket (2%) biomes covering the remainder. Grasslands cover the northern and central areas of the catchment, while savanna is represented in the central and western areas (Mucina et al. 2006).

The study area was selected on the basis of being in the current range of wattle invasion in the upper section of the Umzimvubu catchment, including Matatiele (30.53°S; 28.57°E, Cedarville (30.49°S; 28.57°E), Kokstad (30.07°S; 29.69°E), and Mount Frere (30.70°S; 28.8°E). The area includes sites with juxtaposed private and communal land tenure systems. Matatiele, Mount Frere, and Kokstad are the three main towns in the study area with populations of 12,466, 5252, and 51,561, respectively. Cedarville is a small town (with approximately 5000 people) serving private and commercial livestock farms. The different land use systems represent the area’s prevailing environmental and socioeconomic conditions.

The total population of the Umzimvubu catchment is approximately 2.2 million people, with 85% residing in rural communal tenure villages and dependent, to varying extents, on directly accessible natural resources such as fuelwood, medicinal plants, and fencing poles for livelihoods (UCPP 2011). Many people in the area depend on government social grants as their primary source of cash income. The main livelihood activities in the area include extensive livestock grazing in rangelands and crop farming, which is coupled, in some parts, with state food projects. Most rural households in communal areas report cash incomes of just over R600 (approx. US$38) per month (UCPP 2011). Commercial farming in the area is mainly dominated by beef production, along with some dairy and livestock fodder production (UCPP 2011). Most commercial farmers depend on wages through formal employment and income from the farm business (Yapi et al. 2023). Clearing of wattles by the WfW program, on communal land, started in the area between 2013 and 2014 in partnership with locally based organizations that form part of a multi-stakeholder platform known as Umzimvubu Catchment Partnership Programme (UCPP).

Data collection

Two groups of farmers were identified, namely communal land users and commercial livestock farmers on private tenure farms. Communal households were randomly selected across three villages: Colana (near Mount Frere), Mvenyana, and KwaMzongwana (near Matatiele). The villages were selected in collaboration with the local NGO, Environment and Rural Solutions (ERS), based on the density of wattle invasion, and current and historical wattle clearing activities. Commercial private farms were sampled in the vicinity of Matatiele, Kokstad, and Cedarville. A list of commercial farmers was obtained from the ERS. This was followed by a snowball approach (Biernacki and Waldorf 1981), where participants were asked to suggest names of other commercial livestock farmers with wattles or a history of wattle invasion on their farms. With most respondents speaking fluent isiXhosa, Sesotho, and English, interviews were conducted in isiXhosa or English, depending on the interviewees’ preference. In the case of only four respondents from communal areas who preferred Sesotho, the services of a Sesotho translator were used because the lead researcher was fluent only in isiXhosa and English. In each household, the oldest available and willing member of the family was interviewed. A total of 100 interviews was sought; however, because of the small number of commercial farmers that met the selection criteria of having wattles on their lands, this number could not be achieved. Consequently, 77 interviews were conducted across different sites, including 65 communal land users and 12 commercial farmers. Interviews were based on a semi-structured questionnaire comprising a mix of open-ended, closed-ended, and ranking questions (Sloane-Seale 2009). Drawing from the results of the study conducted in the same study area, which investigated land users’ perceptions of wattle invasion (Yapi et al. 2023), our starting assumption was that respondents regarded wattle invasion in the landscape as a problem and wanted it to be managed.

The interviews were designed to understand land users’ perceptions of how wattle clearing has impacted their livelihoods (interim of benefits and costs) and the environment. The interviews were also used to gain insights into the land users’ perceptions of the opportunities and challenges to wattle management in the landscape. The open-ended questions allowed respondents’ perceptions of the benefits and costs of wattle clearing to emerge without pre-empting, while the closed-ended questions allowed for quantitative analysis of the key constructs. Respondents were asked (i) if there were wattle management interventions currently being implemented in the landscape (including the length of time such interventions have been in place); (ii) their perceptions of the current wattle clearing practices (whether the clearing practices were successful or not). (iii) whether wattle clearing operations had any impacts on their livelihoods (including perceived benefits); (iv) whether the wattle clearing had effects on household income (and how); (v) their perceptions of the motives and barriers for participating in wattle management; (vi) their perceptions of the potential incentives and motives for land user participation in wattle management; (vii) about the type of livestock they keep (including reasons for keeping livestock); and (viii) the socio-demographic information of the household (including ownership of household assets such as cars, tv, and fridge). The socio-demographic information of the household, including household assets and livestock ownership, were used to calculate a wealth index score. Surveys in communal areas took place between 08h30 and 17h30 during weekdays. We avoided interviews in communal households on weekends as such are often reserved for important cultural or religious activities. Interview appointments with commercial farmers were pre-arranged via phone call and therefore were not limited to weekdays. Interviews took approximately 40 minutes per respondent.

Ethics approval for the study was via the Screening Committee of the Department of Environmental Science, Rhodes University (Reference Number ES17/26). Participation was voluntary; participants were informed about their right to refuse to answer any questions and to withdraw from the interview at any time should they wish to do so. Informed consent was obtained from the participants and anonymity and confidentiality were explicitly granted. Questionnaires did not include any personal information that could be used to identify individuals, and thus, all data was anonymized prior to analysis.

Analysis

Questionnaire responses were grouped into categories, describing land users’ perceptions of wattle clearing practices, benefits, and costs associated with wattle clearing as well as their perception of barriers and enablers for wattle clearing. We used thematic coding and a grounded theory approach to identify emergent themes in land users’ responses to open-ended questions (Corbin and Strauss 1990). Subsequently, statements were coded as 0 or 1, corresponding to the absence or presence, respectively, of a theme in an interview script. This enabled us to examine associations between themes and land user groups and participant’s responses to closed-ended questions. A wealth index was constructed as the sum of the number of wage earners, social grants, total assets such as cars, television, refrigerator, and livestock (all standardized between 0 and 1 against the highest value) per household. Livestock categories were converted into large stock units (LSU), using specific coefficients for each livestock category, which is an equivalent of one head of cattle with a body of weight of 450 kg and gaining 500 g per day (Meissner et al. 1983, Mokolobate et al. 2017). Subsequently, the wealth index was ranked into quartiles, (poorest, poor, wealthy, and wealthiest).

Multivariate analysis (Principal Component Analysis [PCA] and Cluster Analysis) were run to examine associations between the respondents’ socio-demographic variables and their responses to closed-ended questions. Chi-square tests were used to determine differences between land user groups on perceptions on wattle clearing practices, barriers and enablers associated with wattle clearing. All analyses were performed using STATISTICA ver. 14 software (TIBCO Software Inc. 2019).

RESULTS

Demographic profile of the two land user groups

Most respondents from both commercial and communal households were males, with an average age of just over 50 years (Table 1). Commercial households generally have higher levels of education than communal ones, as reflected by the average number of people with tertiary education. Many communal households in the area depend on government grants for cash income, whereas commercial farmers rely on wages and income from the farm business.

Land users’ perceptions of the current clearing practices

The PCA results revealed strong negative associations between the demographic variables of wealth and education and land users’ perception of wattle clearing benefits. High education and wealth status correlated with low perception of benefits (Fig. 1).

When asked about the current wattle management interventions in the landscapes, a majority of communal land users affirmed that wattle clearing in the areas has been ongoing since 2013/2014. And similarly, all the commercial farmers had ongoing activities to control wattle invasion on their farms (Table 2). Land users were asked about their perceptions of the current clearing operations, whether they viewed the current clearing operations as successful in controlling wattle. Significantly (p = 0.04), most communal respondents (73%) perceived interventions by WfW to be successful, whereas 42% of commercial farmers perceived their interventions to be successful (Table 2). When asked how the removal of wattle from the landscape had impacted their livelihoods as well as household income, two-thirds (68%) of communal land users and a half (50%) of commercial farmers perceived clearing of wattle as having positive impacts on their livelihoods (Table 2). Communal land users mentioned job opportunities that opened up through the Working for Water program as one of the positive impacts associated with wattle clearing. On the other hand, commercial farmers mentioned that removing wattle from the grazing areas resulted in better grazing conditions for their livestock.

Furthermore, significantly (p = 0.03) more commercial farmers (67%) mentioned that removal of wattle had positive benefits on farm income as compared with only 32% of communal land users (household income; Table 2). On the other hand, when asked if and how wattle clearing has harmed their livelihoods, one-sixth (15%) of communal land users were unhappy with the wattle clearing operations, stating that they believed that it facilitated the spread of wattles instead of their control (Table 2).

Land users’ perceptions of wattle clearing benefits

Respondents mentioned several direct and indirect benefits that were obtained once wattle had been removed from the landscape (Table 3). Significantly (p = 0.02) more commercial farmers (75%) reported improved grazing capacity as a benefit compared to 39% of communal land users. The most commonly cited clearing benefit for both commercial and communal farmers was improved water flow (75% and 71%, respectively) from the streams and rivers (Table 3).

A proportion of respondents from both communal areas (38%) and commercial farmers (58%) noted that it became easier to access different parts of the landscape once wattle was cleared. A significantly greater proportion (p = 0.04) of commercial farmers (50%) mentioned easy access to livestock as a clearing benefit compared to 22% of communal land users (Table 3). A small proportion of respondents mentioned the availability of fuelwood from felled trees as one of the benefits of wattle clearing. Eight percent of commercial farmers and 16% of respondents from communal areas did not recognize any benefits from wattle clearing.

Land users’ perceptions of the motives and barriers to wattle management and stakeholder participation

Respondents suggested six different reasons as motives for removing wattle, but there were no overlaps between the reasons given by the two land user groups (Fig. 2). Only a small portion of communal farmers voluntarily removed wattle from the landscape, yet a majority of communal farmers were involved in wattle removal because of the employment opportunity provided by the WfW program. A third of commercial farmers mentioned that they removed wattle from their farms to improve water supply, and 50% reported doing so to improve grazing capacity. One-quarter (25%) of commercial farmers reported wanting to keep wattle under control (Fig. 2).

On the other hand, six reasons were given by both land user groups as barriers and causes for not controlling the spread of wattle (Fig. 3). Thirty-five percent of commercial farmers mentioned that a significant barrier was the high cost of clearing wattle. The cost was too high and unsustainable because wattle keeps growing back from coppice or seed banks. On average, commercial farmers reported spending between ZAR10 000 (US$506) and ZAR 37 000 (US$1871) per hectare on wattle control. One-fifth of communal land users (20%) mentioned that they could not participate in wattle clearing because they were too old to participate in strenuous physical activities. A minority of respondents in communal areas mentioned a lack of incentives and employment as the reason for not controlling wattle spread in the landscape. The majority of the respondents mentioned that they would rather be looking for more permanent and secure jobs elsewhere instead.

Land users’ perceptions of potential incentives and motives for participation (adaptive measures)

Employment (23%) and fencing of grazing areas (19%) were identified as potential enablers of wattle control by communal farmers (Fig. 4). Respondents believed that fencing of grazing areas (grazing camps) would lead to good grazing practices and make it easy to manage and control wattle in these areas. A small portion of communal farmers (10%) mentioned that they were willing to remove wattle in some parts of the landscape (such as roadsides and homesteads), as long as some financial incentives were available or that they were provided with the necessary tools. On the other hand, a small minority of commercial farmers mentioned that, although they are currently managing wattle invasion in their farms, some form of assistance from the government would go a long way in helping them deal with wattle invasion in their properties. They reported that sometimes they have to hire heavy machinery to remove big wattle trees, and they need to pay their farm employees extra for such work, amongst other additional costs. A few commercial farmers (8%) mentioned that the promise of good grazing and other related benefits after wattle removal is what motivates them to take part in wattle management (Fig. 4).

DISCUSSION

To understand land users’ environmental behaviors, consideration is required of both internal factors and the external context in which land users operate. However, understanding farmers’ environmental behavior is complex. This complexity is underlined by the heterogeneous nature of the farming systems, and therefore the context for decision making in relation to the environment will vary (Yapi et al. 2023). Each social-ecological setting is underlined by particular attitudes, values, and socioeconomic factors of the individuals or communities. These affect individual farmer’s responses to undertaking environmental activities voluntarily (Bennett et al. 2015, Hamann et al. 2015, Reyers et al. 2018).

The study explored farmers’ views on the current wattle clearing practices, motives and disincentives to control wattles in the landscape. Communal stakeholders acknowledged the WfW clearing program’s positive impacts on their livelihoods, especially with respect to providing employment opportunities for some. The positive effects that the WfW program has had on livelihoods generally since its inception have been well documented (McConnachie et al. 2012, Wise et al. 2012, Ntshotsho et al. 2015, van Wilgen et al. 2020, Zengeya and Wilson 2020). One of the main goals upon which the WfW program was founded was to reduce poverty in marginalized communities. In this regard, the program continues to make commendable efforts in empowering poor communities (van Wilgen et al. 2012). On the other hand, commercial farmers were content with their efforts in dealing with invasive Australian wattles on their properties, albeit highlighting financial limitations.

Land users’ perceptions of wattle clearing practices

Differences in values among land user groups and changes in values over time can lead to uncertainties about which management strategies are most suitable to achieve conservation and restoration goals (van Wilgen and Richardson 2014, Darvill and Lindo 2016, Mills et al. 2017, Wartmann and Purves 2018). Hence, understanding the dynamics and interactions within a SES requires ongoing learning and adaptation of management strategies (Biggs et al. 2012, Vaz et al. 2017b). Engaging different stakeholders with varying views and interests is one way of facilitating learning and developing a more commonly shared understanding of management problems and the systems in which they are embedded, especially through social learning opportunities. Provided the process of engaging different stakeholders is well managed, these factors substantially increase the probability of reaching and implementing management strategies in the face of uncertainty (Reyers et al. 2018).

A large proportion of communal land users believed wattle clearing has had positive impacts on their livelihoods and resulted in positive changes in the ecosystem. Such changes included improved water flow, easier access to the landscape, and availability of fuelwood from felled trees, none of which may translate into ecosystem recovery at this stage. However, the availability of essential ecosystem services (ES) such as fuelwood, drinking water for livestock, and sense of place may have important implications in motivating land users to support and participate in IAPs management (Marais and Wannenburgh 2008, Oteros-Rozas et al. 2015, Masterson et al. 2017, Díaz et al. 2018, Young and Kettenring 2020). On the other hand, some respondents in the communal areas highlighted their discontent with the clearing operations because of a lack of follow-up and monitoring of cleared areas in the study area as cleared areas were prone to reinvasion by wattles. This view is not unique to this area; similar views have been raised elsewhere (Jones and Boyd 2011, Rouget et al. 2015, Shackleton et al. 2016, Nsikani et al. 2018a). Indeed, some invasion landscapes are prone to reinvasion, depending on the characteristics of the invading species (including large seed bank and the ability to resprout), the invaded landscape (Le Maitre et al. 2011, Nsikani et al. 2018a, b), and post-clearing management.

Half of the commercial farmers mentioned that their efforts to clear wattle had positively affected their livelihoods. Most important for commercial farmers were the improvements in grazing conditions, water availability, and the premise of the improved economic value of the farm. Some possible reasons that explain the differences in perceptions between land user groups are, first, invasion in commercial farms was not as extensive as in the communal lands. Therefore, it is more feasible to target areas to clear with achievable goals and follow-up actions in mind. Second, commercial farmers are more inclined to prioritize follow-up activities to minimize the reinvasion of cleared areas (Urgenson et al. 2013, Shackleton et al. 2016, 2019e, Potgieter et al. 2019).

Land users’ perceptions of the barriers and enablers to wattle management and stakeholder participation

Research on barriers and enablers to effective management of IAPs is receiving greater attention, as has been documented in some studies in South Africa (Urgenson et al. 2013, Shackleton et al. 2016, Potgieter et al. 2019) and elsewhere (Boy and Witt 2013). In this study, there was little similarity regarding the barriers shared by the two respondent groups. Similarly, in their study, Shackleton et al. (2016) reported significantly varying views among multiple stakeholder groups with regard to barriers that hinder the effective management of an invasive tree species. Barriers mentioned by communal stakeholders were largely associated with natural and socioeconomic factors, whereas commercial farmers only mentioned high cost (economic barrier) as a hindrance to their efforts.

The natural barriers included lack of capacity, fast regrowth, and high rate of spread of wattle. Indeed, species traits and invasiveness often complicate the management of IAPs. These include fast growth rate, high levels of seed production, persistent seed banks, and the ability to resprout, all of which are true for most wattle species (Gallagher et al. 2011, Castro-Díez et al. 2014). Furthermore, research has shown that landscape characteristics influence farmers’ behavior concerning environmental management and their willingness and ability to adopt new practices (Mills et al. 2017, Novoa et al. 2018). For instance, aspects of land structure such as farm size, land use type, dependency on natural resources, amount of non-intensively used land, and the bio-geographical conditions of the landscape can determine land users’ ability and willingness to participate in pro-environmental behavior (Urgenson et al. 2013, Shackleton et al. 2016, Novoa et al. 2018). If there is a large proportion of unused land people are less likely to invest resources and time on such, but rather focus on the portion of the land that is perceived to be productive. In communal areas with vast areas of cropland and underutilized for cultivation, it is not easy to find motivation for land users to control wattle in such areas. Yet, such areas can become the source of wattle spread if not appropriately managed (Scorer et al. 2019, Gouws and Shackleton 2019b, Shackleton et al. 2019d). Linked to the above, some communal farmers felt that the extent of invasion had gone beyond their ability to control and their efforts alone would be futile. This was raised because there were no follow-up plans in some areas, and stakeholders were not consulted before clearing, which led to a lack of coordination between implementers and land users. Moreover, the nature of communal tenure can provide a disincentive to individuals to pro-actively manage the land unless there is a mechanism or institution that brings all the land users together and all participate in the agreed management actions. Such actions are likely to demotivate stakeholders and affect trust and belief in the efforts that are being undertaken.

The results show that time and labor constraints can affect farmers’ environmental behavior. In a rural context, one of the main challenges for effective land management is the loss of human resources, mainly due to youth migration to cities for education and in search of jobs (Ncube et al. 2014, Fay 2015, de la Hey and Beinart 2017, Shackleton et al. 2019d). This could have negative implications when adopting required adaptive measures and monitoring of cleared areas. On the other hand, commercial farmers relied on their farm labor to control wattle spread in the farms.

The economic barrier was a common hindrance identified by the two groups of farmers. Although most commercial farmers implemented control measures on their properties, the high costs associated with clearing operations, including follow-up treatment, can be highly restrictive for individual farmers and communal land users. Second, younger participants from the communal areas mentioned that they were willing to control wattle invasion if some financial incentives were available. Overall, the results highlight the complexity of factors that can hinder conservation efforts in such areas, which are underlined by contextual factors such as high levels of poverty. With high poverty rates, many people in rural areas are more interested in securing income-generating opportunities. Therefore, the program is less likely to receive full support from local land users without clearly defined potential benefits and livelihood opportunities (e.g., agricultural activities on cleared sites) for clearing IAPs and maintaining cleared areas.

Land users’ perceptions of potential incentives and motives for participation

Achieving workable management strategies for IAPs depends on the acceptance, cooperation, and support of implementation actions and policies from all relevant stakeholders, those supporting the use of the species and those supporting its control (Reed et al. 2007, Shackleton et al. 2019b, Young and Kettenring 2020). In this study area, initial clearing operations through the Working for Water program have been successful in some areas. However, lack of follow-up operations and poor engagement of local land users has resulted in the reinvasion of cleared land in other areas.

Despite citing many negative impacts caused by the wattle invasion (Ngorima and Shackleton 2019, Yapi et al. 2023), very few respondents in communal areas voluntarily removed wattle from the landscape. Both the commercial and communal farmers expressed the need for financial incentives, tools, and including fencing of grazing areas. Many commercial farmers believed that some form of financial assistance and supply of arboricides was necessary for them to be able to make meaningful progress in wattle control as the costs of clearing wattle were too high, with farmers spending substantial amounts of money on wattle control. As with many other conservation challenges, societal adaptation to ecosystem degradation requires measures that simultaneously address societal challenges such as poverty and restore biodiversity and ecosystem services (Reed et al. 2007, Mills et al. 2017, Young and Kettenring 2020). Such measures need to be built on a sound understanding of the socioeconomic context, local needs, and aspirations of communities reliant on the ecosystem (Cocklin et al. 2007, Pasquini et al. 2010, Ulvevadet and Hausner 2011).

The results of this study underscore the distinct socioeconomic challenges facing the two land tenure systems. In communal areas, the social-ecological dynamics are mainly influenced by the desire for income and job opportunities. This also highlights how the formal economy is changing livelihood patterns in rural areas, reducing direct dependence on natural resources. Some households now rely on cash income from jobs or remittances from urban relatives. Income generated from natural resources, especially agriculture, forms only a minor part of most households’ average income. As such, natural resource conservation is of diminishing importance as more young people seek to join the labor market elsewhere (Pereira et al. 2014, Shackleton et al. 2019d). In contrast, wealthier commercial farmers are less impacted by factors like low income and poverty, so their needs and demands are more focused on ecological issues. Furthermore, in communal areas where natural resources are shared among land users, if someone voluntarily removes wattles from the landscape, they cannot capture all the benefits of doing so, which becomes a disincentive because others capture a share of the benefits. This lack of incentive leads to minimal conservation efforts. In contrast, commercial farmers operating on privately owned land, have a clear incentive to manage resources efficiently because they will benefit proportionately and directly from such actions.

Implications for management

The findings of this study indicate a need to consider a mix of incentives that may effectively engage land users in IAPs clearing. For instance, barriers identified in this study are often difficult to overcome, but management interventions, where possible, post-clearing land use options, can be tailored to focus on such barriers. First, with a short turnaround time required to control wattle regrowth, it is crucial that follow-up restoration plans are developed in consultation with stakeholders (Ruwanza and Tshililo 2019). This should be done before clearing decisions are taken and consider what follow-up options are available, including allocating funds for follow-up work and post-clearing land use options. In this way, areas of the landscapes that are more important to land users can be prioritized. In cases where costs of follow-up are likely to exceed the initial clearing costs, such a situation warrants restoration interventions. Therefore, further work is needed to better understand the total demand for restoration in the program. There is preliminary evidence that the successful establishment of indigenous vegetation can suppress alien recruitment in some situations (Blanchard and Holmes 2008, Pretorius et al. 2008). Second, the application of arboricide on cleared sites to prevent reinvasion through coppicing or resprouting should be considered. Moreover, the introduction of biological control agents that limit the further spread of IAP populations should be considered (Wilson et al. 2011).

Although most commercial farmers implemented some control measures on their properties, the high costs associated with clearing operations, including follow-up treatment, proved to be highly restrictive for some individual farmers. Commitment in terms of financial resources and buy-in and support of a shared vision by land users is crucial. Buy-in is essential for a landscape approach to clearing, with private landowners often having to commit funds to clear IAPs on their land to reduce the threat of reinvasion of adjoining public land that has been cleared under the mandate of WfW. However, although financial incentives have been effective in achieving some environmental management behavioral change among farmers (Urgenson et al. 2013), these should ultimately be viewed as transient drivers with the aim to create long-term sustainability and cultural change.

In conclusion, the negative impacts of wattles on social-ecological systems in the region are substantial (Gwate et al. 2016, Yapi et al. 2018, 2023, Gouws and Shackleton 2019b, Ngorima and Shackleton 2019) and warrant a more integrated approach. Although wattle clearing operations are currently in place, without proper follow-up operations and engagement of local land users, the problem will continue and may even deteriorate. Unsustainable use and management of natural ecosystems and underuse of former croplands can expose ecosystems to IAPs (Shackleton et al. 2019d). Therefore, novel ways are needed to address factors that may directly or indirectly facilitate invasion by IAPs. An ideal approach would require the involvement of all relevant stakeholders to ensure all social-ecological dimensions influencing the management of IAPs are addressed (Novoa et al. 2018). As a first step, there is a need to establish or strengthen existing local-level institutions such as local government and traditional authorities, responsible for managing natural resources. Second, although management of IAPs in the catchment and elsewhere has been the responsibility of the WfW program, it is essential for other relevant government departments and the private sector to contribute, in particular, to clear areas of high agricultural potential and support the establishment of programs and institutions to enhance sustainable use of ecosystems. Third, prioritization of critical ecosystems such as water source areas for IAP management, both as passages for IAPs and dispersal and as water sources, could prove essential in reducing IAPs spread and getting land user buy-in (Esler et al. 2008).

Linked to the above points, approaches to combating land degradation including addressing the problem of IAPs infestations are currently in place in the Matatiele area through the Umzimvubu Catchment Partnership Programme (UCPP). The UCPP is a multistakeholder program that was formed in 2011 to address severe land degradation in the catchment through the promotion of sustainable land use practices to ensure a continued flow of ecosystem services to people and nature (UCPP 2011). Some of the activities focusing on controlling IAPs include introducing sustainable grazing practices in the communal areas. Through the program, communities receive training in land management including sustainable grazing practices, cattle management, clearing of IAPs and land restoration techniques. The partnership is showing promising outcomes for rural communities that rely on natural resources and livestock rearing for sustenance, as well as in terms of protecting ecosystem integrity of the area (Ntshotsho et al. 2015, Morokong and Blignaut 2020). Although the focus of this study was not the work of the program, there is an opportunity for future research to investigate the success and challenges of such a program. Lessons learned from the UCPP program may be useful in other grassland landscapes as well.

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