For decades, South Africa has been heavily infested by invasive alien plants. As a result there is concern over the increasing rate at which the alien plants are replacing indigenous vegetation. Another concern regarding the invasive alien plants is the indirect stress they pose on the environment due to their excessive water consumption. As a result of this, government of South Africa, through the Conservation of Agricultural Resources Acts (43 of 1983) and other environmental legislation, mandates and encourages the removal of invasive alien plants from the landscapes of South Africa. The need for removal of these invasive alien plants led to the formation of the Working for Water Programme (WfW), which is based on a novel approach to environmental management. It contends that the invasion of ecosystems by invasive alien plants could have detrimental effects on water yields from catchment areas, and that employing people to deal with the problem could both protect this vital resource and provide employment and upliftment in poor rural communities. It has been suggested that the supply of information to the public about invasive alien plants is generally poor, to the extent that many people are the causal agents of these plants entering their communities (McNeely 1999). If this lack of awareness is the case, then understanding the drivers of local knowledge which will feed into public awareness is essential to change public perceptions and values surrounding invasive alien plants. It is important to understand local knowledge in order to determine gaps in information transfer and enable them to make decisions that are grounded in local cultural interpretations of place and their environment (Ebohon et al 2000). It is also important to ii understand what the local communities know and what they need to know about these invasive alien plants. This study is premised on developing an understanding of local knowledge and perceptions about invasive alien plants. The assumption is that those involved in the programme would display positive values towards the environment. It is also assumed that those involved in the programme have developed their local/traditional knowledge of invasive alien plants through the educational component of WfW programme. A case study approach of Upper Illovu Working for Water project was adopted. The research was carried out by means of questionnaire interviews. The respondents were drawn from Indaleni community in Richmond, KwaZulu-Natal. Thirty respondents were interviewed and this was inclusive of the field workers, contractors, project manager and people who were not involved in the project but from the same community. Those not involved in the project were used as a control group. Five objectives were utilized to investigate the aim of this study. They were to: a) Determine the respondents’ relationship to, and perceptions of the Upper Illovu WfW project b) Establish the respondents’ understanding and perceptions about the levels of invasive alien plants in the area c) Determine the respondents’ knowledge and perceptions pertaining to prevention of the spread of invasive alien plants iii d) Establish the respondents’ competencies in controlling and managing invasive alien plants and e) Establish the respondents’ perceptions about the project’s ability to deliver on its objectives. The results of this study indicate that most of the respondents were aware of the Upper IIlovu WfW project and its ecological and social upliftment objectives. The pattern of the responses was such that those that did not participate in the project (control group) were for the most part not sure about their responses. Although those who participated in the project displayed better knowledge of issues concerning invasive alien plants, there were many occasions when they failed to provide some responses without being prompted – given clues or examples. To conclude, there was, therefore, a significant knowledge gap about invasive alien plants and information pertaining to them between the two groups. The implications are that those involved with the project must have received some form of information through public awareness about invasive alien plants. That is their traditional knowledge about these invasive plants has been developed by the education from the programme, WfW. But most importantly, the programme remains a key for economic reasons from the perspective of the participants. The need for constant improvement and development of local knowledge regarding these invasive alien plants is important in dealing with their spread and management of their effects on the environment. / Thesis (M.Env.Dev.)-University of KwaZulu-Natal, Pietermaritzburg, 2010.

According to Baker (1955), success of plant invasions can be attributed to autogamous breeding systems and generalist pollination systems. A test of Baker's rule was carried out on 19 invasive alien plant species in KwaZulu-Natal, South Africa. Natural levels of fruit set in these plants was high (median= 71.5% fruit set per plant). Breeding system experiments for 18 species showed that 17% of the species are allogamous, 72 % are autogamous and 11% are apomictic. This contrasts markedly with a general flora of 1472 species in which 65% are allogamous, only 14% are autogamous, and 21% are apomictic. Because the breeding systems of the alien species were largely autogamous, pollinators make only a small contribution to the overall reproductive success. Seventy one percent of the 14 alien species for which pollinators were obtained were pollinated by honeybees, which are super-generalists and ubiquitous in a generalist pollination systems. However, some species showed pre-adaptation to relatively specialized pollination systems, involving hawkmoths, butterflies and Xylocopa bees respectively. Thus, alien plants were not visited by a wide range of insects, but rather showed pre-adaption to one or more pre-existing guilds in the new habitat. Pollen limitation experiments showed no evidence that reproductive success in populations of the species is limited by pollen availability. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2001.

The problems posed by alien invasive plants to our environment and the need for clearing and control has been highlighted by the Working for Water (WFW) programme. Alien plant control requires careful planning, including budgeting. To date, costing and budgeting in alien plant control has largely been a combination of experience on the part of weed 'experts', coupled with much guess work. Weed controllers have through experience calculated the amount of time (or the work rate), recorded as labour days, required for different control actions of different weed habits. These work rates are for weed clearance under ideal conditions and do not take into account the effect of factors such as gradient, access and distance to the weed infestation. Factors affecting the work rate has been researched and modelled by researchers in both alien plant control and the timber industry. While the existing work rate model is useful in its present theoretical state, the model may be improved upon to make it more practical and applicable to the varying conditions of different areas. This research built on existing theoretical research on alien control work rates, and concentrated on two main areas: the adaption and incorporation of the existing research on work rates into a Geographical Information System (GIS), and the creation and demonstration of a Spatial Decision Support System (SDSS) for the management of alien plant control. The eMpofana river in the KwaZulu-Natal midlands was selected as the study area, as there was an existing alien plant control programme. Initially all factors, such as slope, access to weed infestations, terrain and penetrability of infestations, affecting the work rate in the research area were identified. An existing work rate model was then modified to account for the conditions of the research area. Regression analysis was used to derive the relationship between the various factors affecting work rate, creating a work rate model applicable to the study area. Using the results of the regression analysis together with work rate figures adapted from an existing alien plant control programme, a SDSS for alien plant control along the eMpofana River was created. The use of the work rate model and the SDSS in the development of weed control programmes was demonstrated by examining four different management approaches, each having a different management objective . The SDSS provides a spatial component to weed control planning and costing that has thus far not existed. What this research has achieved is the advancement of an alien control work rate model from a theoretical to a more realistic costing process. While some factors affecting work rate may not have been accounted for, the model does address the present inaccuracies in labour costing, and ultimately alien plant control costing. The research has highlighted the disadvantages of GIS in terms of affordability and expertise. The model has wider uses than the eMpofana River, and is the ground work for the further development of a user friendly model applicable throughout South Africa. More effective project budgeting will decrease the likelihood of project failure and this will directly benefit long-term weed control efforts. / Thesis (M.Sc.)-University of Natal, Pietermaritzburg, 2000.

The aim of the study was to find benefits derived from the natural propagation and the use of guava plants and fruit by people living in rural areas of KwaZulu-Natal, looking at guava as a source of food, income, medicinal uses, shade, a source of fuel and use for agricultural purposes like fencing; and also assessing Conservation of the Agricultural Resource Act (CARA), Act 43 of 1983 relating to guava plant as invasive species. The Act states that all alien invader species and weeds should be controlled or removed depending on the category. CARA states that plants in category one are declared as alien invasive plants and are not allowed to grow on the land or appear on the water surface. Plants under this category may not be transported or allowed to disperse e.g. Psidium x durbanensis (Durban guava). Category two plants are invader species that have a potential value, plants that are used by the people as a source of income and food. These species can be retained if they grow in special areas demarcated for the purpose (an orchard). If these species are found outside demarcated areas they are to be removed e.g. Psidium guava (guava). Category three species are mostly plants with ornamental value which are not allowed to occur anywhere unless they were already in existence when the regulation came into effect e.g. Psidium guineense (brazillian guava) and Psidium cattleianum (strawberry guava). The study focused on selected areas of KwaZulu-Natal,: Umgungundlovu district municipality (Richmond local municipality) and Uthungulu district municipality. Richmond represented the midlands areas and Uthungulu the coastal areas to reflect two different areas of KwaZulu-Natal. To investigate this study the researcher used telephonic interviews with 23 Extension officials, questionnaires to guide focus group discussions which were conducted with 28 community groups that were involved in guava usage. Informal observation surveys were also carried out with five markets (stall holders) selling guava and guava products. Informal observations in two supermarkets and two home industries were also conducted. The results showed that people in rural areas still use this resource (guava) as a source of fuel (wood), medicine (especially the leaves and bark), fruit for own consumption (either processed or raw) and income generation. The impact of the legislation on rural poor communities is negative as guavas sustain livelihoods and the costs of applying for permits are prohibitive. People are illiterate yet they have to apply for special permits to plant this useful species because the regulation stipulates that guava plants must be controlled if dispersed outside demarcated areas. / Thesis (M.Sc.)-University of KwaZulu-Natal, Pietermaritzburg, 2008.