Auditors should familiarise themselves with the different types of invasive alien plants (IAPs) that are commonly found on farms, and their different categories as defined by the National Environmental Management: Biodiversity Act 10 of 2004 (NEMBA). With this as a foundation, they should be able to accurately assess IAP control plans for compliance and identify where permits for a restricted activity may be required.

Invasive alien plant (IAP) species refers to plants that are not native in a country or region and have been brought in from another. These plants have a significant negative impact on the environment by causing direct habitat destruction, reducing the availability of water, and increasing the risk and intensity of wildfires. Therefore, the monitoring and eradication of these species are governed by South African legislation. According to NEMBA Regulation 75, all landowners are under legal obligation to control the IAP species present on their properties.

IAP Control Plans

For properties where IAPs are present and the total property is larger than one (1) ha, auditors should confirm whether the site is in possession of an IAP control and monitoring plan.

The Alien and Invasive Species (AIS) Regulations of 2014 list four different categories of IAPs that must be managed, controlled, or eradicated. Auditors should ensure that IAP control plans identify and classify the IAP species present on the property according to these categories, as this will have an impact on which species should be prioritised for clearing first. The categories are as follows:

  • Category 1a: Most harmful species which require immediate action to control and to eradicate. Any form of trade or planting is strictly prohibited.
  • Category 1b: Invasive species that must be controlled and, wherever possible, removed and destroyed. Any form of trade or planting is strictly prohibited.
  • Category 2: Invasive species or species deemed to be potentially invasive, for which a permit is required to carry out a restricted activity. This category includes commercially important species such as pine, wattle, and gum trees.
  • Category 3: Invasive species that may remain in prescribed areas or provinces. Further planting, propagation or trade is, however, prohibited.

Since Category 1a species (such as Kangaroo wattle; Cane cactus; Scotch broom etc.) are deemed to be the highest risk, in most cases they should be the species prioritised for clearing, followed by Category 1b, 2, and 3 (depending on site-specific risk factors such as density, maturity and location). A suitable IAP control plan should contain a map of IAP coverage, as well as a worksheet with the following minimum information:

  • Dominant IAP species present and their relevant categories
  • Density
  • Maturity
  • Methods of clearing

Control plans should be site-specific and generic plans should not be accepted. Auditors should ensure that IAP control plans prioritise mountain catchment and riparian areas, as well as areas that pose a high fire risk for clearing. Control plans should also prioritise lighter infested areas in order to prevent the build-up of seed banks.


Category 2 IAPs are deemed to be potentially invasive and may only be cultivated under special circumstances, for example Beefwood trees (Casuarina cunninghamiana) used as windbreaks between orchards, and Gum trees (Eucalyptus spp.) used for honey production. According to NEMBA, the cultivation of these plants is a restricted activity and therefore a permit is required. Where Category 2 species are cultivated, a demarcation permit is required if a landowner wants to retain these plants for commercial purposes. Demarcation permits for retaining IAP species are issued by the Department of Agriculture, Land Reform and Rural Development (DALRRD). Auditors should be able to identify Category 2 IAP species, and where they are present on a property, auditors should confirm the legality of cultivating these species by reviewing the relevant permits during the document review process. If the site is found to be non-compliant, management should apply for a demarcation permit from the DALRRD.