Invasive alien plant species (IAPs) are species whose introduction and/or spread outside their natural distribution threaten biological diversity. They are non-native to an ecosystem and may cause economic or environmental harm.

According to the National Environmental Management: Biodiversity Act (NEMBA), Category 2 IAPs are plant species with commercial or utility value which may only be grown under certain conditions. Examples of these species are Beefwood trees used as windbreaks, Pines for wood manufacturing, or Gum trees for honey production. However, this is only true if the current landowner possesses a demarcation permit and ensures that the IAPs do not spread beyond the demarcated area and that they are not planted within 30 metres of the 1:50 year flood line of watercourses, lakes, dams, and wetlands.

A permit application form needs to be completed and sent to the Department of Agriculture, Land Reform and Rural Development (DALRRD) along with an IAP clearing plan that contains a map indicating the location of the stands as well as a worksheet with the following information:

i. Name of species (e.g., Beefwood trees – Casuarina cunninghamiana)
ii. Their use (e.g., Windbreaks),
iii. Density,
iv. Maturity and
v. Methods of controlling further spread.