Wilding conifers, also known as wilding pines, are invasive trees in the high country of New Zealand. Millions of dollars are spent on controlling their spread. In the South Island, they threaten 210,000 hectares of public land administered by the Department of Conservation. They are also present on privately owned land and other public land such as roadsides. The wilding conifers are considered to be a threat to biodiversity, farm productivity and to landscape values. Since they often invade tussock grasslands – which are characterised by low-lying vegetation that is considered to be a natural environment – the tall trees become a prominent and unwanted feature.