One of the Ōhau Conservation Trust’s biggest concerns is the spread of wilding trees. The term wilding simply means spreading by self-seeding, which many species in the Mackenzie country do readily.
Pines and larch in particular, seed and grow so thickly that they obliterate everything else, and the Trust views conifers as a particular threat to the local beech forest and tussock grasslands. Most of the Trust’s workdays concentrate on removing conifer seedlings. Rowans, silver birch, poplars and others are also wilding in the Lake Ōhau valley.
Wilding pines spread very easily throughout the open tussock lands of the Ōhau area. As a result, they are creating a major intrusion and modifying the natural ecosystem of the area. The Trust organises regular working bees to remove wilding trees.