Nature and EnvironmentExplainer: What are old-growth forests? To view this video please enable JavaScript, and consider upgrading to a web browser that supports HTML5 videoNature and Environment08/22/2019August 22, 2019The oldest trees in the world can be found in the rainforests of New Zealand, where whole areas are as yet untouched by humans. The world's forests are massive sources of fresh water and also important carbon sinks. But they're under serious threat. https://p.dw.com/p/3OGGXAdvertisement