What are huge subarctic evergreen forest?

The taiga, also known as the boreal forest or snow forest, is a huge subarctic evergreen forest that encircles the globe north of the 50th parallel. As of 2000, this terrestrial ecoregion, the largest on Earth after the tundra , was estimated to cover 11.2 million square kilometers (4.3 million square miles) of coniferous and mixed wilderness across Europe, Asia, and North America.