A boreal forest, also known as a taiga, is a biome characterized by coniferous forests consisting mostly of pines, spruces, and larches. It is the worlds largest land biome and spans across the northern hemisphere, including Canada, Alaska, Scandinavia, Finland, Russia, and parts of China and Japan. The boreal forest is usually divided into three subzones in Canada, Scandinavia, and Finland: the high boreal (northern boreal/taiga zone), the middle boreal (closed forest), and the southern boreal, a closed-canopy, boreal forest with some scattered temperate, deciduous trees among the conifers.

Boreal forests have evolved under the constraints of a short growing season and severe winters during which snow cover may last for several months. They are characterized by a low diversity of tree species, of which gymnosperms such as Abies, Larix, Pinus, and Picea species usually dominate, with varying proportions of angiosperm Populus, Betula, and Alnus species.

The boreal forest plays an enormous role in slowing the effects of climate change, as it stores almost twice as much carbon as tropical forests. It is also home to numerous Indigenous communities that have relied on these forests for millennia. The Canadian boreal, which is the largest intact forest left in the world, is critical to North Americas bird population, serving as the nesting grounds for more than three billion birds.

In summary, a boreal forest is a vast coniferous forest biome that spans across the northern hemisphere and is characterized by a low diversity of tree species. It plays a crucial role in slowing the effects of climate change and is home to numerous Indigenous communities and wildlife species.