Taiga or boreal forest covers most of inland Canada, Alaska, and parts of the northern contiguous United States, as well as most of Sweden, Finland, much of Russia, much of Norway and Estonia, and parts of Iceland.
The taiga is a vast forest whose main tree species are spruce, pines, birch, and larches.
It’s a relatively new biome, having only existed for the last 12,000 years, the land covered by the ice sheet or mammoth steppe.
Taiga Facts for Kids
- The taiga biome has a lot of fires
- Taiga is known as the coniferous forest
- Taiga conifer trees are evergreen
- Most of this biome is uninhabited
- During the winter, temperatures can drop below -60°F
- Cold winter months cause many animals to migrate or hibernate
The taiga is the terrestrial biome with the lowest average annual temperatures, with mean annual temperatures generally varying from -5 to 5 °C.
It has a subarctic climate with a large range between seasons, with short summers lasting 1 – 4 months and long winters lasting 5 – 7 months.
Siberian taiga has mild winters but reaches into oceanic climates in the extreme south and west.
In areas with an annual temperature above freezing, there is discontinuous permafrost. In areas with a mean annual temperature below freezing, there is continuous permafrost.
The growing season for plants is slightly longer in the taiga than the climatic definition of summer.
The longest growing season can be found in coastal areas of Scandinavia and Finland, while the shortest growing season can be found at the northern taiga – tundra ecotone.
High latitudes have long summer days and short winter days, but the polar night is mid-winter.
Throughout the year, the taiga experiences relatively little precipitation, with some areas experiencing snow and fog.
The fog in low-lying areas of the Arctic prevents sunshine from getting through to plants, allowing for dense vegetation growth, especially large trees.
Taiga soils tend to be young and low in nutrients because of the cold climate and the lack of deciduous trees and grazing animals.
In a forest with a moist climate, leaves and moss can remain on the forest floor for a long time, limiting their organic contribution to the soil.
As North America and Asia were once connected by the Bering land bridge, many animal and plant species colonized both continents. These differ regionally, typically with each genus having several distinct species, each different occupying regions of the taiga.
There are two types of taiga in the southern part of the taiga: lichen woodland and sparse taiga, with far-spaced trees and lichen ground cover. In the northernmost taiga, the forest is stunted in growth form and often ice pruned.
The Taiga spruce forest of the Kenai National Wildlife Refuge, Alaska, is dominated by black spruce, tamarack larch, and balsam fir.
Trees in the taiga have shallow roots, harden their biochemistry, and tend to have downward-drooping limbs so that they shed snow.
Evergreens cannot generate energy from photosynthesis when the sun is low on the horizon, and because of their dark green needles, they absorb more sunlight.
Coniferous forests are the predominant species, but broadleaf trees, such as birch, aspen, willow, and rowan, also occur. Periodic stand-replacing wildfires allow sunlight to invigorate new growth on the forest floor.
Coniferous trees dominate the taiga biome. Spruces are dominant in North America, Scandinavia, and western Russia; Scots pine is dominant in Russian Far East, while larch is dominant in eastern Siberia.
The boreal forest of Canada includes 85 species of mammals, 130 species of fish, and an estimated 32,000 species of insects. Reptiles and amphibians are hard to find because they must adapt to extreme temperatures and cold water.
Large herbivorous mammals, such as moose, reindeer, caribou, and wood bison, live in the taiga. Small mammals are able to survive the harsh winters, and predators are well adapted to travel long distances in search of prey.
More than 300 species of birds breed in the taiga, including Siberian thrush, white-throated sparrow, black-throated green warbler, and Siberian golden eagle.
The fire regime of a boreal forest describes the frequency and size of fires, and the average time it takes to burn the area equivalent to its total area is its fire rotation.
High-intensity crown fires dominate the boreal forest and severe surface fires. Fire cycles are long in the western boreal forest.
Amiro et al. (2001) predicted increased fire activity for western Canada but less fire for eastern Canada.
Fire has always played an important role in the boreal forest, and evidence of this is the patchwork mosaic of forest stands, the prevalence of fire-adaptive morphologic and reproductive characteristics of many boreal plant species, and their association with fire.
The former Soviet Union protected the Russian taiga forest from logging, but with the collapse of the Union, the forest has been harvested for timber.
Only about eight percent of Canada’s forest is protected. The forest is destroyed in large blocks and replanted with monochrome seedlings, destroying the forest ecosystem for many years.
The taiga stores enormous quantities of carbon. It is home to unique flora and stores more carbon than all other forests combined.
Taiga areas may be protected by prohibiting logging, mining, oil and gas production, and other forms of development. Two Canadian provinces have promised to protect at least half of their northern boreal forest but have not taken any action.
Lichen woodland vegetation is influenced by a cycle of large, damaging fire, and the vegetation recovers from these fires through vegetative reproduction, propagules, and self replacement.
The vegetation is propagated through one of four pathways: self replacement, species-dominance relay, species replacement, or gap-phase self replacement.