Temperate broadleaf and mixed forests
Mixed forests are a temperate
In geography, temperate or tepid latitudes of the globe lie between the tropics and the polar circles. The changes in these regions between summer and winter are generally relatively moderate, rather than extreme hot or cold...

 and humid biome
Biomes are climatically and geographically defined as similar climatic conditions on the Earth, such as communities of plants, animals, and soil organisms, and are often referred to as ecosystems. Some parts of the earth have more or less the same kind of abiotic and biotic factors spread over a...

. The typical structure of these forests includes four layers. The uppermost layer is the canopy
Canopy (forest)
In biology, the canopy is the aboveground portion of a plant community or crop, formed by plant crowns.For forests, canopy also refers to the upper layer or habitat zone, formed by mature tree crowns and including other biological organisms .Sometimes the term canopy is used to refer to the extent...

 composed of tall mature trees ranging from 33 to 66 m (100 to 200 feet) high. Below the canopy is the three-layered, shade-tolerant understory
Understory is the term for the area of a forest which grows at the lowest height level below the forest canopy. Plants in the understory consist of a mixture of seedlings and saplings of canopy trees together with understory shrubs and herbs...

 that is roughly 9 to 15 m (30 to 50 feet) shorter than the canopy. The top layer of the understory is the sub-canopy which is composed of smaller mature trees, saplings, and suppressed juvenile canopy layer trees awaiting an opening in the canopy. Below the sub-canopy is the shrub
A shrub or bush is distinguished from a tree by its multiple stems and shorter height, usually under 5–6 m tall. A large number of plants may become either shrubs or trees, depending on the growing conditions they experience...

 layer, composed of low growing woody plants. Typically the lowest growing (and most diverse
Biodiversity is the degree of variation of life forms within a given ecosystem, biome, or an entire planet. Biodiversity is a measure of the health of ecosystems. Biodiversity is in part a function of climate. In terrestrial habitats, tropical regions are typically rich whereas polar regions...

) layer is the ground cover or herbaceous
A herbaceous plant is a plant that has leaves and stems that die down at the end of the growing season to the soil level. They have no persistent woody stem above ground...



Characteristic dominant broadleaf trees in this biome include oaks (Quercus spp.), beeches (Fagus
Beech is a genus of ten species of deciduous trees in the family Fagaceae, native to temperate Europe, Asia and North America.-Habit:...

spp.), maples (Acer
Acer is a genus of trees or shrubs commonly known as maple.Maples are variously classified in a family of their own, the Aceraceae, or together with the Hippocastanaceae included in the family Sapindaceae. Modern classifications, including the Angiosperm Phylogeny Group system, favour inclusion in...

sap.), and birches (Betula spp.). The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of these forests. Typical coniferous trees include: Pines (Pinus spp.), firs (Abies spp.), and spruces (Picea spp.). In some areas of this biome the conifers may be a more important canopy species than the broadleaf species.


Temperate broadleaf and mixed forests occur in areas with distinct warm and cool season, which give it a moderate annual average temperature (3 to 15.6 °C). These forests occur in relatively warm and rainy climates, sometimes also with a distinct dry season
Dry season
The dry season is a term commonly used when describing the weather in the tropics. The weather in the tropics is dominated by the tropical rain belt, which oscillates from the northern to the southern tropics over the course of the year...

. A dry season occurs in the winter in East Asia and in summer on the wet fringe of the Mediterranean climate
Mediterranean climate
A Mediterranean climate is the climate typical of most of the lands in the Mediterranean Basin, and is a particular variety of subtropical climate...

 zones. Other areas have a fairly even distribution of rainfall; annual rainfall is typically over 600 millimetres (24 inches) and often over 1500 millimetres (60 inches). Temperatures are typically moderate except in parts of Asia such as Ussuriland where temperate forests can occur despite very harsh conditions with very cold winters.



See also

  • Forest
    A forest, also referred to as a wood or the woods, is an area with a high density of trees. As with cities, depending where you are in the world, what is considered a forest may vary significantly in size and have various classification according to how and what of the forest is composed...

  • Kuchler plant association system
  • Temperate deciduous forest
    Temperate deciduous forest
    A temperate deciduous forest, more precisely termed temperate broadleaf forest or temperate broadleaved forest, is a biome found in North America, southern South America, Europe, and Asia. A temperate deciduous forest consists of trees that lose their leaves every year...

  • Trees of the world
    Trees of the world
    * Trees of The Americas** Trees of Canada*Trees of North America** Trees of the Caribbean Basin* Trees of Australasia** List of trees native to New Zealand** Trees of Australia*Trees of Europe** Trees of Britain and Ireland** Trees of Denmark...

External links

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