Mixed forests are a temperate and humid biome. The
typical structure of these forests includes four layers. The uppermost layer is
the canopy composed of tall mature trees ranging from 30 to 61 m (100 to
200 ft) high. Below the canopy is the three-layered, shade-tolerant
understory that is roughly 9 to 15 m (30 to 50 ft) 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 layer, composed of low
growing woody plants. Typically the lowest growing (and most diverse) layer is
the ground cover or herbaceous layer.
In the Northern hemisphere, characteristic dominant broadleaf trees in this biome include oaks, beeches, maples, and birches. The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of these forests. Typical coniferous trees include: Pines, firs, and spruces. In some areas of this biome the conifers may be a more important canopy species than the broadleaf species. In the Southern hemisphere, endemic genera such as Nothofagus and Eucalyptus occupy this biome.
Trees
In the Northern hemisphere, characteristic dominant broadleaf trees in this biome include oaks, beeches, maples, and birches. The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of these forests. Typical coniferous trees include: Pines, firs, and spruces. In some areas of this biome the conifers may be a more important canopy species than the broadleaf species. In the Southern hemisphere, endemic genera such as Nothofagus and Eucalyptus occupy this biome.
Climate
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 (37 to 60 °F).
These forests occur in relatively warm and rainy climates, sometimes also with
a distinct dry season. A dry season occurs in the winter in East
Asia and in summer on the wet fringe of the Mediterranean climate zones.
Other areas have a fairly even distribution of rainfall; annual rainfall is
typically over 600 mm (24 in) and often over 1,500 mm
(59 in). 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.