Temperate broadleaf and mixed forests

Temperate broadleaf and mixed forest is a temperate climate terrestrial habitat type defined by the World Wide Fund for Nature, with broadleaf tree ecoregions, and with conifer and broadleaf tree mixed coniferous forest ecoregions. These forests are richest and most distinctive in central China and eastern North America, with some other globally distinctive ecoregions in the Caucasus, the Himalayas, Southern Europe, Australasia, Southwestern South America and the Russian Far East. The typical structure of these forests includes four layers. The uppermost layer is the canopy composed of tall mature trees ranging from high. Below the canopy is the three-layered, shade-tolerant understory that is roughly shorter than the canopy. The top layer of the understory is the sub-canopy 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 (Quercus spp.), beeches (Fagus spp.), maples (Acer spp.), or birches (Betula spp.). The term "mixed forest" comes from the inclusion of coniferous trees as a canopy component of some 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. In the Southern Hemisphere, endemic genera such as Nothofagus and Eucalyptus occupy this biome, and most coniferous trees (members of the Araucariaceae and Podocarpaceae) occur in mixtures with broadleaf species, and are classed as broadleaf and mixed forests. Temperate broadleaf and mixed forests occur in areas with distinct warm and cool seasons that give them moderate annual average temperatures: . These forests occur in relatively warm and rainy climates, sometimes also with a distinct dry season.