Common (Translated Scientific) Name: Warm Temperate Forest & Woodland Formation
Colloquial Name: Warm Temperate Forest & Woodland
Hierarchy Level: Formation
Type Concept: Warm Temperate Forest & Woodland is found in North America (Mediterranean Basin and Mediterranean of California, the warm, dry interior of Great Basin and Madrean regions, and warm-temperate regions of the Southeastern Coastal Plain), Chile, South Africa, Australia, India and Southeast Asia. The climate is mild with mostly frost-free and often rainy winters, temperate-humid springs, and hot-dry summers. The vegetation varies from (a) dominance by broad-leaved evergreen trees, sometimes with dwarfed stems, and microphyll to small mesophyll leaves, with varying levels of sclerophylly (Mediterranean) to (b) various combinations of broad-leaved deciduous, broad-leaved evergreen or needle-leaved evergreen conifer trees. Natural disturbances include wind and fire.
Diagnostic Characteristics: Broad-leaved evergreen trees, sometimes with dwarfed stems, microphyll to small mesophyll leaves, sclerophyllous (Mediterranean); or various combinations of broad-leaved deciduous, broad-leaved evergreen or needle-leaved evergreen conifer trees. Mild (mostly frost-free) winter, temperate humid spring, hot-dry summer, and mild, often dry autumn seasons. Rainy season in winter and dry summers (Mediterranean).
Rationale for Nominal Species or Physiognomic Features:
Classification Comments: The warm-temperate Mediterranean regions around the world typically contain both the classic Mediterranean scrub (2.B.1. Mediterranean Scrub & Grassland Formation (F038)), and the forests and woodlands included here. Cool-temperate and warm-temperate forests may be difficult to distinguish, but cool-temperate forests are more strongly dominated by broad-leaved deciduous trees, and broad-leaved evergreen trees are essentially absent. Braun (1950) includes at least parts of these warm-temperate forests in her "Deciduous Forest Formation" (the "Southeastern Evergreen Forest Region"), but briefly notes a "Subtropical Broad-leaved Evergreen Forest" that includes central Florida southward.
Various ecoregional treatments recognize the distinct vegetation and climate of the warm-temperate region, e.g., Brown et al. (1998) separates cool-temperate from warm-temperate vegetation. Walter (1985) recognizes two warm-temperate biomes, the "Zonobiome of the Winter-Rain Region with an Arid-Humid Climate and Sclerophyllic Woodlands" (Zone IV) and the "Zonobiome of the Warm-Temperate Humid Climate" (Zone V), distinct from the cool-temperate biome "Zonobiome of the Temperate-Nemoral Climate" (Zone VI) and the boreal biome "Zonobiome of the Cold-Temperate Boreal Climate" (Zone VIII). Similarly, Schultz (1995) recognizes the two warm-temperate regions, which he refers to as: "Mediterranean-Type subtropics" (with world distribution shown in his Figure 129) and "Humid subtropics" (with world distribution shown in his Figure 171). We prefer the term warm-temperate to subtropics. Schultz states that "apart from the driest sites and those with lowest nutrient contents, all the regions of the Mediterranean-Type subtropics were originally covered by forests of mostly evergreen sclerophyllous species of trees" and in the European Mediterranean region, these were mostly evergreen oak, such as Quercus ilex. Today, many of these regions are more typically dominated by sclerophyllous shrub formations, as described in 2.B.1 Mediterranean Scrub & Grassland Formation (F038).
Similar NVC Types:
F008 Cool Temperate Forest & Woodland, note: "More strongly dominated by broad-leaved deciduous trees; broad-leaved evergreen trees essentially absent. Frost regularly occurs, with snow common in the northern parts of the regions."
F012 Temperate Grassland & Shrubland, note: "Open woodlands or tree savannas, with grassy or shrubby understories, and with trees 10% cover or more are placed in 1.B.1 ~Warm Temperate Forest & Woodland Formation (F018)$$,but may have strong floristic similarities to grasslands."
F026 Temperate Flooded & Swamp Forest, note: "1.B.1 ~Warm Temperate Forest & Woodland Formation (F018)$$ typically contains well-drained soils and lacks any aquatic vegetation, peat or muck layer."
F003 Tropical Dry Forest & Woodland, note: "Broad-leaved evergreen trees may be common in 1.B.1 ~Warm Temperate Forest & Woodland Formation (F018)$$, comparable to 1.A.1 ~Tropical Dry Forest & Woodland Formation (F003)$$ (i.e., evergreen leaves are typically small), but deciduousness in Warm Temperate Forest & Woodland is caused by frost, and types are found north or south of 23?N and S latitude."
F038 Mediterranean Scrub & Grassland, note: "The vegetation is more commonly scrub-shrub, typically sclerophyllous, or with open (sometimes annual-dominated) grasslands and forb meadows. Combinations of dwarf scrubby trees <2 m tall with low shrubs may grade into Warm Temperate Forest."