Lehtimetsät

Lehtimetsät are forests in which broadleaf deciduous trees dominate and that shed their leaves seasonally. The term is used in Finnish to describe temperate deciduous forests, which occur in different parts of Europe and contrast with boreal coniferous forests and with mixed or evergreen forests. In winter, a lighter canopy and a rich ground layer are typical of these forests, reflecting the seasonal cycle of leaf drop and regrowth.

The species composition of lehtimetsät varies with climate and soil. Common deciduous genera include birches (Betula spp.), aspen (Populus tremula) and alders (Alnus spp.). In milder or more southern parts of Europe, oaks (Quercus spp.) and lindens (Tilia spp.) can contribute substantially to the canopy. The understory is typically diverse, with shrubs and a variety of herbaceous plants, mosses and ferns that take advantage of the seasonal light regime and the nutrient-rich leaf litter.

Ecology and function: lehtimetsät support high biodiversity and complex structural variation, providing habitats for many birds, mammals, insects and ground-dwelling invertebrates. The leaf litter and soil organic matter drive nutrient cycling, while the seasonal changes influence phenology and animal life cycles. Disturbance regimes, such as gaps created by windthrow or small-scale logging, help maintain regeneration and species diversity.

Geographical distribution and use: in Finland, lehtimetsät are primarily found in southern and central regions and in some coastal areas, with broader distributions across temperate Europe. They are valued for timber, recreation and biodiversity. Management often aims to maintain a mosaic of age classes, retain mature trees and deadwood, and preserve the ecological integrity of the canopy and understory.

Conservation: some stands are protected or managed under sustainable forest plans to safeguard habitat for lichens, invertebrates, birds and mammals. Threats include land-use change, fragmentation, climate change and invasive species.