Lehtikasvuston

Lehtikasvuston is a Finnish term used in ecology and forestry to describe the foliar vegetation layer of a plant community. It comprises leaves from trees, shrubs, and, in some contexts, herbaceous plants that form a continuous or patchy cover within the vertical structure of the vegetation. The layer plays a central role in intercepting light, driving photosynthesis, and shaping the microclimate, soil moisture, and understory conditions.

In practice, lehtikasvuston is assessed with measures such as leaf area index (LAI), canopy cover percentage, and leaf biomass. It is a key element in understanding forest productivity, succession, disturbance responses, and carbon cycling, and it informs silvicultural planning by indicating how the leafy layer develops under different management actions.

The characteristics of lehtikasvuston vary with forest type, age, disturbance history, and season. In boreal and temperate forests common to Finland, the foliar layer shows seasonal changes due to leaf phenology; deciduous stands shed leaves, reducing light interception in winter, whereas evergreen stands retain foliage year-round. Distinctions are often made between the lehtikasvuston and other vertical layers, such as the woody stem layer and ground vegetation, to describe the overall vertical structure of the stand and its habitat provisioning for wildlife.