Deciduösa

Deciduösa (often rendered as deciduous) refers to plants that shed all or most of their leaves seasonally. In temperate climates this typically occurs annually in autumn, while in tropical regions leaf fall can align with a dry season or drought period. The strategy contrasts with evergreen plants, which retain leaves year-round.

Leaf shedding occurs through abscission, a developmental process in which cells at the leaf base form an abscission layer, detaching the leaf with minimal damage to the stem. Hormonal changes involving auxins and ethylene, often triggered by shorter day length and cooler temperatures (or drought), initiate senescence and abscission.

Autumn color changes are caused by degradation of chlorophyll and the unmasking and production of pigments such as carotenoids and anthocyanins. The timing and intensity of leaf fall depend on species, climate, and soil moisture, and may influence habitat structure and nutrient cycling through leaf litter.

Deciduösa plants dominate many temperate forests, including many oaks, maples, beeches, and birches. In tropical regions, a large number of species shed leaves during long dry seasons, giving rise to tropical dry forests and savannalike communities. Some species are semi-deciduous, dropping leaves only during periods of extreme drought or cold.

Human uses of deciduous trees include timber, ornamentals, and shade. Understanding deciduousness helps explain seasonal patterns in biodiversity, phenology, and climate interactions.