serotiny

Serotiny is an ecological adaptation in which seeds or fruits are retained for an extended period and released in response to an environmental trigger, most commonly fire. In serotinous species, seed release is delayed until conditions following disturbance become favorable for establishment, such as reduced competition and increased nutrient availability in post-fire soils.

Mechanisms of serotiny vary among plant groups. In many conifers, resin-sealed cones remain closed for years and only open when exposed to the heat of a wildfire, releasing seeds into a nutrient-rich ash bed. Some hardwoods and Proteaceae, such as Banksia and Grevillea, release seeds from follicles or capsules after exposure to heat or smoke. Seeds may be stored in the canopy as a "standing seed bank" or remain on the plant until disturbance triggers release.

Ecological significance and patterns. Serotiny is particularly common in fire-prone ecosystems, where post-fire regeneration can be more successful than establishment after undisturbed conditions. It represents a convergence of evolutionary strategies to synchronize seed release with favorable environmental conditions. The degree of serotiny can vary within and among populations, ranging from obligate serotiny (fire necessary for release) to facultative or weak serotiny (release occurs with other triggers or at intervals).

Implications for management and conservation. Fire regime changes due to climate change, human activity, or altered land use can affect serotinous species by altering the timing and frequency of seed release. In some systems, prescribed burns or careful fire management are used to maintain serotinous populations and promote regeneration, while in others, excessive fire can destroy the stored seed bank.