Relationships of fire, tree growth and climate: a dendrochronological study of Scots pine in hemiboreal forests of Lithuania

Lithuanian hemiboreal Scots pine ( Pinus sylvestris L. ) forests have historically been shaped by fire, forming open multi-cohort stands, yet fire suppression and high-yield wood production have simplified stand structure, species composition and forest resilience. This study explores the fire history of six multi-cohort Scots pine hemiboreal forest sites as a step towards developing Closer-to-Nature forest management practices. Applying a dendrochronological approach, we analysed, i) tree rings with fire scars to establish the local fire history, ii) the effects of fire events on tree ring growth, iii) seasonal climate effects on fire events, and iv) correlations between tree ring growth and yearly climate indices. Results revealed median fire intervals of 5 to 11 years across sites, indicating frequent fire occurrence. Tree-ring analysis revealed contrasting post-fire growth trajectories, ranging from immediate release to prolonged suppression and delayed recovery, underscoring the complexity of tree ring growth post forest fire events. Seasonal climate anomalies associated with fire event years were rare, site-specific, and dispersed across seasons both before and after the fire years, thus indicating inconsistent regional climatic signals. Correlation analysis showed weak and non-significant relationships between Scots pine growth and both short- and long-term drought indices, while precipitation and temperature exerted stronger but highly site-specific effects. Our findings highlight the incongruities between current forest management and the historical role of fire in shaping Scots pine forest ecosystems, underscoring the need for their reconciliation. Integrating disturbance-based practices such as prescribed burning for ecological purposes within Closer-to-Nature forest management could help restore structural complexity, sustain fire-dependent biodiversity, and enhance forest ecosystem resilience under changing climate conditions.