From stands to microsites: factors influencing the initial restoration success of an endangered conifer after fire

Abstract Introduction Post‐fire planting in severely burned forests is emerging as a crucial restoration necessity. Severe wildfires alter biological legacies and microsite conditions, consequently affecting the efficacy of standard reforestation efforts. Therefore, it is critical to understand the microsite factors driving initial seedling establishment under varying conditions. This is especially urgent for the endangered conifer Araucaria araucana in southern South America, which shows low resilience to high‐severity fires. Objectives We evaluated how stand‐scale (measured in plots of 700 m 2 ) factors (e.g. burn severity and topography) and microsite scale (i.e. distance to fallen logs) influence the initial establishment of A. araucana seedlings and the microclimate (e.g. daily maximum temperature). Methods We planted 285 nursery‐raised A. araucana seedlings near (0.1 m) and far (2 m) from fallen logs in unburned stands and in stands affected by low‐ and high‐severity fires. Over two growing seasons, we monitored seedling survival, height growth, and dead foliage, and used data loggers to record air temperature, relative humidity, and soil moisture. Results After two growing seasons, average seedling survival was 50% in unburned and low‐severity burned stands, and 25% in high‐severity stands. High‐severity stands with topographic exposure reduced seedling survival and height growth and increased the proportion of dead foliage; however, proximity to fallen log microsites significantly mitigated these effects and reduced daily maximum temperature. Conclusions High‐severity stands represent the most adverse post‐fire conditions for seedling establishment and are typically where natural regeneration fails. Strategically planting in favorable microsites can substantially improve restoration outcomes.