Pine cones: Keeping seeds from roasting
During a forest fire, pine seeds have better chances to survive while they are still inside the cone. But, What are the limits of this protection? Does this protection differs depending on the temperature and time of residence of a fire?
Forest fire conditions were simulated by heating cones inside an oven using three temperatures and three times of exposure. Certain combinations of these factors represent the conditions of canopy, surface or soil scenarios. Cone opening was measured in response to these treatments.
In general, there is an increase in cone opening along with temperature and time, but the effect of temperature and time is more variable at certain combinations (200ºC and 1001C with 20min). Also, at low temperatures (100ºC), time had a weaker effect on opening.