Why does Banksia ericifolia need fires at neither very short nor very long intervals?

The Banksia ericifolia, a shrub native to coastal scrublands in eastern Australia, relies on fire to trigger the release of its seeds from woody fruits. Because of its specific reproductive cycle and life span, it requires fire at appropriate intervals to persist in its environment:1

• Short intervals: If an area is burned more frequently than every five years, the population is eliminated because the plants have not yet reached the maturity required to produce their first set of seeds.1
• Long intervals: If an area is burned less frequently than every 40 years, the population is also eliminated because this duration exceeds the natural life span of the individual plants.1

Consequently, the species depends on a specific fire regime to ensure that new seedlings can establish themselves before the existing generation dies out.1