What will happen on the site of the burnt birch forest over the next 15 years?

Since ancient times, nature has adapted to forest fires, because if the forest did not recover after the fire, we would now live in the desert. Over the years of its existence, the seeds of all plants growing around are accumulated in the soil of the forest. After a fire, a favorable period comes for the seeds, because old plants do not interfere with their growth and even more, their ash nourishes the soil with useful substances. Thus, in the first years of life, the seeds turn into young plants that grow rapidly, and after fifteen years, in the place of a burnt birch forest, a new, even denser forest will turn green.