Consider a 1,000 year old forest and a 30 year old tree farm. How do the differences between these resources affect how renewable the resources are?

Presumably the 1000-year old forest contains very slow growing and large trees. The 30-year old tree farm in contrast likely contains fast-growing trees such as pine. The ancient forest is much less renewable compared to the tree farm as the forest requires such a long time to establish. Therefore, the ancient forest should be protected from exploitation. The tree farm in contrast can be exploited under appropriate forestry management, where the growth of saplings is staggered over multiple years, so that at every year within a 30 year life cycle, a portion of the trees are ready to be harvested.