Plants have the capacity to store and reallocate stored nonstructural C, but little is known about the age and ecological roles of these pools. It was thought that plants allocate recently assimilated C to produce new fine roots. However, there is recent evidence that plants can allocate old stored C for the production of fine roots following a large-infrequent disturbance (LID) providing a new dimension of the fate and the implied role of stored C in plants. Here, I explore other possible adaptations of plants to allocate stored C reserves, and provide a series of open questions on the fate of old stored C in plants. Specifically, I propose that another metabolic function of old stored C may be for supporting mycorrhizal fungi colonization after a large-infrequent disturbance, because the production of hyphae may be more economical in terms of C to the plant under stressful conditions. Finally, in order to better understand plant resilience to LIDs it is critical to understand the mechanisms that regulate the fate of old stored C in plants.