Promote structural diversity: Diversify tree age classes

Adaptation Strategies and Actions

Promote structural diversity: Diversify tree age classes

Adaptation type:

Land and forest stewardship or restoration

Strategy:

Promote structural diversity

Action

Promote diverse tree age classes
Climate change is predicted to increase the frequency and intensity of storm events. Pests are also predicted to increase. These disturbances often have a disproportionate impact on certain ages of trees. For example, a wind storm is likely to do more damage to an old, large tree than a sapling. Certain pests may prefer young trees. Diversify the tree ages in order to increase resiliency. If one of these disturbances impacts your woods, there will likely be trees of different ages there to take its place.

Diverse age classes. Photo credit: Anthony W. D'Amato

To diversify tree ages, create gaps in the canopy to let sunlight reach the forest floor. The canopy gap size will depend on which species you are trying to regenerate. For example, sun-loving early successional species will need large gaps (>1/2 acre), while shade-tolerant late successional species, such as maples and balsam fir, need only the gap created by felling a single mature canopy tree. Diversifying tree ages will also provide a diversity of habitat conditions; some wildlife species prefer young, seedling forest while others prefer mature forest with many canopy layers and many prefer a little of both. In addition, promoting diverse age classes can also increase the forest's ability to store carbon by increasing the total number of trees growing in the forest. Carbon storage refers to the amount of carbon contained in tree biomass^? in a forest. In fact, about 50% of a tree’s mass is carbon.