Why we need more dead trees

By: Ella Daly, University of Alberta

The death of a tree tends to be a slow process, except, of course, when we chop them down or they’re struck by lightning. These gradual changes invite new kinds of insects, fungi, and bacteria that couldn’t previously live on the tree. As more parts of the tree die and rot, opportunities for more and more different species are created. These species include the large mushrooms you might see on rotting birch or the stringy lichens found on bare spruce trees, both of which become food for woodland animals like squirrels and caribou. As time goes on, a large cavity in the tree’s trunk may form. This can become a temporary home to animals as big as grizzly bears. Eventually, the tree will fall over. Once this happens, it can be used for food and shelter by an even greater variety of animals and plants. More diversity of species (biodiversity) helps us in many ways, such as living more sustainably and developing new disease-fighting drugs.

Despite their importance to biodiversity, we’re not very good at leaving dead trees where they fall. A large part of the global effort to take better care of our environment has been focused on forests and threats like logging. This is an issue because we harvest too many trees without replacing them – and what is a forest without its trees? In North America public awareness of logging has played an important role in conservation for decades, and continues to be relevant today. However, there are no equivalent campaigns for retaining dead stems. This is due to a lack of awareness, worries over forest fires, and the simple fact that they’re often considered an eyesore.

We need dead trees to maintain biodiversity and keep our forest ecosystems healthy and functioning, so why don’t we leaf a few behind? Globally, we need strong forest policy to retain a regionally appropriate percentage of dead and fallen trees. It sounds simple, but it’s not. In many areas, it trees can’t be left in their graves because they’re vital to local communities for firewood and other resources. In other areas, they’re removed to ‘tidy up’ the forest for aesthetics or to reduce the potential fuel for forest fires, which is an increasing public concern as communities severely impacted by forest fires like Fort McMurray (AB) and Lytton (BC) have made headlines in recent years. As with any environmental policy, the issue of leaving dead trees where they stand (or lay), is all about balance. It’s also about public perception.

Environmental policy and conservation rely heavily on public opinion to give money, time, and attention to different issues. Without public pressure, conservation happens very slowly (if at all). Researchers argue that part of the reason people have little fondness for dead trees is because they’re misunderstood. Basically, the ‘ugliness’ of dead trees makes them hard to warm up to, especially if you don’t know why they matter. They argue the only way to change forest policy, is to convince people to embrace the “life after tree death”. It’s also important to understand how the plants and animals on our own properties interact. Many landowners may be slower to chop up and remove fallen trees if they know how important they are to the biodiversity of their forest.

Our perception of the natural world can change so quickly as we learn about how all the pieces of the system work together. These changes are in turn reflected in our ecosystems through policy change and activism.

In the hope of a future Earth with biodiverse forests and in the spirit of activism, I say: long live dead trees!

Edited by B.G. Borowiec and A.E. McDonald. Header photo from Unsplash.