by Eva Dreyer
Why are we inclined to remove dead trees in the first place?
As most of us already know, we have a very fractured and exploitative view of nature. We like to profit from what we can and clean up what we cannot. Our “clean up” attitude leads to weeding, trimming, pruning, mowing, fencing, replacing important habitats such as thorny scrub with more “favourable” ones that please the eye, and the list goes on. We are very aesthetically inclined, and we project these views on nature, seeking out perfectly shaped and shined fruits and manicured parks. So, it is plain and simple to understand that we have a very hostile relationship with nature’s “uglier” sights; those involving death and decay. This article’s point of discussion is on why we need to change our attitude toward dead and dying trees, and how this acceptance of death can bring more life.
This topic is near and dear to Trinity staff and students’ hearts after the falling and felling of the campus’s iconic Oregon maples in 2018. These trees were in poor health from stress and fungal disease, and experts made the tough decision to remove the Library Square maples after the tragic collapse of the huge Front Square tree due to the risk of safety hazards and damage to buildings. This was also an example of “salvage logging”, the practice of removing trees that have been damaged by disease, insect infestation, wildfires, and other natural disturbances for the purpose of preserving the economic value of the tree that would otherwise be lost if left to decay. Supporters of salvage logging argue that it is the more sustainable option, however there is much more to the issue than simply the economic benefits of recovering wood.
“we need to change our attitude toward dead and dying trees, and how this acceptance of death can bring more life”
Why should dying trees be left to die?
While the death of a tree marks the end of one life, it brings benefit to thousands more. At least 80 species of bird and 100 animal species rely on dead or dying trees for the resources they provide. Birds use snags, limbs, and logs from dead trees for perching, foraging, and nesting. There are also countless wood-decaying insects and fungi whose entire life cycles take place on or within dead or dying trees. Therefore, allowing dead trees to decay in their ecosystems is a huge opportunity for increased biodiversity. A collapsed tree also serves as groundcover to lessen soil erosion and protect young seedlings from overgrazing. The breakdown of organic matter from dead and decaying trees also allows for natural nutrient recycling within ecosystems, increasing soil health. Regrowth that occurs after human disturbance is dramatically different to that which occurs after natural disturbance of a fallen tree, meaning a single dead tree being left alone can change the trajectory of succession for its entire surroundings. Salvage logging allows for open areas to be colonised by light-demanding, highly competitive species, sometimes completely inhibiting vegetative succession to progress to late successional trees. In fact, studies on the ancient Białowieża Forest in Poland, one of the closest to pristine old growth forests in European Lowland, found that salvage logging actually had greater negative effects on forest regeneration than that of insect pest outbreaks themselves.
When and where should dying trees be left alone?
Unfortunately, letting dead trees lie is not a one-size-fits-all solution. As seen with Trinity’s Oregon maples, there are times when we must intervene and remove unhealthy trees for the sake of safety and to prevent potential damages. Dying trees should not be left alone in busy public spaces or urban areas as there is a risk associated with the potential for trees to fall and injure people, cause damage to nearby buildings or block roads. They should also not be left alone if they are carriers of highly threatening diseases that could spread to other trees. However, there are special exceptional cases here. For example, live trees infected with Ash dieback disease should not be felled to avoid further spore dispersal and to attempt to keep as many disease-resistant trees as possible. These trees should only be felled if they are a damage or safety concern.
Leaving trees to decay should be prioritised in rural areas, on farmland, parkland, or public land where it is safe and possible, in our personal home gardens and so on in order to increase biodiversity and improve ecosystem health. The size and species of the tree in question should be taken into account – for example, deciduous and hardwood trees produce far more cavities than evergreens or conifers. It is therefore ideal that there is a diversity of trees left to decay in one environment for the best biodiversity opportunities.
“If we want a healthy planet, we need to get used to the “ugly” sights of nature. Perhaps our distaste for the sight of a rotting tree comes from our own fear of ageing and death”
Full circle moments
While it is straightforward to list all of the ecological benefits of allowing dead trees to decay, the most important takeaway is that we must change our perspective. If we want a healthy planet, we need to get used to the “ugly” sights of nature. Perhaps our distaste for the sight of a rotting tree comes from our own fear of ageing and death; Western culture harbours a hatred for ageing, one of the most innately natural aspects of life. Maybe we can collectively learn a lesson from the full circle nature of life, and all of the beautiful benefits that decaying trees can bring to their ecosystems.