Why Does Tree Planting Have a Pollution Problem?

Planting trees has been hailed as one of the most cost-effective and efficient ways of removing carbon from the atmosphere and combating the onset of climate change. In the UK, Scotland has been particularly proactive in planting new trees, having set itself the target of repopulating 10,000 hectares (or 24,710 acres) each year across the nation.

However, it appears that the endeavour is not completely beneficial to the environment. In order to protect young saplings from the eager appetites of deer, rabbit and other wild animals, hundreds of thousands of plastic tree guards are put in place to increase the trees’ chances of reaching maturity. Unfortunately, these guards are often forgotten about after the fact and left to rot, creating pockets of plastic pollution throughout the Scottish countryside.

A necessary evil?

Tree guards, which were invented in Scotland, are required to ensure that the new vegetation is allowed to gain a foothold free from molestation by other forms of wildlife, depending upon the environment and the specific species of tree being planted. Unfortunately, the common practice among the public sector is to use single-use plastics for the job, meaning that once their role has been fulfilled and their five- to eight-year lifespan expired, they’re simply left behind as waste.

On land, plastic can take up to 1,000 years to decompose. In that time, it can inhibit the growth of vegetation, trap animals or even be mistaken for food and be ingested by them, which plays havoc with their internal digestive tracts. Over time, the substance may break down into microplastics - which are potentially even more dangerous a substance, since they can accumulate in the food chain and even affect humans.

However, Forestry and Land Scotland are adamant that this is not a large-scale problem – or one without a solution. A spokesman for the organisation pointed out that a mere 1.6% of the 25 million new trees planted each year (approximately 400,000) require the use of the guards. The body are also enthusiastic about using more environmentally friendly alternatives to single-use plastics.

Changing for the future

Plastic pollution is a major issue on both sea and land and the scientific community has long been searching for a solution to the problem. One such avenue of research is the unlikely union of forensic science and artificial intelligence, as machine learning is being use to predict where plastic pollution may be at its most pronounced and damaging. However, as with all things, prevention is infinitely preferable to the cure.

With that in mind, one charity based in Findhorn, Moray aims to dispense with the use of plastic tree guards altogether. Trees for Life is responsible for planting over 1.6 million trees each year, but prefers to employ fencing made from wood or other natural substances to keep hungry animals at bay. Similarly eco-friendly solutions are being pursued elsewhere, while effective clean-up schemes are being pursued for those locations where plastic tree guards must be used.

“Ideally, if a viable alternative was to become available, we'd like to stop using tree guards altogether,” say Forestry and Land Scotland. “However, until such time as a suitable product becomes available, we will continue to look at minimising the use of tree guards, maintaining them in situ, removing them when trees are established and then disposing of them appropriately.”