What is the environmental impact of a Christmas tree, and how should you dispose of it?

“Christmas Tree O Christmas Tree, how lovely are thy branches”.

So goes the yuletide anthem, and yes, it seems humans everywhere relish the opportunity to bring a big old bit of foliage into their dwellings and cover it with twinkly trinkets to celebrate Christmas. Delightful.

But wait! Cutting down trees for a few weeks of pleasure is not very 21st century is it? We are not a pack of feckless Bolsonaros getting jacked on the illicit thrill of felling vital woodlands, are we?

Around six million trees are cut down and brought indoors each year. But should we be cutting down these trees? What impact does it have on the environment? Should we stop? Or should we keep going? And when we have had enough of Christmas and its indoor trees, how should we rid ourselves of them?

Real deal or fake fir

The first question in ascertaining whether you should be on the naughty or nice list this year is: what sort of tree have you got?

Artificial trees are bad. In fact they are not trees at all, they just seem a bit like them to our rudimentary human senses.

A single artificial tree has a total carbon footprint of around 40kg, according to the Carbon Trust. They are usually made in China, and are composed of metal and plastic, which will ultimately go to landfill. This is bad.

The Woodland Trust has no truck with these plastic imposters. Their website says: “Most are made from non-recyclable plastic and the carbon emissions generated to make them are very high. If you do opt for a fake tree, try to use it for as long as possible to reduce the environmental impact … at least a decade.” Other sites suggest it could take up to 20 years of reuse to offset the same impact from real trees.

This sounds more like a punishment than a celebration. Fake plastic trees are not the way to go, unless you already have one, in which case, you've made your bed and now you've got to lie in it, for at least ten years.

Real trees are better.

A real tree which has been cut down before Christmas and then goes into landfill has a carbon footprint of 16kg according to the Carbon Trust.

This still doesn't sound great, because it isn't. But landfill disposal is a worst-case scenario for a Christmas tree, as here it will decompose and produce methane, which is around 30 times more potent as a greenhouse gas than carbon dioxide.

However, a properly disposed of tree has a minimal environmental impact.

The Carbon Trust says: “Burning the tree, such as on a bonfire, emits the carbon dioxide that it stored up when it was growing, so there is no net increase.”

The guidance says that if you re-plant your tree, or instead have it chipped to spread on the garden, it will “significantly reduce the carbon footprint” – by up to 80 per cent.

Most councils provide a tree collection service in which the trees are chipped. This is usually the best option.

According to the Woodland Trust, “the most environmentally-friendly option is to buy a tree with roots. This means you can plant it in the garden afterwards and bring it back into the house next year.” Win-win.

Where is it from?

If you've had your tree cut down and flown in from distant lands, then there's a reason Santa's sack isn't bulging this year.

Locally grown trees are the way to go, and the Carbon Trust advises shrewd tree-buyers to find retailers selling trees which are slow grown and use no fertiliser, instead of those which are intensively grown. Forest Stewardship Council certification ensures minimal fertiliser is used.

A considerable amount of work goes into growing Christmas trees. According to B&Q, which only sells UK grown trees, the seedlings are grown for three years before they are big enough to be moved to a nursery. After a further two years of maturing, the pruning then begins in order to achieve the recognisable conical Christmas tree shape.

By the time the trees are between 6 and 10 years old, they are ready to be harvested and sold.

Other options for your old tree

As well as recycling your tree through the council, or burning it, other options for what to do with your leftover festive foliage are to:

A whopping 160,000 tonnes of Christmas trees are thrown away in the UK every year – that’s the equivalent of 12,800 London buses. According to the Soil Association “re-using your tree after the Christmas holidays is a great way to reduce waste at home.”

Ultimately, cancelling Christmas entirely would be best for the environment. This may seem obvious, but it bears repeating – preferably each and every Christmas. Birthdays are also bad for the environment but at least no trees are usually involved.