Environmentally conscious consumers often ask me whether a real Christmas tree or an artificial one is the more sustainable choice. As a horticulture and forestry researcher, I know this question is also a concern for the Christmas tree industry, which is wary of losing market share to artificial trees.
And they have good reason: Of the 48.5 million Christmas trees Americans purchased in 2017, 45 percent were artificial, and that share is growing. Many factors can influence this choice, but the bottom line is that both real and artificial Christmas trees have negligible environmental impacts. Which option “wins” in terms of carbon footprint depends entirely on assumptions about how long consumers would keep an artificial tree versus how far they would drive each year to purchase a real tree.
Many consumers believe real Christmas trees are harvested from wild forest stands and that this process contributes to deforestation. In fact, the vast majority of Christmas trees are grown on farms for that express purpose.
To estimate the total impact of something like a Christmas tree, researchers use a method called life cycle assessment to develop a “cradle to grave” accounting of inputs and outputs required to produce, use and dispose of it. For natural Christmas trees, this covers everything from planting seedlings to harvesting the trees and disposing of them, including equipment use, fertilizer and pesticide applications, and water consumption for irrigation.
Life cycle assessments often will also estimate a system’s carbon footprint. Fuel use is the biggest source of greenhouse gas emissions in Christmas tree production. Using 1 gallon of gas or diesel to power a tractor or delivery truck releases 20 to 22 pounds (9 to 10 kilograms) of carbon dioxide into the atmosphere.
On the positive side, Christmas trees absorb and store carbon from the atmosphere as they grow, which helps to offset emissions from operations. Carbon represents about 50 percent of the dry weight of the wood in a tree at harvest. According to recent estimates, Christmas tree-sized conifers store roughly 20 pounds of carbon dioxide in their above-ground tissue and likely store similar amounts below ground in their roots.
However, using 1 gallon of gasoline produces about the same amount of carbon dioxide, so if a family drives 10 miles each way to get their real tree, they likely have already offset the carbon sequestered by the tree. Buying a tree closer to home or at a tree lot along your daily commute can reduce or eliminate this impact.
And natural trees have other impacts. In 2009, Scientific American specifically called out the Christmas tree industry for greenwashing, because growers’ press releases touted carbon uptake from Christmas tree plantations while ignoring pesticide use and carbon dioxide emissions from plantation management, harvesting and shipping.
Artificial trees have a different set of impacts. Although many people think shipping trees from factories in China takes a lot of energy, ocean shipping is actually very efficient. The largest energy use in artificial trees is in manufacturing.
Producing the polyvinyl chloride and metals that are used to make artificial trees generates greenhouse gas emissions and other pollutants. China is working to reduce pollution from its chemical industry, but this may drive up the prices of those materials and the goods made from them.
Moreover, to consider sustainability from a broader perspective, production of real Christmas trees supports local communities and economies in the United States, whereas purchasing artificial trees principally supports manufacturers in China.
Recently the American Christmas Tree Association, which represents artificial tree manufacturers, commissioned a life cycle assessment comparing real and artificial Christmas trees. The analysis considered environmental aspects of sustainability but did not examine social or economic impacts.
The report concluded that the environmental ‘break-even’ point between a real Christmas tree and an artificial tree was 4.7 years. In other words, consumers would need to keep artificial trees for five years to offset the environmental impact of purchasing a real tree each year.
One major shortcoming of this analysis was that it ignored the contribution of tree roots – which farmers typically leave in the ground after harvest – to soil carbon storage. This omission could have a significant impact on the break-even analysis, given that increasing soil organic matter by just one percent can sequester 11,600 pounds of carbon per acre.
Consumers can’t affect how farmers grow their live trees or how manufacturers produce artificial versions, but they can control what happens after Christmas to the trees they purchase. For artificial trees, that means reusing them as many times as possible. For natural trees, it means recycling them.
This is essential to optimize the carbon footprint of a real tree. Grinding used Christmas trees and using them for mulch returns organic matter to the soil, and can contribute to building soil carbon. Many public works departments across the United States routinely collect and chip used Christmas trees after the holidays. If local tree recycling is not available, trees can be chipped and added to compost piles. They also can be placed in backyards or ponds to provide bird or fish habitat.
In contrast, if a used tree is tossed into a bonfire, all of its carbon content is immediately returned to the air as carbon dioxide. This also applies to culled trees on tree farms. And if used trees are placed in landfills, their carbon content will ultimately return to atmosphere as methane because of the way materials buried in landfills break down. Methane is a greenhouse gas 21 times more potent than carbon dioxide over a century, so this is the most environmentally harmful way to dispose of a used tree.
All kinds of factors influence choices about Christmas trees, from fresh trees’ scent to family traditions, travel plans and the desire to support farmers or buy locally. Regardless of your choice, the key to relieving environmental angst is planning to reuse or recycle your tree. Then you can focus on gifts to put under it.
Trees are not just for Christmas. They are crucial in keeping our living planet alive so we need to do our best to protect them. If you want to do more than recycling Christmas trees you can donate to Cool Earth below, a non-profit organisation working with local communities to protect rainforests.👇
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In this time of religious tensions, a small piece of good news can go a long way in restoring your faith in humanity. This positive bit, for example, comes all the way from the United States. Northeast Ohio, to be precise.
👉 In Parma, a small city close to Cleveland, a group of Muslim doctors decided to convert some of the local mosque's spare rooms into a free health clinic where everybody is welcomed, no matter if uninsured or not Muslim.
As reported by local media outlet News5 Cleveland, The Cleveland Ibn Sina Clinic opened just a few weekends ago but more than 30 patients have already received treatment.
"We have the ability, we have the potential, we have the resources,” said Dr. Mansoor Ahmed, who is one of the 20 doctors that committed to volunteering their expertise. "Giving a little bit of your time, I think, goes a long way in making a difference in people's lives," he added.
“A lot of the doctors came here from foreign countries outside the United States looking for better opportunities. Now that they are established, some of them are practicing with hospitals, some of them have their own practice, now they want to come together and give back to the community,” commented Hala Sanyurah, who is the clinic's Communication Director.
The clinic — that will not just focus on primary health issues but also on more specific diseases like asthma, diabetes, and mental illness — is the first free medical facility in the region.
Credit header image: Stu Spivack
The mere mention of the term “polar vortex” elicits thoughts of bitterly cold temperatures and dangerous wind chills. Most people are aware that the frigid air in the Northern Hemisphere is coming directly from the Arctic region, yet they don’t know why polar vortexes happen.
Not surprisingly, this has led to some rather heated debate. One side of the argument claims that the polar vortex is a result of climate change and human activity. The other side suggests this is a natural phenomenon that proves global warming is false and that humans are not involved in altering our climate.
The truth is the former is correct. But trying to convince someone to accept this reality might be a difficult challenge. Thankfully, when it comes to the cause of the polar vortex, there is a relatively easy — and for some, relatable — explanation. Quite simply, the polar vortex gets drunk.
My research expertise is in microbiology, immunology and chemical mechanisms of molecular interaction (think antibiotics).
As a science communicator, one of my greatest hurdles is defining the intricacies of research into language with which people can understand. This means going deep into the literature and finding the mechanism behind the result. It also means having a deep level of knowledge in a variety of different science branches.
In some cases, the information can be difficult to convey to a wider audience. But when it comes to the polar vortex, it’s not difficult at all.
A close examination of the chemistry associated with the onset of these cold snaps reveals a near-perfect resemblance to a chemical shift our bodies encounter during alcohol consumption. The results reveal that both humans and the planet are similarly susceptible to unexpected and unwanted movements.
Most of us can recognize when someone has had too much to drink. Their speech is slurred and they have troubles with their balance. This latter symptom is why the walk-and-turn sobriety test is effective — an inebriated person has trouble moving in a straight line.
Maintaining posture and balance is a complicated neurological process. Research has revealed that one molecule, gamma aminobutyric acid (GABA), is necessary for us to achieve this goal. Our brains use this neurotransmitter to help control the signals to our muscles, particularly when we feel the effects of gravity or being pushed by another person.
When we drink alcohol, GABA helps us preserve our balance and posture. But once we end up losing the necessary levels of GABA needed to keep us upright, we sway, stagger and stumble. Only when we’ve sobered up and increased our GABA levels are we able to regain our balance.
A similar process occurs in the Arctic.
The polar vortex, officially known as the stratospheric polar vortex (SPV), is a stable air mass that tends to stay put when it’s cold sober. In the same way we feel an internal heat during alcohol consumption, the region can warm up with an infiltration of air from the south, better known as a sudden stratospheric warming. When this happens, the steadiness of the vortex is challenged.
Much like our brains have GABA to maintain stability, the SPV also has a chemical that helps to maintain stability. It’s ozone.
When levels remain high, the vortex stays in place. But should the levels drop, then the vortex starts to sway, stagger and then stumble southward, a process known as outward eddy transport. Depending on how low the ozone levels drop, the vortex can stretch well into the southern United States and Europe. Eventually, the SPV sobers up, the ozone levels recover, and the air mass stays up north. But this recovery can be slow and leave those affected freezing for weeks instead of days.
As to what causes the ozone loss, it’s a reaction with a variety of chemicals in the air. Researchers can observe the process in real time and have found that the offenders are not alcoholic in nature but happen to be compounds that contain nitrogen and chlorine. The Earth produces these chemicals in the form of volcanic output and forest fire emissions, and this can lead to a drunk polar region.
Thanks to real-time examinations of polar vortex movements over the last 20 years, we can easily finger the culprit: industrial air pollution. These commercial activities produce more than enough of the nitrogen and chlorine chemicals to reduce ozone levels and cause those drunken staggers. The data clearly shows that the blame for the rise in those cold blasts falls squarely on us.
As this winter’s supply of polar vortex events comes to an end, so should the debate over whether the polar vortex is real — it is — and whether these movements are due to human activity — they are. Until we find ways to reduce our dependence on ozone-removing chemicals, all we can do is hope for the best and brace for the worst.
Here at Kinder, we're often busy thinking about the future of philanthropy and how charitable organizations will look like 100 years from now.
However, every now and then, it's also helpful to look back at history and realize that there's a handful of charities that have been around for so long that there's certainly something we can learn from them.
One of them is the Hospital of St. Cross and Almshouse of Noble Poverty in Winchester England, that actually prides itself to be the UK's oldest charitable institution.
Founded around the year 1132, the almshouse was initiated by Bishop Henry of Blois to support thirteen poor men who were unable to work and to feed some 100 people who showed up at the gates every day.
The thirteen men became known as the "Brothers of St. Cross". Despite the religious connotations of the term "brother", the Brothers of St. Cross were not and are not monks, therefore St. Cross is not a monastery.
The Wayfarer's Dole
The Hospital of St. Cross' most unique and famous charitable endeavor is surely the so-called "Wayfarer's dole".
According to this delightful tradition, every visitor of the almshouse can ask for a free horn of beer and a morsel of bread. As recalled by the organization's website, the custom was started by a monk from Cluny, in France, whose holy order always gave bread and wine to travelers.
After so many centuries, this tradition still continues nowadays as seen in the BBC's program Songs of Praise👇
The Hospital of St. Cross, which is hosted in a beautiful medieval building immersed in the British countryside, is regularly open for visits. Head to the organization's website for additional information.