Trees are one of our planet’s primary producers of oxygen, a gas necessary for all life! Before deciding you need more O2 in your life, you might wonder which trees produce the most oxygen. How do they do it?
Maple, beech, true fir, spruce, and Douglas-fir trees produce the most oxygen. They do this using photosynthesis, which converts carbon dioxide into oxygen. Trees help our environment by reducing the effects of climate change, detoxifying poisonous gasses, and balancing atmospheric temperatures.
Read on to discover more about which trees produce the most oxygen as well as how the process of photosynthesis benefits you and all life on our planet.
What Trees Produce The Most Oxygen?
There are different approaches to determining a tree’s oxygen production, and they often yield different results. Despite this, research has consistently shown that oxygen emission is proportional to a tree’s leaf mass. Technically, this is known as the Leaf Area Index (LAI).
LAI refers to the total leafage in a tree’s canopy, which is the upper part of the tree, including its branches, leaves, or needles. An article in the Journal of Experimental Botany tells us LAI is the total area of one side of leaf tissue per unit, which can also measure tree growth rate.
Based on its LAI, a tree has a certain output of O2.
Below are the trees that produce the least to the most amount of oxygen:
- Least O2: pines, which are coniferous (cone-bearing) and evergreen (stay green all year).
- Average O2: oaks and aspens, which are primarily deciduous (shed leaves).
- Most O2: maples, beeches, true firs, spruces, and Douglas-firs. These trees are a mixture of deciduous, coniferous, and evergreen.
Since it is beneficial for you to have trees in your yard that produce the most oxygen, let’s take a deeper look at the top five oxygen-producing trees.
Maple trees belong to the genus Acer, which is in the family Sapindaceae. There are around 125 maple species throughout the world. Although there are 12 species native to North America, these are the five species most often seen: sugar maple, red maple, silver maple, boxelder, and bigleaf.
Like fingers from a hand, a maple tree’s leaves emanate outwards from the leafstalk. Many people admire a maple’s leaves during autumn, which is when, for many species, they turn vibrant colors. A maple tree is deciduous, so their colorful leaves will eventually drop, and the tree will become dormant during winter.
Regarding oxygen production, a mature silver maple tree, for instance, can emit enough O2 in one day for two people. On the same day, a silver maple can consume nearly 100 gallons of water from the soil and disperse it into the atmosphere. Within a year, a silver maple can take in about 48 pounds of carbon dioxide.
Although they are very beautiful and create heaps of oxygen, some maple trees are messier than others. To learn more about these trees, check out 4 Maple Trees That Produce The Most Helicopter Seeds.
Beech trees belong to the genus Fagus, which is in the family Fagaceae. There are between 10 and 13 beech species throughout the Northern Hemisphere. The most commonly known species are the American Beech, which is native to eastern North America, and the European Beech, which is native to Eurasia.
A beech tree’s leaves are oval-shaped with parallel veins and toothed edges. A beech’s leaves turn vibrant shades of yellow during autumn. Just like a maple tree, a beech tree is deciduous; so, their colorful leaves will eventually drop, and the tree will become dormant during winter.
In one hour, a beech tree can take in 5.5 pounds of carbon dioxide. During the same hour, a beech tree can release 3.75 pounds of oxygen. This is enough to supply 10 people per year with oxygen.
True Fir Trees
True firs belong to the genus Abies, which is in the family Pinaceae. There are more than 40 species of true firs, all of which are evergreen trees. They are native to Asia, Europe, northern Africa, and North and Central America.
A true fir’s leaves are like needles (characteristic of a coniferous tree) and directly grow from its branches. A unique feature of a true fir is its needles’ bases look like suction cups, which attach to the branches. When these needles detach from the branches, they leave behind noticeable circular indentations.
Several true fir species are raised on Christmas tree farms and later harvested for temporary display inside homes. One acre of Christmas trees can give off the amount of oxygen needed for 18 people. This same acre of Christmas trees will take in around 500 pounds of carbon dioxide annually.
Spruce trees belong to the genus Picea, which is in the family Pinaceae. There are around 40 species of spruce, all of which are evergreen trees. They are native to typically colder regions in the Northern Hemisphere.
These trees may require a bit of extra care to reach their full potential. Take a look at this great piece about how to properly fertilize spruce trees, 5 Best Spruce Tree Fertilizers (And How to Use Them).
A spruce tree’s leaves are like needles (characteristic of a coniferous tree) and are attached to woody pegs that project from the branches. When these needles detach from the branches, the woody pegs remain, which is why a spruce tree’s branches can feel rough if touched.
In terms of oxygen production, a mature short-needled Norway spruce, for instance, can emit 58% more O2 than a beech tree. In fact, a Norway spruce can photosynthesize for 260 days per year while a beech can only photosynthesize for 176 days per year. We will discuss photosynthesis, an integral part of a tree’s oxygen production, in the next section.
Douglas-firs belong to the genus Pseudotsuga, which is in the family Pinaceae. There are about six species of Douglas-firs, all of which are evergreen trees. They are native to eastern Asia and western North America.
A Douglas-fir tree’s leaves are like needles (characteristic of a coniferous tree) and directly grow from its branches. Each needle is borne alone and has a little stalk at its base. Interestingly enough, Douglas-firs are not true firs: they were named after David Douglas, a botanist who first recorded the tree for Western science.
Since a Douglas-fir is an evergreen, it can photosynthesize and emit O2 throughout the year. A Douglas-fir’s needles are coated in a protective layer that stops an extensive loss of water. This allows the tree to produce oxygen during winter with limited sunlight.
How Do Trees Produce Oxygen?
As previously mentioned, photosynthesis is an integral process for oxygen production. In this process, trees obtain three resources to create their food—sunlight, carbon dioxide, and water.
They absorb sunlight (and turn it into glucose, a sugar), and they take in carbon dioxide from the air through tiny holes on their leaves. Trees also lap up water from the ground with their roots.
After trees consume those three resources, they create the food to help them grow.
According to research from the Canadian Journal of Botany, this food nourishes all parts of the tree and gets distributed this way:
- 60% to the tree trunk.
- 20% to the roots.
- 15% to the stems
- 5% to the leaves.
The tree releases any remnants from making this food through their leaves as oxygen. Typically, one mature tree can produce enough oxygen for up to four people. The process of photosynthesis is precisely the reason that Earth has a livable atmosphere for all animals, including humans.
Few people know trees respirate along with photosynthesizing. They use sugars they have already made through photosynthesis. When they break down these sugars, the trees emit energy.
It requires trees to consume oxygen and discharge carbon dioxide. This process is the exact opposite of photosynthesis, and it occurs in both the leaves and stems of trees.
If you would like to read more about photosynthesis, By the Light of the Sun: Trees, Wood, Photosynthesis and Climate Change is a fantastic read. It details how photosynthesis occurs and ways we can use it to counteract climate change.
A Tree’s Leaves Are Necessary For Photosynthesis
Leaves are critical in the process of photosynthesis. They take in the carbon dioxide gas from the atmosphere. The gas enters a tree through the tiny holes on their leaves called stomata.
The place where photosynthesis happens is in the leaves’ chloroplasts, which are the green sections of the leaves. Leaves are green because of chloroplasts. Deciduous trees whose leaves lose their green coloration in the autumn and winter can no longer photosynthesize.
Trees like maples, oaks, aspens, cherries and chestnuts are deciduous trees. As soon as they drop their leaves, they cannot pull in carbon dioxide nor produce oxygen. These trees will overcompensate for this loss of oxygen production during the spring and summer.
Some deciduous trees, however, have green stems; this includes aspens. These stems can photosynthesize if the temperatures are not too cold during winter. Instead of taking in carbon dioxide from the atmosphere, these stems make their own and use that for photosynthesis.
Trees that have green stems can use their self-made carbon dioxide to photosynthesize after their leaves have dropped. However, trees never photosynthesize as much during winter as they do during summer. Most of the oxygen on our planet is created by trees during spring and summer. Deciduous trees are mostly dormant during winter, and evergreen trees photosynthesize at much a slower rate in that season.
Even if it is winter in one hemisphere, this only means it is summer in the other hemisphere. Wherever it is spring or summer on the planet, trees are still busy creating oxygen. Leafless trees in one place mean there are new leaves somewhere else.
Traits And Conditions That Make Trees Produce More O2
It is challenging to measure exactly how much oxygen any particular tree produces. Even so, there are several traits of trees and conditions that are shown to contribute to higher oxygen production.
A tree with more leaves will release more oxygen. This is because the tree has a greater advantage in photosynthesizing: more leaves are undergoing the process and creating oxygen as a natural byproduct. In addition, a tree with an expansive canopy will often absorb more sunlight and potentially photosynthesize at a quicker pace.
An actively growing tree will emit more oxygen than one that is near the end of maturity, is elderly or dying. An actively growing tree demands more glucose to reach maturity; thus, this tree is rapidly photosynthesizing and transforming carbon dioxide, water and sunlight into food. This inevitably produces more oxygen.
Temperature affects the rate of photosynthesis. Usually, higher temperatures expedite the photosynthesis process for trees. Conversely, lower temperatures (between 32 and 50 degrees Fahrenheit) slow the photosynthetic speed. This is because the enzymes that facilitate photosynthesis do not work as efficiently, which reduces glucose creation. It can even stall the growth of the tree.
High rates of oxygen production can feasibly come from both deciduous and evergreen trees. One does not dominate the other. On one hand, deciduous trees often have leafier canopies than evergreen trees, which can allow for more sunlight absorption, but they also drop their leaves annually, which takes out oxygen from the air.
Evergreen trees that grow in colder climates can have a slower photosynthetic process in the coldest months. Despite being green all year, they will not contribute much oxygen to the atmosphere during winter. On the flip side, since they do not drop their leaves, they can still, under the right conditions, photosynthesize all-year long.
Based on the top oxygen-producing trees discussed earlier, it’s fascinating to note two of them, maple and beech, are deciduous. The three others, true fir, spruce, and Douglas-fir, are evergreen. Again, neither one of these types of tree absolutely surpasses the other in oxygen production.
Genetically engineered trees show promise of emitting high levels of O2. Some of these trees have been recorded to grow at 35 feet each year, which means they are rapidly photosynthesizing. Investing more in these trees might have a significant effect on our atmosphere.
How Do Trees Help The Environment?
The world currently has over 3.1 trillion trees, according to Nature. While this is a stunning number, it’s below half the total number of trees that were on the planet prior to human impact. Given that carbon dioxide has substantially increased during the last 50 years, it’s more important than ever to protect the tree population.
Trees are truly a treasure. Along with their natural allure, they provide a heap of necessities that improve the health of Earth. They enhance air quality, balance climate temperatures, raise the quality of soil, and offer food, shade, and shelter for people around the world.
Trees Reduce Harmful Effects Of Climate Change
Of the air that we breathe, oxygen is one-fifth of it. Annually, one acre of trees can produce enough air for 18 people. Trees and other photosynthesizing plants are imperative for all animal lives, including human lives, on Earth. Otherwise, we would eventually be unable to breathe.
As trees emit life-giving O2, they also take in carbon dioxide; clearly, trees have a deep impact on our environment. Carbon dioxide is the primary cause of the greenhouse effect, which holds heat in our planet’s atmosphere. This makes Earth warmer and, ideally, a more tolerable place to live.
Trees hold carbon dioxide in their trunk fibers. This, in turn, purifies the air around them and minimizes the harmful effects of CO2. This enhancement of air quality is especially beneficial in cities that have more pollutants than other areas.
In one year, a mature tree will take in over 48 pounds of carbon dioxide and convert it into oxygen. When there is too much heat (which is an overabundance of greenhouse gasses, such as carbon dioxide), this causes climate change. Climate change is why glaciers melt at unprecedented rates and why hurricanes devastate more lives each year.
Trees Detoxify The Environment
Even one acre of trees plays an essential part in preventing unprecedented climate change. One acre of trees takes in the same amount of CO2 that a vehicle creates after driving 26,000 miles. This same acre of trees also takes in the amount of carbon dioxide that two vehicles create within a year.
Trees do more than only absorb unsafe levels of carbon dioxide. Their leaves store other harmful gasses such as sulfur, ammonia, and nitrogen oxides. They are an all-natural detoxifier for the environment.
Trees also help conserve energy by minimizing air conditioning needs by nearly 50%. This not only saves us money on our utility payments but also minimizes the production of poisonous gasses. Trees are equipped to protect our world.
Trees Balance Atmospheric Temperatures
The leaves of trees create a cooling result in the atmosphere. The tiny holes in leaves, stomata, emit water vapor into the air. This is a process called transpiration.
Transpiration helps balance moisture levels in the atmosphere as well as temperatures. Trees planted near streets and buildings, for instance, are beneficial because they will decrease the surrounding temperature. In addition, the natural shade from trees also cools any creature who requires a respite from the sun and heat.
Not only do trees reduce atmospheric temperatures, but they also purify rainwater by breaking down the water molecules with their leaves. As trees purify this rainwater, they also prevent soil erosion during heavy rainstorms with their canopies and root systems. This reduces the risk of mudslides and flooding.
If you’d like to learn more about how trees help the environment, check out our article: 7 Amazing Ways Oak Trees Help The Environment.
It’s Time To Plant Some Trees!
Besides benefiting the community at large, planting trees in your yard can greatly improve your quality of life. Consider planting maple, beech, true fir, spruce, or Douglas-fir trees. They produce the most oxygen out of any tree species. Photosynthesis allows this oxygen production to happen.
With the many ways trees add to your health and that of the planet, it is time to plant some of this deciduous and evergreen vegetation in your yard today.
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