How Much Do You Know About Trees?


By: Annette

5 Min Quiz

Image: Shutterstock

About This Quiz

Even if you grew up in the densest of cities, you probably knew where you could go to be among trees. Trees are essential for human health. They cool the temperatures around them, they help manage moisture and secure topsoil, and they absorb carbon dioxide and release oxygen. Indeed, if humanity goes over our "carbon budget" by burning too many planet-warming fossil fuels - a genuine danger within as few as 20 years - trees are the thing that will save us, with their ability to sequester carbon directly from the air. 

Ironically, trees also provided those very fossil fuels in the first place - the vast majority of coal on the planet is made up of fallen wood that couldn't rot as the relevant microbes hadn't evolved yet, meaning stacks of fallen wood from dead trees eventually crushed itself down into coal. That means trees of the distant past have warmed and lit our homes, even as their current relatives save us from the consequences.

More than saving our planet in the near future, though, trees save our sanity now. Studies have shown that spending just five to ten minutes a day in a wooded area can help alleviate symptoms of depression and anxiety. Trees: they're just that good. But despite the fact that trees give us mental health, physical comfort and a planet fit for human habitation, many of us don't know a lot about them. Most people can't tell their hardwoods from their softwoods, their birches from their beeches, their conifers from their broad-leaved deciduous trees. 

Fortunately, this quiz is your opportunity to show us what you do know, and perhaps fill in a few gaps along the way!

Trees are the _____ living organisms on Earth.

Trees are the longest living organisms on Earth. Not only that, but they also never die of old age.


Pine trees spread seeds in the form of _____.

Pine trees spread seeds in the form of cones. Their cones actually have separate genders.


"Knock on wood" came from a time when people used to knock on ______.

The phrase "knock on wood" actually comes from a time when Pagans used to knock on trees. They did this to summon protective spirits that resided within the trees.


How much carbon dioxide can a mature tree absorb each year?

A mature tree can absorb as much as 48 pounds of carbon dioxide each year. By the time it's 40, a tree can have taken in as much as 1 ton of carbon dioxide.


Moss grows on the side of the tree trunk that has more ______.

Moss grows on the side of the tree trunk that has more shade. In northern temperate climates, moss will grow on the northern side of the trunk. That means that if you get lost in the woods, you can find your way.


Pine trees grow on ______ continents.

Pine trees grow on 6 out of 7 continents. The only continent where they do not grow is Antartica.


Trees _____ air temperature.

Trees naturally lower air temperature by evaporating water in their leaves. Talk about a natural defense against global warming!


The different parts of the tree grow ______.

The different parts of the tree grow at different times. For instance, the foliage grows in the spring, and the trunk grows in the summer.


How much water does a tree drink each day?

A large tree can drink as much as 100 gallons of water per day. While it does this, it actually cleans the water.


Strategically planting trees can _____ your energy bill.

Strategically planting trees can improve your energy bill by as much as 25%. They can provide shade during the summer, and also insulation and windbreak.


Trees are able to ______ with one another.

Trees are actually able to communicate with one another. When one tree is being attacked by insects, it can signal danger to the other trees so that they can start their own defense.


One large tree can provide a ______ supply of oxygen for four people.

One large tree can provide a day's supply of oxygen for four people. Shouldn't we all thank a tree today?


How much of the world's oxygen is supplied by the Amazon Rainforest?

More than 20% of the world's oxygen is supplied by the Amazon Rainforest. Better protect that beauty.


New York City has some of the highest quality water in the world thanks to _______.

New York City is a great example of how a forested watershed can provide some of the highest quality drinking water. In 1997, the city spent $1.5 billion to preserve their forested watershed in upstate New York.


Office workers with a view of trees report ______.

Office workers with a view of trees report less stress and more satisfaction. Do we need to drive this point home any further?


Trees can cool a city by up to _____ F.

Trees can cool a city by up to 10°F. This is because they not only provide shade, but also release water vapor into the air.


A study in Baltimore showed that a 10% increase in tree canopy led to a _____ reduction in crime.

In Baltimore they found that a 10% increase in tree canopy led to a 12% reduction in crime. Outdoor spaces with trees also enjoy less graffiti and vandalism.


In New York City, every dollar spent on a tree yields _____ in return.

A 2007 study showed that every dollar spent on trees in New York City would lead to a $5.60 return. Talk about an investment that everyone can agree on.


True or False: Trees can be poisonous.

It's true that trees can be poisonous. The Manchineel tree of Florida is considered the most poisonous tress in the world.


What is Da Vinci's Rule of the Trees?

Da Vinci's Rule of the Trees states that all branches put together are equal in thickness to the trunk of the tree. This theory appears to be true in many cases.


True or False: There is a tree in the U.S. that owns itself.

It's true that there's a tree in the U.S. that owns itself. In Athens, Georgia, a professor in the 1800s deeded to a great oak tree ownership of itself and the land within 8 feet of it.


Older, bigger trees share ______ with smaller trees.

Scientists have found that older, bigger trees share nutrients with smaller trees. These smaller trees actually pay them back when they grow up.


Almost all of central Venice, Italy, is supported by ______.

The Venice Islands were literally built on the backs of trees. The foundation for the Islands is tree trunks, and they still support almost all of central Venice.


True or False: Everyone knows where the world's tallest and oldest trees are located.

It's false that everyone knows where the world's tallest and oldest trees are located. Locations are kept top secret so that tourists won't damage the trees!


There are Eucalyptus trees in Hawaii with ______ bark.

There are actually Eucalyptus trees in Hawaii that have rainbow-colored bark. No, they do not produce Skittles.


What star reduced the carbon footprint of their concerts by having trees planted?

Justin Timberlake actually had a company figure out the carbon footprint of his concerts. He paid to have trees planted to offset this carbon footprint during his nationwide tour.


Today, we have ______ trees in the U.S. than any time in 100 years.

Today we actually have more trees in the U.S. than any time in the past 100 years. Forest growth has exceeded harvest since the 1940s.


Roughly 99% of a tree is made of _______.

Roughly 99% of a tree is actually made of dead cells. Only 1% of the tree is alive at any given time.


True or False: It's possible to create artificial trees.

It's absolutely possible to create artificial trees. Columbia University did so, and their tree could soak up carbon dioxide 1,000 times more efficiently than regular trees.


Where is there an entire forest that is made up of one tree?

In Utah, there is an 80,000 year old forest that is made up of one tree. It's called a Quaking Aspen, and it has a massive underground root system.


In China, citizens over 11 are required to plant _____ trees per year.

Since 1981, Chinese citizens over the age of 11 have been require to plant three to five trees per year. That's a step in the right direction.


What percentage of redwoods have been cut down?

An unbelievable 96% of ancient redwoods have been cut down. They are some of the tallest and oldest trees on the planet.


True or False: A Bonsai Orange Tree grows miniature oranges.

It's true that a Bonsai Orange Tree grows miniature oranges. We wonder what those would taste like.


Sweden is known for its famous tree ______.

Sweden is known for its famous TreeHotel. All the rooms are literally up in the trees.


The Sandbox Tree has ______.

The Sandbox Tree is literally covered in spikes and has fruit that can explode and propel seeds. Much of the tree is even poisonous. That is one tree that you don't want to be around.


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