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How long can trees live?

Dear Dr. Universe: How long can trees live? -Jessy, 8, Seattle, WA

What kinds of trees are in your backyard? Do they have pinecones? Colorful leaves? Pods with seeds? Tell us more or send a picture to Dr.Universe@wsu.edu.

Dear Jessy,

As I was hiking through the bristlecone pine forests of the Sierra Nevada recently, I stumbled upon a tree barely six inches tall.

It was growing—slowly, but surely. I was surprised to find this tiny pine tree was already about 40 years old.

Some trees will stop growing once they reach that age. But others live much longer. In fact bristlecone pine trees aren’t just the oldest trees, they are some of the oldest living things on our planet. They can live for about 5,000 years.

“These trees were growing when the Egyptians were building the pyramids,” said my friend Kevin Zobrist, a forester at Washington State University.

Zobrist knows a lot about different trees and told me a bit about bristlecone pine trees.

By the time the pines are about 5,000 years old, they will stand 60 feet tall with a trunk that is nearly five feet around. If we were to cut into the trunk, we could look at its growth rings. Each ring would signify a year of its life. We would have a lot of counting to do.

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Click to zoom in.

On my hike, I noticed some of the trees’ young pinecones were purplish-pink. Eventually they would turn brown and fall to the ground. I spotted a few old cones by the tree. They had that fresh pine scent.

I looked up at the branches that twisted and stretched like arms up to the sky. I wondered how on earth these trees were able to live such long lives.

Zobrist explained that bristlecone pine trees are tough and have adapted to their environment. They are equipped to deal with drought, extreme climates, and insects that might cause serious damage if they attack.

For example, the tree can actually shut down or go dormant for a while, if conditions are too harsh. This helps the tree survive for thousands of years.

“They teach us that nature is resilient,” Zobrist said. “They teach us that nature can carry on.”

Of course, not all trees live quite as long as these pines. But many live longer than humans and us cats.

The redwood trees of California are about six times taller than the bristlecone pines. Some of them have been around for nearly 2,000 years.

Even when a tree dies, it finds a new life. Creatures and plants on the forest floor are counting on the trees to get old, die, and fall. They can use the fallen trees as their home or for food.

It’s been said that trees are our planet’s lungs. They help make the oxygen we breathe and keep life thriving on our planet. I took a deep breath of the mountain air and said a quick thank you to the trees before heading down the trail, on to the next adventure.

Sincerely,

Dr. Universe

How do cats land on their feet?

Hi Dr. Universe! I’m Bree and I just wanted to ask, how do cats land on their feet? -Bree, 10, Williamsburg, VA 

Dear Bree,

Curiosity can lead us cats to some pretty great heights. We like to climb trees and sneak along tall bookshelves. Sometimes we might have a bumpy landing, but more often our amazing cat reflexes help us land on our feet. » More …

Why do we get scared?

Dear Dr. Universe: Why do we find some things scary? -Jack H., 8, UK 

Dear Jack,

While our fears might be different, we all get scared sometimes. Vacuums, dogs, and even cucumbers make my hair stand on end. Perhaps for you it’s spiders, the dark, or the thought of monsters under your bed.

My friend Michael Delahoyde is really curious about what freaks us out. As an English professor at Washington State University, he’s even taught a course about monsters. » More …

How do spiders make silk? And 5 other great STEM questions to explore in October

How do spiders make silk? And other questions to explore in October

How do spiders make silk?

Spiders can do some amazing things with their sticky, stretchy, and super-strong silk. Us cats are pretty curious about these little silk-spinning machines, too. Besides chasing spiders around, I’ve watched them use silk to build webs, catch bugs, and protect their young spiderlings.Screen Shot 2016-04-04 at 9.05.13 AM

Read more

Do bats have habits?

You are onto something. Quick, to the bat-lab! That’s where I met up with my friend Christine Portfors, a scientist at Washington State University who studies fruit bats.

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Why do leaves change colors?

Ever since I was a kitten, I’ve loved picking up big maple leaves in the fall. I’d take them home, put them under a piece of paper, and rub the side of a crayon over the top. It makes a great print of the leaf.

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Do spiders have good eyesight?

Most spiders have quite a few eyes, but they usually can’t see very well. Then again, seeing isn’t everything. That’s what I found out when I went to visit my friend Rich Zack, a scientist at Washington State University who knows a lot about insects and spiders.

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Screen-Shot-2016-07-07-at-9.05.40-AMWhy are apples red?

Just the other day I was biting into a crunchy, delicious red apple when I was reminded of your question. I started wondering why apples are red, too. I called up my friend and apple expert Kate Evans, a scientist here at Washington State University. Her research helps us develop new kinds of apples.

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Can we engineer new bones?

A couple months before you were born, your skeleton was soft and bendy. It was made out of cartilage, the same material that’s in your nose and ears now. But when certain cells in your body called osteoblasts and osteoclasts began to work together, new bone started to form.

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Why does the Earth spin?

Dear Dr. Universe: Why does the Earth spin? -Morven, 8, Dundee, Scotland; Judith, 9, Sabah Malaysia; Mara, 11, USA

Dear Morven, Judith, and Mara:

No matter how still we stand, or if we’re in Scotland, Malaysia, or the United States, we are always spinning. Our Earth spins at a constant, very fast speed as we make a trip around the sun. » More …

How do spiders make silk?

Dear Dr. Universe: How do spiders make silk? Also, sometimes spiders hang down from the ceiling, when they climb back up, where does the silk go? –Johnny, 8, Pullman, WA

Dear Johnny,

Spiders can do some amazing things with their sticky, stretchy, and super-strong silk. Us cats are pretty curious about these little silk-spinning machines, too. » More …

Why can birds fly, but we can’t?

Dr. Universe: How can birds fly when they flap their wings, but when we flap our arms nothing happens?  – Ravin, 9, London, UK

Dear Ravin,

Screen Shot 2016-07-07 at 9.05.40 AMNo matter how much you flap your arms or I flap my paws, gravity keeps us pulled to Earth. But when birds use their strong muscles to start flapping their wings, something amazing happens. » More …