It's to the best of our knowledge from PRX.

Trees are terrific.

They're the Earth's lungs.

They suck carbon out of the atmosphere and pump oxygen back in.

They're also the oldest living creatures on the planet.

There's a celebrated tree in Norway that's been dying and resurrecting for over 9,000 years.

Well, you're saying there's one tree that's been living for 9,000 years?

The root mass has been.

The root mass is on the order of 100,000 years old.

I'm Anne Strange Champs, and if trees are that old, could they also be wise?

You can think of this, like a huge brain growing out through the forest from this single tree.

Yeah, because it sounds like neural networks, right?

Yeah, basically they're like neural networks.

We've actually found that the patterning of the network is just the same as a neural network.

This hour, The secret life of trees.

It's to the best of our knowledge. I'm Anne Strangeamps.

When was the last time you really looked at, really thought about a tree?

There's this beautiful oak tree that I've admired for 19 years.

I'd looked at it with fond appreciation, but I never once stopped and took a picture of it.

Photojournalist Mark Hirsch.

So I parked by truck.

We're in my street shoes.

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