How Trees Bend the Laws of Physics

Hope this was worth the wait! So many people helped with this video: Prof John Sperry, Hank Green, Henry Reich, CGP Grey, Prof Poliakoff, my mum filmed for me in beautiful Stanley Park and Jen S helped with the fourth version of the script.

Also thanks to the Palais de la Decouverte - they helped me with the whole vacuum pump setup in Paris. No, I could not actually suck water up 10m - I did about 4m, but the vacuum pump was easily able to do it and I saw spontaneous boiling on all of our various trials. Footage from this may end up on 2Veritasium.

Trees create immense negative pressures of 10's of atmospheres by evaporating water from nanoscale pores, sucking water up 100m in a state where it should be boiling but can't because the perfect xylem tubes contain no air bubbles, just so that most of it can evaporate in the process of absorbing a couple molecules of carbon dioxide. Now I didn't mention the cohesion of water (that it sticks to itself well) but this is implicit in the description of negative pressure, strong surface tension etc.

[leokovacic]

Newton should have asked himself how an apple even got up there

[johnwielding]

I think we've just found the most intense hype man for trees

[ClamV]

This video was so good I didn’t even realize it was 8 years old

[lukenfoci]

So in short, trees do not bend the laws of physics, trees use the laws of physics cleverly...

[psykodactyle]

2012: super sucked


2019: S U P E R S U C C

[JCdiedUall]

His next video must be on how to make a 7 year old video go viral.

[mrplop]

how to bend the youtube algorithm into recommending old videos will be the next video

[bruh-uqzx]

The height limit of the trees is 256 blocks

[mBUSHattack]

This ended up being way more interesting than I expected.

[code.]

"Why should there be a height limit?"
_Minecrafters liked that_

[Mr_Soleo]

Hank saying "right?" was just praying to the gods of physics that there wasn't a pure vacuum in tree leaves.

[Drache]

Its really amazing to think that this video is almost 10 years old. I didnt even notice until after watching it
Compared to most other youtubers in 2012 this is god tier quality

[Kerbhunter_Alex]

Negative pressure?... Mind blown? naaah
*mind sucked*

[vanncio]

0:15 height limit is 256 blocks, duh.
Do your research before making such baseless accusations.

[onelazynoob]

So, here's a follow up question. Can you make a tree explode by injecting air into the xylem tube?

[Johnnysboy]

Out here in 2024 and trees sucking up water still goes hard

[thenew]

So, in short...trees are the most powerful straws on Earth.

[DraRed]

One of my favourites. I'm glad youtube threw it back at me again.

[jvajdos]

I’m a refrigeration technician, and I realized a while back that the water evaporates out of the bottoms of the leaves to refrigerate them, when water evaporates, the vapor pulls heat from the remaining source water, cooling it. This is necessary because sunlight has the potential to heat the leaves beyond the temperature they can still function for photosynthesis.

[benjaminfisk]

I love the video. What I would add is what all that extra 95% of water is doing. It keeps the tree cool by evaporating out like sweat, especially on hot days. And this means the trees regulate temperature around them by absorbing heat energy that would have baked the ground, and putting it into evaporating water molecules. And this extra water vapor that trees gradually put into the atmosphere helps make for more stable cloud formation, rainfall, and climate around them. So the magic of the trees is that a forest actually generates its own rainfall over and over. And cutting down forests removes this stable predictable rainfall. Could you do a video on the water cycle and cutting many trees leads to local climate instability.