4 HN users recommended this explainer4 months2013–2026score 5.5
Years with an HN recommendation, 2007–2026
HN commenters recommend it as one of Veritasium's best videos and one that has aged well.
Veritasium explains how trees lift water from roots to the top of tall trunks, using transpiration pull and the negative pressure that liquid water can sustain. It explains why trees do not need pumps or valves.
“I recommend watching, I think it's one of the best veritasium Dereck has ever produced.” (HN, 2026)
> all it should take is a system of valves, That would work, but it's not how to works apparently. According to this veritasium video, it's because of "negative pressure" aka tension. [this video] I recommend watching, I think it's one of the best veritasium Dereck has ever produced.
Explains tree water transport via negative pressure, not valves.
This is an interesting video with an alternate explanation - the pressure required to get water to the top of the tree. Normally you can only suck a water column up 10 meters, and that's using a perfect vacuum - but trees can grow higher than that. The secret sauce is that in a liquid rather than a gas, you can have a negative pressure. [this video]
Explains how trees pull water up with negative pressure.
... May we have the solution to the questions, also? I went through the concours too but I am very rusty. See also Veritasium on that topic: [this video]
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