Giant trees have no trouble pumping water to top branches

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hhhs about 5 hours ago 54 commentsRead Article on news.exeter.ac.uk

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calibas•about 3 hours ago

The largest tree on record is rejected in part because it's over the theoretical limit: https://en.wikipedia.org/wiki/Nooksack_Giant

Too bad we cut it down, along with almost every other giant Douglas-fir.

Alien1Being•about 2 hours ago

Human barbarism is not new...

"The placard recorded that the Nooksack tree produced 96,345 board feet (227.348 cubic meters) of the "finest quality" lumber.

The New York Times regarded the tree in a March 7, 1897 issue as the "most magnificent fir tree ever beheld by human eyes" and called its destruction a "truly pitiable tale" and a "crime".

The Morning Times of February 28, 1897 claimed that the wood, sawed into one-inch strips, would reach from "Whatcom [the tree's location] to China"."

fsckboy•about 2 hours ago

>Human barbarism is not new...

to be fair, without humans there would be nobody to declare "barbarism". At one time, all humans were barbarians, it took a certain level of cultural development before the word "barbarism" was necessary, so at that point it was "new". It remains be be shown whether cultures that call other cultures "barbaric" are actually "better".

mattgrice•about 1 hour ago

Yeah man if a barbarian fells a tree in the forest but nobody is around to hear it, is it still barbaric?

vlovich123•about 1 hour ago

Barbarism was just the ethnic slang Greeks had for non Greeks that Romans then adopted for non Romans. But cultures playing “I’m the best” is not new nor did it require cultural development; othering is a natural part of game theory to make sure your tribe has tighter cohesion against intruders.

hinkley•about 3 hours ago

There are stories that the moss on trees in temperate rainforests allow the tree to pull water from their branches instead of the ground, increasing their max height.

For a while there were people poaching the moss that facilitated this, which is a problem because it grows only inches per year.

ryanmcbride•about 3 hours ago

God that's sad. We really can't have anything nice.

hinkley•about 3 hours ago

It’s harder to remove the moss from high up in the tree and there are more risks in doing so. I was never clear on how prevalent this shittery was.

chasil•about 2 hours ago

Kurzgesagt has two videos on trees addressing this and other questions.

https://m.youtube.com/watch?v=ZSch_NgZpQs

https://m.youtube.com/watch?v=pHJIhxZEoxg

nomel•about 3 hours ago

This goes against all previous research/measurements for actually tall trees (looks like they only considered up to 80m) and the fact that there are exactly zeros trees in the world taller than 130 meters [1]. Wide capillaries at the base, like stated in the article, don't seem to be related.

[1] https://www.sfgate.com/science/article/REDWOODS-How-tall-can...

fc417fc802•about 1 hour ago

I agree it doesn't pass the sniff test (where are the 500 meter trees in the rainforests?) but I think it would make an excellent goal for molecularbiological and genetic engineering. We (our civilization) need to become much more skilled at that before we start editing the human germline, and we will inevitably want to edit the human germline eventually (or rather we are currently exhibiting great restraint in not doing so but I'm not sure how much longer that will last), and anyway thousand meter trees just sound like they would be really cool.

gre•8 minutes ago

> 500m

500ft is taller than the max ever, not 1640 ft

Sharlin•about 1 hour ago

There are obviously other factors limiting tree growth, like compressive strength.

cortesoft•26 minutes ago

Couldn't both things be true? Water transport is not the limiting factor, but some other thing is?

jzer0cool•14 minutes ago

Any truth to whether water pumped by tree (branches) is potable?

nullorempty•about 4 hours ago

>Giant trees have no trouble pumping water to top branches

Hm, may be because they are not really "pumping" the water?

leni536•about 4 hours ago

What would you call it?

cj•about 4 hours ago

Not that it really matters, but the article also refers to it as “drawing water to the top”. That seems more representative of reality than “pumping water from the bottom”.

chowells•about 3 hours ago

If you think of it that way, you have a real problem. It only takes about 10 meters for the weight of a column of water to create enough downward force that it starts vaporizing, at which point no pumping action works. This is why any deep well has a submerged pump. You simply can't pull water upward further than that with negative pressure in the Earth's atmosphere. It must be pushed with positive pressure instead.

This is why the question is interesting. You can't just suck water to the top of a 60 meter tree. There must be some kind of positive-pressure pumping involved.

margalabargala•about 4 hours ago

Yeah it's the difference between creating low vs high pressure.

rolph•about 4 hours ago

more like capillary action.

https://en.wikipedia.org/wiki/Xylem#Cohesion-tension_theory

card_zero•about 3 hours ago

Oh, so we don't really know how it works. Fun.

rolph•about 3 hours ago

the research is relevant to the issue of transpiration column hieght as a postulated limitation to overall hieght of any tree.

a column of water is pulled by hydrogen bonding between molecules in a tug of war fashion, the top of the column is where water is dissociated from the column at such a rate as to maintain low pressure with respect to the column[xylem]

in summary water moves from bottom to top in a transpiration stream, that ultimately ejects water vapour from the leaves, resulting in a low efficiency mechanism, that loses a lot of the water but occurs at such a rate that the low efficiency is "good enough" for whats needed.

gitaarik•about 4 hours ago

“Trees contain lots of thin, hollow vessels and they suck water upwards by creating low pressure at the top,”

So sucking / pulling?

IsTom•about 4 hours ago

So a suction pump?

m463•about 3 hours ago

on the other hand, many giant trees get the water out of the air via fog:

Coalescence of coastal fog accounts for a considerable part of the trees' water needs.[23]

https://en.wikipedia.org/wiki/Sequoia_sempervirens#Fog_and_f...

https://en.wikipedia.org/wiki/Sequoia_sempervirens

efskap•about 3 hours ago

Similarly, it blows my mind that all trees are made of air, specifically the carbon in it. I used to think that the biomass must come from the soil, but reality is more interesting.

c22•about 3 hours ago

Kind of like how the vast majority of weight loss in animals happens via exhaling.

Weirder still is the realization that all the air is just trapped light.

kijin•about 2 hours ago

Actually, all matter is just trapped energy.

kulahan•about 2 hours ago

It's also kind of weird to think that soil, really, is just ground up "stuff" that used to be trees, plants, rocks, etc.

nomel•about 3 hours ago

Sequoia are still limited in height by gravity, probably due to capillary pressures. [1] If they evolved to be segmented, they could probably do it.

[1] https://www.sfgate.com/science/article/REDWOODS-How-tall-can...

hinkley•about 3 hours ago

There’s also a theory that the moss on these trees is mutualism instead of simply epiphytic. The moss holds moisture, which can be accessed by the tree.

pkghost•about 2 hours ago

Folks still sleeping on structured water.

While admittedly contested and only reproduced by a few labs outside Gerald Pollack's at University of Washington, there is a solid case that it could play a role in transporting water and sap to the tops of trees. At least, it's involved in the motion induced in hydrophilic tubes when there is sufficient ambient radiant energy (uv/infrared).

Relevant papers:

"Exclusion-zone water inside and outside of plant xylem vessels." 2024 Scientific Reports. https://www.nature.com/articles/s41598-024-62983-3

"Surface-induced flow: a natural microscopic engine using infrared energy as fuel." 202 Science Advances. https://www.science.org/doi/10.1126/sciadv.aba0941

"Long-range forces extending from polymer-gel surfaces." 2003 Phys. Rev. E. https://link.aps.org/doi/10.1103/PhysRevE.68.031408

Pollack's site: https://www.pollacklab.org/

Some critiques of Pollack's theory:

Schurr, J.M. (2013). Phenomena associated with gel–water interfaces: analyses and alternatives to the long-range ordered water hypothesis. J. Phys. Chem. B, 117(25), 7653–7674. https://doi.org/10.1021/jp302589y Elton, D.C., Spencer, P.D., Riches, J.D. & Williams, E.D. (2020). Exclusion zone phenomena in water — a critical review of experimental findings and theories. Int. J. Mol. Sci., 21(14), 5041. https://doi.org/10.3390/ijms21145041 (open access; the most thorough critical review) Elton, D.C. & Spencer, P.D. (2021). Pathological water science — four examples and what they have in common. In Water in Biomechanical and Related Systems (Biologically-Inspired Systems, vol. 17), pp. 155–170. Springer. https://doi.org/10.1007/978-3-030-67227-0_8 (preprint: https://arxiv.org/abs/2010.07287)

theendisney•28 minutes ago

I regretably didnt save it but there was a truly hilarious topic on usenet sci.physics long long ago. If we've gathered enough evidence against something or if the thing goes against accepted consensus you are forbidden from doing further research and new evidence is no longer allowed. The topic then invited others to list such topics. The list grew to hundreds of entries and people couldnt resist getting angry reading their personal trigger words despite there being many more silly things on it.

Yours shall be filed under homeopathy :)

alldayhaterdude•about 4 hours ago

Happy for them.

lukeholder•about 3 hours ago

This made me laugh out loud. Thanks.