IDing a tree by ear alone

[Jodie]

I am reading a very irritating book, full of unsupported assertions that sort of thing, about
how great gardening is (picked it up 2ndhand, cheaply) but there was one bit in it that
intrigued me.

"Every one of the one hundred thousand types of tree on the planet sings its own song.
I enjoy the sound of a rustling aspen, the one tree I can identify by ear alone. I stand in
awe of those nature lovers who claim, as Thomas Hardy did, to be able to identify trees
by the sound of their leaves. As Hardy wrote in Under the Greenwood Tree: 'To dwellers
in a wood almost every species of tree has its voice as well as its feature. At the
passing of the breeze the fir trees sob and moan no less distinctly than they rock; the
holly whistles as it battles with itself; the ash hisses amid its quiverings; the beech rustles
while its flat boughs rise and fall. And winter, which modifies the note of such trees as
shed their leaves, does not destroy its individuality.'"

My first reaction is "pull the other one" but I thought I'd ask if anyone thinks this is
remotely possible - although I think I'd want a controlled trial to remove the influence of
lucky and educated guesses as well as chance

The book in question is "The therapeutic garden" by David Norfolk. Bits of it are very
interesting and storyish but it offends the scientist in me

Having said that, I am enjoying it.

 

[JonnyP]

Sounds like a load of pants to me Jodie, but I used to know a blind person and was always amazed at what his hearing could do, so who knows, maybe.....
Trees certainly make a sound in the wind thats for sure....

 

[Jodie]

Yes I think Thomas Hardy might have had a rather overactive imagination

I went to a science exhibition the other night in which sound waves are being used to test
the quality of wood before the tree has been cut down. So this week is all about hearing
trees for me hehe.

 

[janiepopps]

The hippy in me totally gets this!

A doctor I studied with in Shanghai would prescribe Tai Qi under a specific tree type to patients based on their therapeutic energetic values ( s.orry Jodie the Scientist ) The patients loved it and were quite open to this being part of their treatment plan!

I think that if you spent enough time away from brain draining computers tellys and other influences that cut us off from 'natures reality' and were able to live amongst trees its not impossible to believe that you could learn to hear and even feel there individual signatures.

j

 

[Jodie]

In my old flat I used to love sitting in my room when it rained and opening the windows
to listen to the rain on the trees. There were a lot of trees with dense foliage so it was
a lovely sound - also not bad on a dry day with a bit of wind. Couldn't tell you which tree
was which though

 

[SOAR]

Sounds like a good theory I know willow has a very dry rustley noice to it to me but I think if i sat down and really listened they could all have their own sound. I know that when it is going to rain trees show the backs of their leaves, dont know why?.

 

[jon r]

I could identify an aspen tree from the rustle of the leaves. The leaves do seem to move with the slightest of wind!

 

[Dynamite Dan]

as a person who works with physics on a daily basis, i can say that being to identify a certain type of tree just by the sound it makes when blown or rained upon, is impossible.

here is why i say that..

sound is just vibrations in the air, air is a very unstable product, its humidity and heat is constantly changing, sound will travel through air differently depending on its condition, warmer air can hold more moisture, so the sound waves will travel faster through it as sound travels faster through water that it does air (4 x faster if memory serves me right)

So the sound you hear from a rustling tree can change rather dramitcally depending on the surrounding climate.

Obviously small and large trees sound different due to the number of leaves that can reflect and absorb sound waves, but this is based on trees of similar size (age).

 

[leon-1]

here is why i say that..

sound is just vibrations in the air, air is a very unstable product, its humidity and heat is constantly changing, sound will travel through air differently depending on its condition, warmer air can hold more moisture, so the sound waves will travel faster through it as sound travels faster through water that it does air (4 x faster if memory serves me right)

So the sound you hear from a rustling tree can change rather dramitcally depending on the surrounding climate.

If that is the case how can I tell who is speaking and what they are saying when I change environment from arid to humid. From what I recall frequencies have a number of factors to play in the way that sound travels through water as well.

Obviously small and large trees sound different due to the number of leaves that can reflect and absorb sound waves, but this is based on trees of similar size (age).

This does not make sense "small and large trees sound different" followed by "but this is based on trees of similar size (age)"

If you take a piece of paper and run air over it at a specific speed it produces a noise which is based on the frequency that the piece of paper vibrates at. If you change the size of that piece of paper, but not the shape, to get the same sound out of it you require to change the air flow / speed of air flow.

If you change the shape of the piece of paper, but use the same airflow the vibrations that it makes in the air will be of a slightly different frequency.

If you apply that same theory to trees and leaves, being that each tree has a different shaped leaf (even though one tree may have leaves of varying size) that the individual type of leaf may produce a different sound.

So thinking along the lines that the human voice box produces air vibration at specific frequencies what you are saying that the speed of sound changes in various arid or humid conditions and as such the way we sound changes. What I think is that even if the speed of sound changes the vibrational frequencies of our voices or other constants don't.

Malleus, incus, stapes and the timpanum pick up vibrations which are then transmitted to the inner ear, these are then passed through liquid in the inner ear and the hairs in this liquid then transmit an electrical impulse to the brain as a frequency, the brain then translates that to what we think of as sound. There is probably no scientific way to prove that each tree has its own sound, however to discount it would not be sensible.

You may actually be able to group family types of tree (various members of the pine or spruce family) against others by their leaf shape and the sound produced by that shape of leaf.

 

[Marts]

This concept sounds perfectly plausible to me. After all - think of the thousands of similar sounds we can differentiate between as we go about our daily lives. If you spend your life away from the modern cacophony I suspect it would be quite possible to differentiate species of tree by sound. Probably you could also tell the season from the changing sounds of an individual species (Of course you'd be a pretty sh*t local if you kept forgetting what season you were in )

 

[Pippin]

as a person who works with physics on a daily basis

Sorry mate, but quoting your qualifications as a justification is just another invalid proof; I've got a PhD in maths and numerous publications in international journals - so what, that doesn't make me better qualified to comment on the possibility or otherwise of this

But I do know that, to take two extremes, the sound made by pine needles is different to that made by horse chestnut leaves

 

[janiepopps]

as a person who works with physics on a daily basis, i can say that being to identify a certain type of tree just by the sound it makes when blown or rained upon, is impossible.

here is why i say that..

sound is just vibrations in the air, air is a very unstable product, its humidity and heat is constantly changing, sound will travel through air differently depending on its condition, warmer air can hold more moisture, so the sound waves will travel faster through it as sound travels faster through water that it does air (4 x faster if memory serves me right)

So the sound you hear from a rustling tree can change rather dramitcally depending on the surrounding climate.

Obviously small and large trees sound different due to the number of leaves that can reflect and absorb sound waves, but this is based on trees of similar size (age).

Have you ever thought that, just possibly, we can't see or measure everything?

On paper it may be implausible for the human ear to differentiate certain trees. Doesn't mean its impossible.

j

 

[Dynamite Dan]

wow, i think i may have annoyed some people here.
and for that i apologise, i should have typed "here is why i THINK this"

I respect your PHD in mathematics, as my brother is studying for one now and i know how hard they are to achieve. By no means did i mean to come across as "i am right, everybody else is wrong"

My post was based on what i know about air moving across a surface, and how air densities affect the speed of sound (i make and repair aircraft for a living, especially the wings)

Its hard to put down in words sometimes, what i mean to describe, and this and my ignorance has got me in trouble here

please don't think im a bad person, im not.

Again my apologies.

 

[Pippin]

Sorry if I came over harshly - not my intention at all!

It's easy to over-analyse rather than just experience - next windy day, go and listen to the trees!

One of the walks I do with the dog takes me through different types of woodland, some inhabited by slender birches, other parts with majestic oaks. Even on winter evenings when it's dark, I always know how far through the walk I am - and this thread has got me thinking that part of the reason I know where I am is because of the different sounds, as well as all the other cues

I really don't think you're a bad person, and please don't think you have to apologise to this old curmudgeon!!

 

[janiepopps]

wow, i think i may have annoyed some people here.
and for that i apologise, i should have typed "here is why i THINK this"

I respect your PHD in mathematics, as my brother is studying for one now and i know how hard they are to achieve. By no means did i mean to come across as "i am right, everybody else is wrong"

My post was based on what i know about air moving across a surface, and how air densities affect the speed of sound (i make and repair aircraft for a living, especially the wings)

Its hard to put down in words sometimes, what i mean to describe, and this and my ignorance has got me in trouble here

please don't think im a bad person, im not.

Again my apologies.

Oh Dan, I was really hoping you were one of those blinkered old scientific types that saw the world in a series mathmatical equations only, ie anything that wasn't measurable therefore didn't exist. Now it seems you're just a nice guy open to other possibilities. How dull.....

How about this one then, I have (and my mum of 63 has also) walked barefoot across hot coals with an (estimated) temperature of over 1000 degrees.
How the hell does that work...

 

[bloodline]

they make em tough in Cornwall dont they J seriously though I get a different feeling depending which type of tree I am under I like most but I really like Fir trees best. It may be years of conditioning based on safety, comfort, etc

 

[leon-1]

wow, i think i may have annoyed some people here.
and for that i apologise, i should have typed "here is why i THINK this"

I respect your PHD in mathematics, as my brother is studying for one now and i know how hard they are to achieve. By no means did i mean to come across as "i am right, everybody else is wrong"

My post was based on what i know about air moving across a surface, and how air densities affect the speed of sound (i make and repair aircraft for a living, especially the wings)

Its hard to put down in words sometimes, what i mean to describe, and this and my ignorance has got me in trouble here

please don't think im a bad person, im not.

Again my apologies.

Dan, don't take it personally, if it had been anyone else they would have received the same reply. We are not here to bite peoples heads off and if I was annoyed I would of used emoticons to show it.

Your knowledge on airframes and how the varying/differing windspeeds travelling above and below a wing and how that produces lift is far greater than mine.

I spent a bit of time working with radios, and with lasers and as such know a little about frequencies and powers. For a while I used to convert dB's to Watts in my head (decibels being a logarithmic expression of power over watts being a linear expression of power).

We all tend to talk about things we know about or can figure out, sometimes we make mistakes and are corrected, I could be wrong and you could be right, but I will tend to believe more on the line that sound as are both light and radio waves attenuated by differing factors. They do however stay the same apart from their power levels be it measured in Watts or decibels.

 

[janiepopps]

Ha ha, yup. Tough as old boots :AR15firin

Truth is I cannot how see how we can claim to have all the knowledge when science itself is an ever expanding and adapting entity.

For years acupuncture has been dissed by the western scientific community until they recently 'proved' it worked by their own modalities. Surely if the treatment has withstood 4000+ years of usage and easing of physical pain, the fact of science being unable to measure its worth for the past 100 years or so is irrelevant...? I'm s.orry all science based folk out there, I'm not having a go just stating my belief that anything is possible.

j

 

[Porcupine]

if sound was "only" sound you wouldnt recognize peoples voice either.

possible? yes, probable? nah.


dont forget people can do weird things, i remember seeing someone on tv that recognized LP's by the pattern of the grooves. ( 20 randomly pulled out of a 3000 recordings )

in the end it is how much time you are willing to invest.

 

[gregorach]

Surely if the treatment has withstood 4000+ years of usage and easing of physical pain, the fact of science being unable to measure its worth for the past 100 years or so is irrelevant...?

By that reasoning, traditional Gallenic medicine, as practiced in Europe for a couple of thousand years (you know, the doctrine of the Four Humours, bloodletting, etc) is better than modern medicine. If you fancy leeches and injections of elemental mercury, knock yourself out - but don't expect many people to join you.

The fact is that the informal heuristics used to develop these systems are appallingly inaccurate. Many of the "treatments" practiced before the development of modern scientific medicine were worse than the conditions they were intended to treat.

Case in point - Chinese traditional medicine. It turns out that many of the compounds used actually contain dangerous levels of highly toxic elements such as lead, arsenic and mercury.