From: Andrew Kenneth Fletcher
Subject: Re: How does water really reach the leaves of trees?
Newsgroups: bionet.agroforestry, bionet.plants, sci.bio.botany
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Thank you for your response to my posts and for your recognition of the
importance of the experiments. The theory I sent to you was written for
level 4 science and I was limited to 3000 words.
Given the limitations, I think I did a good job of clarifying the main
points of the theory. However it represents only a minute fraction of the
To: AndrewKenneth Fletcher
Sent: Saturday, March 04, 2000 2:51 AM
Subject: RE: NEW THEORY FOR FLUID TRANSPORT Re: How does water really reach
the tops of trees?08/August/1999
You have the honor of being a true scientist and experimentalist.
Yet you have to answer for some big questions.
1- You have to explain the results of "Strasburger 1893" who killed the
lower part of an Oak with picric acid and demonstrated that "all" the stem
raised a "Fuchsin aquatic solution".
El, I am not familiar with the above mentioned experiment and would appreciate
Acid rain causes the death of many trees. Has anyone considered the fact
that an increase in acid will cause an increase in the rate at which
minerals are dissolved. For instance, if I pour battery acid on concrete,
If you increase the amount of minerals in water, you increase the specific
gravity of said water. When you relate this to the Brixham Exp. Any increase
in the S.G. of the water contained in the upward flowing side of the tube
will reduce the flow in the downside!
If the water at the said container becomes too heavy, the experiment would
stop or at least slow down to the point of almost stopping. The tree would
face the same problems according to the gravity theory. However, if the
weather conditions promoted accelerated evaporation from the leaves, this
would compensate for the heavier water at the root and transport would
Killing the bottom part of the tree would not cause the circulation to stop,
it would not even prevent the tree from drawing water from the soil.
The xylem is after all already dead and the downward flow would simply find
another route, possibly into a xylem, or by oozing from a damaged part of
El, 2- There is an established "Cohesion theory" which explains most of your
theory and you have to show what is the difference.
I am unaware of anyone showing water flowing vertically up to 78 feet.
Correct me if I am wrong, but cohesion simply explains how water bonds to
water. I fail to see how this could explain bulk flow vertically up or down.
As for chemical reactions at the leaf causing electrical influences on water
and then effectively transporting a hundred gallons of water from the roots
of a mature oak to the leaves, just does not work for me. If it has been
shown experimentally, I will swim the ocean and shake your hand tomorrow.
Once you have observed water flowing in tubes, and I sincerely hope you will
try at least the bench-top model, you cannot deny the existence of gravity
driven circulation! The efficiency of this system sets it aside from all
other attempts to explain fluid transport.
Since 1994, I have convinced many scientists, including Professor Edzard
Ernst at Exeter together with three doctors, Professor Michel Cabanac,
University Laval, Quebec. Professor H.T.Hammel. Emeritus member of the Max
Planck Instiute, Dr David Cutler, Kew Gardens, Forestry Commission
Scientists- who also attended the Brixham Exp. Professor Chui Exeter
University. and many many more. Yet nothing happens. I also know the reasons
why nothing happens!
El, 3- If "salt solution" must "fall under gravitation to pull a water column up
and that is how the plant "feeds", how can you explain water circulation in
horizontal plants being so ordered as xylem feeding forward and phloem
Horizontal flow? If I lay a water filled tube horizontally, with salt
solution added at the middle of the tube and the ends capped off, there
would be water transport spreading outwards from both sides of the saline
solution, and in order for this to happen, clean water would be drawn
towards the centre of the salt solution.
Even horizontal plants are elevated to some degree above ground level and
roots are usually below the surface of the soil. this is all that is
required to trigger transport.
El, 4- How do you explain the homogeneity of climbing plants when they make a
down turn following the light- intensity?
The energy source in the soft part of plants would alter the pressures in
the xylem and phloem on one side of the stem, causing the plant to turn
towards the energy source.
Imagine a length of string attached to the trunk and running through soft
new growth in a tree. Give the string a pull and the branch is bent towards
which ever side the string is inserted.
El, 5- In some ground plants the stem grows horizontally on the ground and we
can see multiple root systems along the stem and multiple shoot systems as
well, How do you explain the sap streams in such a plant, where all roots
absorb water and all shoots transpire. What is the direction of the flow?
where does your theory fit?
Do you think it is bidirectional? Or do you have to admit that the dead duct
network provides the path to the living parts, where one would push and
another would pull "on demand" and on cell to cell interactions.
The new shoots and roots would set up an independent flow system, which uses
the main flow systems water to operate. Take a cutting and it grows
independently to the plant it is cut from.
The roots on such a plant face down and the leaves point up.
El, So, yes your experiment is a wonderful verification for the Cohesion theory
which explains the minimum requirement of energy for water transport in a
living plant, where mineral and sugar diffusion from production line to
assembly of polymers locations would pull the associated water along with it
and must be replaced "Cohesively".
El, 6- In many houses we have hanging pots for plant decoration in which plants
"hang down from the pot.
Do you have the slightest doubt that water in xylem is moving down and water
in phloem is moving up?
This should disprove your theory completely.
You can't disprove the truth! You can cloud its validity with words, but
clouds have a nasty habit of letting the light through at times.
Oh boy, do I have some doubts.
If I shaped my tube loop to the exact shape of the plant you refer to and
released the saline solution at the same point as the leaves would release
their sap, you would still see gravity driven circulation, from a single
cell to a giant redwood, it makes no difference to gravity. Try it!
Furthermore, if there is a U bend in the plant, roots will form at the
bottom of the loop and this is used effectively to take cuttings from some
plants by pegging a branch so that it is covered in soil.
El, So think deeply because your contribution to science is valid experimentally
but your theory is defective.
That is why I have been repeatedly encouraging you to study plant physiology
deeply and check the established theories profoundly before you postulate a
We are studying plant physiology deeply as we exchange views and I am very
grateful for the opportunity to share your knowledge.
I do have a fair bit of knowledge in this field. However my work has led me
to helping people with neurological conditions, but that should be left out
of this discussion.
El, Regardless of your theorization I must congratulate you for the wonderful
experiment that should be known by your name.
In the history of science thousands of scientists have contributed to the
bulk of experimental data.
Yet few make it to the top including Clowns like Einstein.
With best regards.
Thank you for these words, they show me that some people at least are not
shackled to the powers that be.
Your integrity is admirable.
The following review came from a letter I wrote to professor H T Hammel,
who is member of the Max Plank Institute.
Within a 2 weeks I received his reply
SCHOOL OF MEDIICINE date September 6/ 1995
Dear Mr Fletcher:
I received the information you sent me regarding your ideas about fluid
transport in trees, in tubing and in the vascular system in humans.
I will study your ideas and comment upon them as soon as possible. A Quick
scan of your Brixham experiment prompts me to ask if you conducted this
experiment with boiled water without any solute added to the tubing on
either side of the central point which you raise 24 meters? I expect that
you could raise the tubing to the same height with or without solute in the
water. In any case , your experiment confirms that clean water (water that
is unbroken water, water that is without a single minute bubble of vapour)
can support tension of several hundreds of atmospheres. The record tension
obtained experimentally is 270 atmospheres. At 10 degrees C. (c.f. Briggs,
L. Limiting negative pressure of water. Journal of Applied Physics 21:
I expect even this tension at brake point can be exceeded by careful
cleansing of the water, to remove even the most minute region of gas phase.
When the water is already broken, as occurs when gas is entrapped on
particulate matter in ordinary water, the water will expand around even a
single break when tension (negative Pressure) is applied to the water. When
you boil the water, prior to applying (2.4-1) ATM negative pressure to the
water in the highest point of the tubing, you eliminate some of these breaks
in ordinary water. I expect that dissolving NaCl or other solutes in the
water will have little or no effect on the way you measure the tensile
strength of water.
I am enclosing some reprints that may interest you. Some of these deal with
negative pressures we have measured in tall trees, mangroves and desert
shrubs. Other reprints deal with how solutes alter water in aqueous
solutions and how colloidal solutes (proteins) affect the flux of protein
free fluid between plasma in capillaries and interstitial fluid.
Sincerely H.T. Hammel Ph.D.
Gravity, Learn to live with it, because you can't live without it!
Your gravity theory is sealed...it cannot be shaken. Ha ha...plants hanging downwards....but the roots are not growing up! I have seen plants bend away from geopathic stress...and my theory is zones of geostress are disturbed gravity so the plant grows towards normal gravity!
Just came across this. They think the tree is involved in pumping. www.sott.net/article/383550-Do-trees-have-sleep-cycles
Short-term plant movements are caused by changes in water pressure within tissues. It is generally assumed that water transport in trees takes place as a steady-state process with no variations faster than the day and night cycle. The new findings suggest that short-term change in water transport and tissue pressure is widespread.
Journal article here: András Zlinszky, Anders Barfod. Short interval overnight laser scanning suggest sub-circadian periodicity of tree turgor. Plant Signaling & Behavior, 2018; 13 (2): e1439655 DOI: 10.1080/15592324.2018.1439655 dx.doi.org/10.1080/15592324.2018.1439655
Thanks, this is more proof that trees are circulating sap, rather than the "thought up" one way lift through porous leaves" Animation of branches and leaves at night can be explained with changes in pressure, as the evaporation slows down along with sap cooling.
Applying more tension to the sap on one side of a tree, and lowering the pressure of the sap in the xylem would cause the soft wood branches to bend and twist and releasing the tension and raising the sap pressure at night should cause the branches to move back in the opposite direction.
high and low humidity can also affect internal pressures.
Gravity, Learn to live with it, because you can't live without it!