Our today's doctrine of hydraulically drawn water transport in plants is wrong. It is based for tall plants on experiments with artefacts similar to those of the adjacent figure ("Fig. XI") by J. Hales (1726).
The obvious question to cut plant fragments, which are fixed watertight in glass tubes or glass capillaries, is: how can these artefacts pull up water in the glass tube? Actually, one wants to know: how do intact plants transport the water absorbed through the roots?
On closer examination, it can be seen that the experimental setup shown cannot answer the question of the actual plant water transport. As a result of the accompanying, frequently repeated experiment, the glass tubes/capillaries filled with water were thought to have their hydrodynamic properties in the plant body. This leads e.g. in trees for the assumption of: ".. water threads hanging from the evaporating leaf cells, ..." (J. Böhm 1893, translated from German), which are thought of from the crown to the root as continuous and held together by cohesion forces (so-called "cohesion-tension theory").
The physical flow law of Poiseuille derived empirically from glass capillaries should also apply in plants. Ignored must be the physical fact that over 10 meters high, stretched water threads already boil at normal temperature. If they do not boil in rare cases, they are in a very unstable state - a so-called metastable state. Also, the normally omnipresent in xylem existing steam/gas portions hanging water threads would interrupt.
In the following, a natural, sorptive transport principle for the intact plant body is described. The water is held and moved in nature and contrary to the textbooks, almost free of tensile stress in each plant height. As is known, water in a liquid manner enters the hermetically sealed conducting organs of the plant (xylem/wood) by diffusion processes and exits in vapour form via the leaves by diffusion.
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