The Mystery of Trees Trunks Murmur and how to turn it into Music

Have you ever wondered how water makes its way up from the soil into the leaves of a tree? This seemingly simple question has puzzled scientists for decades, and the answer is far more complex than you might imagine.

So far, all we know is that water moves from roots to leaves through capillary action and transpiration.
The capillary action means that the narrower the vessel, the higher the liquid can rise against gravity. And the vessels that transport water in trees are very narrow indeed: they measure barely 0.02 inches across. Conifers restrict the diameter of their vessels even more, to 0.0008 inches. But that’s only one side of the coin because not even in the narrowest of vessels, there is enough force to account for a rise of water to a 300 feet tall tree.

So here comes in scene another phenomenon: transpiration. In the warmer part of the year, leaves and needles transpire by steadily breathing out water vapor. In the case of a mature beech, the tree exhales hundreds of gallons of water a day. This exhalation causes suction, which pulls a constant water supply up through the transportation pathways in the tree. The water molecules bond and pull each other a little higher up the trunk.

Last but not least, osmosis comes into play. When the concentration of sugar in one cell is higher than in the neighboring cell, water flows through the cell walls into the more sugary solution until both cells contain the same percentage of water. And when that happens from cell to cell up into the crown, water makes its way up to the top of the tree.

The perfect time to listen to the tree murmur

In spring, before the leaves open up, water shoots up the trunk with such force that if you place a stethoscope against the tree, you can actually hear it.

But you also can hear the tree murmur at night. Scientists from three institutions (the University of Bern; the Swiss Federal Institute for Forest, Snow, and Landscape Research; and the Swiss Federal Institute of Technology in Zurich) listened and registered a soft murmur in the trees. Above all, at night, when the water is held almost completely immobile in the inner transportation tubes, as the tree takes a break from photosynthesis and hardly transpires at all.

So, where are the noises coming from? The researchers think they are coming from tiny bubbles of carbon dioxide in the narrow water-filled tubes. Bubbles in the pipes? That means the supposedly continuous column of water is interrupted thousands of times. And if that is the case, transpiration, cohesion, and capillary action contribute very little to water transport.

So, back to the initial question. What causes the noise in the trunk?

Solve the mystery of tree sounds by turning them into music

As science is trying to catch up with explanations for life’s great mysteries, you can simply tune in and enjoy them. At the end of the day, logical answers don’t necessarily have the power to change what and how you experience this life. Your decisions and openness do.

Go into a forest at night and stick your ear to a trunk. Grab you’re your Ginko or Bamboo and turn murmur into music to take with you wherever you go. And then, in that space, you are opening for yourself and the tree, you’ll find all the answers.

Only those attuned to nature signs and have patience may experience this kind of magic. Are you one of them?

Find out how our devices turn plant sounds into music, here.