Spruce forests show shared electrical response to solar eclipse

Spruce forests show shared electrical response to solar eclipse
by Simon Mansfield
Sydney, Australia (SPX) Apr 30, 2025

A global team of researchers has discovered that spruce trees not only respond to a solar eclipse but appear to anticipate it, with bioelectrical signals becoming synchronised across entire forests hours before the celestial event.

The study, published in Royal Society Open Science, reveals that older trees exhibited the earliest and most pronounced reactions, implying they store environmental memory that may play a role in communicating upcoming events to younger trees.

"This study illustrates the anticipatory and synchronized responses we observed are key to understanding how forests communicate and adapt, revealing a new layer of complexity in plant behaviour," said Professor Monica Gagliano of Southern Cross University, a co-lead author.

Employing ruggedised, low-power sensors distributed throughout a spruce forest in the Dolomites of northern Italy, the research team tracked bioelectrical activity in real time. Their recordings showed that trees gradually began synchronising their electrical signals hours ahead of the solar eclipse.

According to co-lead author Professor Alessandro Chiolerio from the Italian Institute of Technology and the University of the West of England, advanced analytical techniques were key to the findings.

"By applying advanced analytical methods-including complexity measures and quantum field theory-we have uncovered a deeper, previously unrecognised dynamic synchronisation not based on matter exchanges among trees," he said.

"We now see the forest not as a mere collection of individuals, but as an orchestra of phase correlated plants."

The researchers suggest this synchronisation resembles a form of communication among trees, likened to the so-called "wood wide web," whereby plants interact through subtle physiological or bioelectrical means rather than traditional matter exchange.

Professor Gagliano said the data highlight the importance of preserving old-growth forests.

"The fact that older trees respond first-potentially guiding the collective response of the forest-speaks volumes about their role as memory banks of past environmental events," she said.

"This discovery underscores the critical importance of protecting older forests, which serve as pillars of ecosystem resilience by preserving and transmitting invaluable ecological knowledge."

Research Report:Bioelectrical synchronisation of Picea abies trees during a Solar Eclipse