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Biologist Studies The Voices (And Songs) Of Trees

Courtesy of David Haskell
Biologist David Haskell says trees are communicating at all times with humans, animals, the soil and their environment.

You might have heard about people who talk to trees. But can trees speak?

Biologist David Haskell spent a year studying trees across the globe, paying the minutest attention to their movement, growth and sounds. He found trees do communicate. They communicate with the soil, the weather, other living creatures, and yes, they send out pulses like the vibrations of our vocal chords.

Haskell believes we can learn a great deal about our world and ourselves from listening to trees.

Haskell will speak about his new book, “The Songs of Trees: Stories from Nature’s Great Connectors,” Tuesday at Illinois Wesleyan University and Wednesday at the DoubleTree Hotel in Bloomington as part of the 50th anniversary of the Parklands Foundation, which seeks to preserve natural areas.

“Trees have voices in many different ways. The most obvious and most familiar are perhaps the voices evoked by the wind and rain in trees,” Haskell said on GLT’s Sound Ideas.

“Attending to the voice of trees, we can learn something about the being of that tree … Just as each bird species has its own sound and voice, and humans do, so do trees.”

As part of his research, Haskell hooked up an ultrasonic detector to branches of trees he studied.

“You could hear sounds of distress or of drought within the twig. A kind of an ultrasonic crackling sound emerges,” Haskell said.

The tree in that case emitted a tapping, similar to the sound of Morse Code.

Haskell attached another sensor to a maple twig, as water flowed through it over a 24-hour period.

“It was an analogous to the pulsing of blood through human veins,” he said.

He then converted those pulses into piano notes, making for a kind of Stravinsky-esque a-tonal scale.

“The fatter the twig, the higher the sound, the thinner the twig the lower the sound,” Haskell explained.

Trees are also engaged in a “constant dialogue” with surrounding with insects and birds, Haskell said.

“Trees are in fact humming with information,” he added.

Haskell calls trees “nature’s great connectors.”

“We are made from connections and if you take those connections away life ends,” he said.

“It is particularly true for trees. For a tree to survive to 300 or 400 years old, it has to do a great job of communicating with the other creatures around it. A tree doesn’t have the option of moving away as animals do. It is rooted in one spot and has to get along with its neighbors.”

A tree, he added, is “the nexus” of thousands of inter-connections. “Through the lives of trees we come to see we are all interconnected,” he said.

Some of those connections are happening on a micro scale, others on a global scale as trees interact with their environment.

Sometimes those interconnections are cooperative and sometimes they involve drama and tension, Haskell said.

“It’s not all a great lovefest.”

Haskell said many people don’t realize that when they hear a piece of music played on a violin, cello, guitar or viola, they are listening to the voice of a tree.

“We are hearing the work of the musician, we’re hearing the composition of the composer and we’re also hearing the particularities of the place the tree grew,” he said.

“People who make musical instruments understand they are working intimately with the details of how trees grow … So we are hearing the voice of the forest as well as the sounds of the musician and composer.”

Haskell said he connected in a special way with two the trees he studied. One stands 150 feet off the ground in the Amazon rain forest.

“Climbing into the canopy through the layers of humidity through the stinging ants and bees, hearing the voices of the monkeys and birds waking, all of this revealing itself, (it was) almost like walking up through geologic strata or layers,” Haskell recalled.

On the other end of bio-diversity spectrum is a street on a street corner in Manhattan.

“Put your hand up to the trunk of the tree after a rain has come to the city and pull way your hand and you’ll feel a slurry of ash running down the bark of the tree, almost as if tree burning,” Haskell said.

“That is all the pollutants tree has taken from the air,” so they don’t enter human lungs.

This is just one way trees “weave their way into the life of the city,” Haskell said.

Credit Courtesy of David Haskell
As part of his research for "The Songs of Trees," author David Haskell connected sensors to tree twigs to record their vocal signatures.

Haskell is critical of the way public policy surrounding the environment is currently shaped.

“It is often derived by people who have little or no knowledge of forest,” Haskell said. “People who haven’t smelled the soil or spoken with people indigenous to an area or talked with bird watchers and hunters and farmers.”

Without that kind of first-hand knowledge, Haskell said, the environmental decisions being made “are unlikely to be wise.”

“We need to reconnect people with the community of life in which we’re embedded,” he added.

One of the major conclusions of his research, Haskell said, is that all of life derives from a network of relationships. “Individuality is an illusion,” he said.

Haskell teaches at the University of the South in Sewanee, Tennessee. He is known for his creative and intensive observations of natural areas.

For his previous book, “The Forest Unseen,” he observed one square meter of a wooded area near his home in Tennessee. That book was a finalist for the Pulitzer Prize and won the 2013 Best Book Award from the National Academies, the National Outdoor Book Award and the Reed Environmental Writing Award.

Haskell will speak Tuesday on his latest book “The Songs of Trees,” at 7 p.m. in the Hansen Student Center at Illinois Wesleyan.  The talk is sponsored by the John Wesley Powell Audubon Society and the Illinois Wesleyan environmental studies program.

His talk Wednesday for the Parklands Foundation 50th anniversary celebration is at 5:30 p.m. at the DoubleTree Hotel.

You can also listen to GLT's full interview with Haskell:

GLT's full interview with Haskell.

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