These oaks sing to me when I am working in my garden.
A lifetime of singing can leave physical effects on the body. The evidence of wear and tear is there, but the singing goes on.
The song is in the ear of the beholder of course. It's possible that all these trees do is squeak in the wind, just like it's possible that I sing loudly and off key when alone in the JEEP with Jimmy Buffet blasting from the dash.
I call it singing.