Ten thousand years ago, a fierce wind struck southern Massachusetts and an old and great white pine collapsed. Down it fell with a splash, sinking into the cold wet muck at the bottom of a pond it bordered.

Mysteries of Vineyard forests were revealed in a walk last Sunday afternoon at Felix Neck Wildlife Sanctuary. More than 10 naturalists took a walk with Beth Schwarzman, a Falmouth writer, geologist and savant who, like a detective, can read the hidden tales within ancient landscape.

Every forest has a tale, Ms. Schwarz-man said, though it may not be an obvious one. In this region, the natural progression of plants is towards forest — so whatever its previous use, land left alone becomes forest. What plants dominate that forest can offer clues to its past life.

For Polly Hill Arboretum director Tim Boland, the swift demise of his oak forest that spans the arboretum property has been literally startling. “I’d be outside in the collections this winter and I would just hear wha-BAM!” The trees, ravaged by a plague of caterpillar infestation that lasted just over three years from 2005 to 2008, are now hollowed and rotting, teetering toward collapse. “I used to think these trees would stand for the next 10 years or so. They won’t. Within the next three to four years they’ll all be down,” Mr.