As I foraged firewood from the woods behind our house the other day, a persistent chirping/squeaking pierced the air.

Pileated woodpecker? Red-shouldered hawk? Chipmunk? Fox?

Tiptoeing toward the sound, I continued to review my recollection of bird and animal calls. Something about this particular cry was a little off — not exactly a squeal, squawk, hoot, screech, cheep, yelp, bark or yap. But what?

In 50 yards, I had my answer: A dead oak, evidently knocked precariously off-kilter by a gust, rubbed against a live maple.

All sound is vibration, whether produced by drawing a violin bow over a Stradivarius string, expelling air over vocal cords, or abrading tree trunks.

One more puff of wind could send the teetering tree crashing to the ground, or worse, in my direction. I wondered: If a tree in the forest falls on an unsuspecting woodman, and nobody is around to hear it, would it make a sound?

During the rest of the afternoon, I detoured around the wiggling oak and repeatedly glanced overhead for other wooden swords of Damocles. Damage from gypsy moth caterpillars, ash borers and bittersweet vines have combined with increasingly violent, climate-change-driven storms to create an overstory minefield.

Not far from the leaning oak, I encountered an enormous tulip poplar, snapped in half. The jagged trunk near the base remained standing, while a 50-foot section that extended to the crown lay on the ground, directly across a path that I had strolled on just a day before.

A week earlier, another oak limb, as thick as an elephant’s leg, had broken off and knocked several boulders loose from a stone wall. It looked like a cruise missile strike.

The peril of toppling trees notwithstanding, at least there’s plenty of free firewood, if you don’t mind all the cutting, splitting and stacking. Why pay $290 for a cord when there’s literally a windfall at your feet? Likewise, why shell out $34.95 for a sack of Georgia fatwood kindling, or $20.88 for a box of fire-starter bricks, when heaps of sticks and branches, perfect for getting a fire going, cover the ground just outside the back door?

The rewards of abundant firewood aren’t just financial. Friends and I hike, run and kayak year-round; after a frosty day outdoors, nothing beats warming up next to a wood stove. On the other hand, few experiences are more dismal than crawling out of bed at 3 a.m. to stoke the stove after the fire has dwindled to embers. There also are ashes to shovel, dust to sweep, stovepipes to clean, and logs to lug, to and from the woodshed.

Like the proverbial free lunch, there’s no such thing as no-cost firewood.

My rule of thumb is there’s no such thing as too much firewood. Even with 10 cords split, stacked and stored in adjoining woodsheds — enough to keep our house toasty for the next two winters — I’m always on the lookout for more fuel.

With this in mind, I considered bringing the teetering oak the rest of the way down, but paused. The job would require tricky and risky undercutting.

You know, the chirping/squeaking is a rather pleasant sound after all. When the wind is right, I can hear it a quarter-mile away.

Sooner or later, though, gravity will prevail over friction, and there will be a thud. I hope to hear it, from a distance.