Our friend’s passive solar house was built on a Pennsylvania hilltop more than 30 years ago. The open interior architecture showed off the large stone wall that captured heat from the many windows. The rough-hewn beams and plank flooring completed the handsome, rustic feel of the place. Outside, the wood exterior had weathered beautifully.

Unfortunately, his happy home had a recurrent problem every spring.

Like clockwork, each sunrise was accompanied by a loud rapping just outside his bedroom window. A hairy woodpecker (Picoides villosus) was industriously drilling away at the wooden exterior.

Hairy woodpeckers are the super-size cousin of the much more common downy woodpeckers.

Both species have identical black and white patterns on their heads, and both have all white backs. The black-and-white wing patterns are also identical. Males of both species have a red head patch.

At a little more than 9 inches from bill to tail, hairy woodpeckers are about one-third larger than downies. The larger bird also weighs twice as much as the smaller.

The pointed bill of the hairy is proportionately longer than the rather stubby bill of the downy. The sturdy black tail of the hairy is usually bordered with all-white edges. Downy tails are black with black-and-white edges.

The noisy intruder at my friend’s house was a male. Every spring, these fellows will hammer away at hollow limbs — or loose boards! — as a way to mark their territory and attract a mate. They are especially active at daybreak.

In addition to their procreative rapping, hairy woodpeckers drill for their dinners. About 75 percent of their diet consists of beetles and other insects, most of which are found in damaged or rotting wood.

Recently burned forests are hairy woodpecker hotspots, where they can often be seen drilling on tree trunks or major limbs.

Feeding on tree insects isn’t easy. The bird must do more than simply drill a hole. It needs to extend its sticky tongue along the tiny tracks that boring insects leave in their wake. That’s where the evolutionary wonder of the hairy woodpecker’s tongue comes into play.

Although the hairy woodpecker’s bill is relatively long, it’s inadequate to hold the entire tongue. Amazingly, the tongue extends to the back of the skull and then loops back around the right eye. When seeking food, the woodpecker flicks its curled tongue deep into crevices to capture all manner of bugs.

These woodpeckers often drill their own nests. In just two weeks, they can excavate a 1.5-inch hole with a sizable cavity. About 9 inches is cleared below the hole and a few inches above.

Hairy woodpeckers produce one brood annually. The female lays about four eggs and incubates them for 11–12 days. The helpless chicks remain in the nest for a month before they are ready to fend for themselves.

Hairy woodpeckers are widespread in North America. Ornithologists estimate that more than half can be found year-round in the mature forests of Canada, from coast to coast. About 44 percent of the birds are year-round residents of the United States, with the remainder scattered through the mountains of Mexico and into Central America.

The birds show some noticeable regional variations in color.

Throughout the Chesapeake region, hairy woodpeckers are white below and have extensive white spotting on their wings.

West of the Rockies, birds have less spotting and the bands of white on their faces are narrower.

In the Pacific Northwest, the white parts are replaced by a tea-colored brown.

The wood-pecker hammering outside my friend’s window was a male and he was establishing territory. Some homeowners have a more critical problem than lost sleep. The hammering could be for feeding purposes, indicating that the wood was infested with insects, perhaps termites.

There are dozens of remedies to rid a home of an unwanted guest at 6 a.m. every day. People use inflatable owls, dangle CDs on strings and play recordings of hawks.

Cornell University’s Ornithology Lab reports that streamers worked better than other common remedies, but even they are often ineffective.

A high-ladder investigation reassured my friend that insect infestation wasn’t what attracted the woodpecker to his house. The hammering was purely territorial, and over the years, he adapted to the avian reveille.

This friend had planted 600 trees on his surrounding land. The exact habitat for hairy woodpeckers was growing on his homestead. Last year, the forest was mature enough to provide other sites for early morning woodpecker displays. Now he awakens to distant, muted drilling.

I wonder what kind of a world we would inhabit if more people were this far-sighted and patient in the face of life’s challenges.

Surely it would be a world in which we would all sleep easier.