A woodsy fragrance has lingered in Oakland for days, and the windows and doors that usually invite cool, seasonal air to waft through homes and apartments have been kept shut.

The pungent air spooked Sue Piper and Carolyn Burgess before dawn on Monday.

The Oakland hills neighbors wondered if the smoke was coming from their backyards, because they know it will happen again.

Both Piper and Burgess lost their homes in the 1991 Oakland hills fire that killed 25 people and destroyed 3,500 houses. But what they smelled this week was smoke from the fires roaring through Wine Country, deadly infernos that had parts of the East Bay wrapped in an opaque haze.

The small fires that burn in the East Bay hills every summer are a habitual way of life, not unlike waiting in an hour-long line for a table at a popular brunch spot on the weekend. But Piper and Burgess know that wildfires like the 1991 firestorm happen once every two to three decades in the hills.

“We are overdue,” Piper said.

Still, many of their neighbors might not be in the know because the proportion of residents who rebuilt after the fire and still live in the hills has significantly thinned. And there’s been new development.

That’s why Piper and Burgess have been focused on keeping their neighbors vigilant.

“We’re the first line of defense,” said Burgess, public safety chairwoman of the North Hills Community Association, which pushes for disaster and crime safety.

Piper, president of the Oakland Firesafe Council, a group of hills fire survivors that advocates for fire safety, said she believes homeowners in the hills have a responsibility to each other to keep their properties properly groomed.

“Our neighborhood is only as strong as our weakest link,” Piper said just before getting an automated phone call with a foreboding message.

At the same time, Burgess also received a blaring push notification to her iPhone: The National Weather Service had issued a red-flag warning for the East Bay hills because of the low humidity and gusting winds. In other words, ripe fire conditions.

We were sitting at Piper’s mahogany dining room table, one of the first furniture purchases she made after her home was reduced to smoldering ashes.

When it’s dry and windy like it has been this week, Piper and Burgess become alarmed. Before she drove to Piper’s Hiller Drive home with its Redwood exterior, Burgess, who lives on Tunnel Road, raked up pine needles.

On the day we met this week, Piper and Burgess visited Oakland City Hall to discuss wildfire prevention. They’ve long had concerns about the veracity of the city’s inspection process.

Burgess took me for a drive through the hills to show me what they meant, pointing out properties that appear to flout compliance by allowing tree limbs and leaves to overhang structures.

Once a fire gets to the crown of a tree, the disastrous domino effect — from crown to crown to roof to roof — is nearly impossible to stop.

As we drove the narrow and curvy streets, including Charing Cross Road, where almost half the people who died in the 1991 fire were caught in a colossal traffic jam, we passed wild turkeys meandering in the road. What really caught my eye was the dead tree trunks on hillsides, the perfect food for a hungry blaze.

“We cannot be in denial,” Burgess said. “We’re trying to also help educate people. We want them to know what they should be preparing for.”

The point Piper and Burgess made: It’s not just on the city to monitor fire hazards in the hills.

“Homeowners have to own the fire,” Piper said. “We’re responsible for making sure our house has defensible space.”

That means keeping a healthy clearing — no brush, large trees or dead vegetation — around a property.

That means keeping gutters clean so embers don’t land in a Goldilocks-perfect bed of leafy tinder.

“We were inspected in June. Well, stuff grows,” Piper said. “It’s not (just) the city’s responsibility. It’s my responsibility as a homeowner.”

And her responsibility as a good neighbor.

Because if — no, when — there is another firestorm in the hills, it will be the neighbors who will have to work together to push each other down the hill.

“You need to know who your neighbors are because, in a disaster, we’re the ones who are there,” Piper said. “Because the fire department and ambulance, in that kind of situation, they can’t get here.”

San Francisco Chronicle columnist Otis R. Taylor Jr. appears Mondays, Wednesdays and Fridays. Email: otaylor@sfchronicle.com

Twitter: @otisrtaylorjr