To the landscape contractor, the leaf blower is a gift from God. To many others, it’s an abomination. (iStockphoto)

There was a time when the defining sensory aspects of an afternoon in the autumn garden were the scratching sound of the leaf rake and the scent of leaf-fueled bonfires.

The bonfires have gone from most places — too polluting — and the rakes are silent, largely. Since the 1970s, the soundscape has been shaped by the leaf blower. To the landscape contractor and estate gardener, the leaf blower is a gift from God, saving hours of tedious raking and grooming. To many others, it is an abomination. When a neighbor’s mow-and-blow brigade arrives, with two or three gasoline-powered blowers fully vented, it is as if the banshees are in the ’hood. Banshees, you may know, are spirits whose wailing prefigures a death, in this case the passing of the quaint idea that people should be left in peace in their own homes.

I dislike leaf blowers, but I have one, and not just a wimpy handheld device with an orange electrical cord. Mine is a gas-powered backpack blower. This may mark me as a hypocrite, but let me explain. The machine is used infrequently and for the most part at its quietest idling speed. Even throttled down, the airflow is sufficient to move debris, and the blower shifts leaves and twigs without disturbing the underlying gravel path in a way that a rake could not. If you have fallen leaves on a newly seeded lawn, the blower can be used to clear the new lawn gently without disturbing the grass seedlings in a way that a rake would. If the blower broke tomorrow, I probably wouldn’t replace it.

But we are getting stuck in the weeds.

There is a weird human phenomenon at work here: Sound is far less irritating to its creator than to its recipient. Erica Walker, a doctoral student at Harvard University’s Chan School of Public Health, seems to have hit on one reason for this: Recipients of nuisance noise have no power over it.

In a survey of 1,050 residents of more than a dozen Boston area neighborhoods, she reported that the overwhelming majority of respondents said they could not control noise or get away from it. “That’s a very vulnerable place to be in,” Walker said. Almost as many — 79 percent — believed that no one cared that it bothered them.

Walker, armed with a bicycle and a sound level meter, spent a year recording noise levels at 400 locations across the city. The aural irritants go far beyond the leaf blower: Airplanes, buses, trains, loud-talkers, barking dogs, blaring music — all form ingredients in the sour stew. But the leaf blower is a major culprit. The most powerful models can create a stream of air exceeding 200 mph and with noise levels as high as an ear-piercing 112 decibels.

Industry groups say the gasoline blower is getting a bum rap — that modern technology has made them far cleaner and quieter than they used to be.

One facet of this problem is that as residents have turned over care of their yards to landscapers, what was once a weekend phenomenon from a gadget-minded homeowner is now a weekday, day-long assault on neighborhoods. Another gripe: A tool thought of as an instrument of the fall has become a three-season mainstay for crews who equate a speck-free lawn, patio and flower bed with a job well done.

The two-stroke blowers are also highly polluting, said Ruth Caplan, a civic activist in Cleveland Park and a member of a group lobbying against them, Quiet Clean D.C.

“We are concerned not only about the impact on neighbors but also on workers and feel this hasn’t been given the attention that it needs,” she said.

In a recent paper written with Jamie Banks, of an organization named Quiet Communities in Lincoln, Mass., Walker measured the sound from a commercial-grade gasoline blower at various distances. Even from 800 feet away, the noise was above the 55-decibel threshold at which sound is considered harmful by the World Health Organization, she said. Another problem is that the machines emit a low-frequency sound that is not measured conventionally but which travels long distances and penetrates building walls.

Some jurisdictions have laws banning or restricting leaf blowers. In the District, council member Mary M. Cheh of Ward 3 has introduced a bill that would outlaw the noisiest and most polluting blowers after 2021.

Most cities and counties don’t address blowers specifically but have noise ordinances that ostensibly establish when and how much noise can be made before running afoul of the law. You will find if you put it to the test that local authorities as a rule are unable to effectively enforce the laws. Assuming a city even had a squad ready to show up at a moment’s notice equipped with sound sensors, “by the time the police or someone would come, the noise would be long gone,” Caplan said.

Fueling this ineffectiveness is a mind-set that if you live in an urban environment, you put up with noise. The other fallacy, said Walker, is that noise is a simple annoyance. She rejects both assertions. Cities don’t have to be cacophonous, she said, and noise isn’t just an irritant; it harms one’s health. Studies have shown that tens of millions of Americans are at risk of hypertension and heart disease from the effects of noise.

“We are blind to the fact it’s most likely causing significant health effects,” Walker said.

What has to change to make America quieter?

Caplan and others are hoping the new technology of quieter, battery-powered leaf blowers will become the norm. “We are moving quickly in that direction,” she said. Legislation such as Cheh’s will help make it a reality, she said.

Walker says beyond these steps, we need a fundamental shift in how we regard noise so that society sees it on the same plane as the environmental imperatives of recycling and reducing air pollution.

She was drawn to this field of study after living in an apartment building where small children were running on the floor above, night and day. “One of the ways that made it tolerable was my landlord saying, ‘I understand. I’m going to install carpet above you.’ It changed the noise level, but not by much, but it helped,” she said. “People want to know you’re hearing them, and taking their voice seriously.”