Image source, Getty Images Image caption, Autumn can be a noisy time when the leaf blowers are out
Part of the soundtrack to a day in southern California is the drone of petrol-powered gardening equipment.
Noise is one of the main reasons that cities around the US , external are banning petrol landscaping tools or encouraging electric alternatives.
These alternatives have the additional benefits of reducing carbon emissions, vibrations and the exposure of landscapers to pollution.
In addition they can mean longer working hours, as they can be used at times when residents demand quiet.
Today, I'm taking part in training run by the American Green Zone Alliance (AGZA), an organisation supporting the transition towards electric landscaping equipment.
To my surprise, the electric backpack leaf blower I strap on is not much heavier than my normal rucksack. Using the blower to herd balls around the park feels fairly intuitive, though naturally I'm much clumsier and slower than the pro landscapers.
As for noise, there's still a buzz, but the sound is higher-pitched and not quite so loud as the familiar petrol-powered machines.
The move to electric power is attracting new companies to the market for gardening kit.
US aerospace start-up Whisper Aero is one of those firms. Its main business is electric propulsion systems for aircraft.
But in 2022, after the Covid-19 pandemic made many people more sensitive to noise, and following a couple of years of research and development, the company realised that its aerospace-grade fans would work well in leaf blowers.
"Our technology is cleaner, quieter and more efficient than other air-moving technologies that exist today," according to Andrew Terajewicz, Whisper Aero's director of air management. "And the leaf blower is the perfect mix of this."
The battery on Whisper Aero's blower lasts up to 50 minutes at full power.
The company has had to scale up its manufacturing volume in its expansion to consumer technology.
Online pre-orders of Whisper Aero's handheld leaf blower started this year. It's priced at the high-end of electric leaf blowers, which are often more expensive than traditional petrol versions.
But for that you get a machine which is less likely to disturb the peace.
"It is so ultra quiet yet powerful, that the brain has a hard time understanding what's happening," says Dan Mabe, the former landscaper who founded AGZA.
Whisper Aero aims to further develop its products, including a backpack leaf blower that would be better suited to professional landscapers.
Image source, Whisper Aero Image caption, Whisper Aero's leaf blower is based on its electric propulsion for aircraft
Even with innovation like that, petrol-powered machines are unlikely to disappear anytime soon, particularly for professional landscapers.
For a start, petrol machines are much more powerful, which makes for quicker work, so less time is spent lugging around heavy equipment.
Terajewicz says that heavy-duty petrol backpack blowers can reach a maximum blowing force of about 50 newtons.
The handheld Whisper Aero blower typically runs at about half that, though it can go higher.
Another big issue is runtime. Professional gardeners like to use their blowers at full throttle.
"For us, it's a little bit hard to use electric," explains Carlos Camarena, a supervisor for a California landscaping company.
Camarena's company uses electric tools where they&#x…