The mature lime trees along Ladies Mile are testament to how long Gordon Milward has worked on the Downs.

When he planted them in the 1970s, they were small saplings – now they loom over the road in all their glory, just some of the 3,000 trees that as Downs Ranger he has responsibility for.

That responsibility will soon pass to a new Downs Ranger, Charlie Denyard, but not before Gordon, 59, who lives in Portishead, has passed on the knowledge that he has acquired in his 40 years spent working on the Downs.

"It's such a large area, so diverse," he said, as we walked across the Downs from his office in what's known as 'the Pound', the area by the stubby stone ventilation shaft at the top of Pembroke Road.

As we walk, the sound of bagpipes fills the air. Gordon hardly bats an eyelid. "As long as the noise isn't bothering anyone," he says with a smile.

Where many of us see nothing but grass and trees as we stroll across the Downs, which encompasses everything from wildflower meadows to football pitches, Gordon's keen eye sees everything: tree branches that need chopping, grass and hedges that need cutting, seats that need replacing.

Gordon is a council employee, but everything that he and his team of seven workers do is reported to the Downs Committee, which has managed the Downs since the passing in 1861 of the Clifton and Durdham Downs Act.

The Downs are still administered by the Downs Committee, whose members are appointed in equal numbers by Bristol City Council and the Society of Merchant Venturers.

At Gordon's last meeting earlier this month, held in the Mansion House, the official residence of the Lord Mayor, the Downs Committee presented the outgoing Downs Ranger with a Bristol Blue Glass plaque and a framed map of the Downs from 1906.

Gordon says he will miss the work that he does to maintain the 400 acres of the Downs, and that he will miss the people that he works with. But he is also looking forward to his retirement, the first two months of which he will spend caravaning around Scotland with his wife Jean.

What he will not miss is constantly having to remind visitors to the Downs of its particular bye-laws, including no parking, no cycling and no barbecues, things that over the years Gordon has found are being increasingly flouted.

Enforcing the bye-laws and litter-picking are two areas of the job that aren't so much fun, but Gordon said that it is always a pleasure to see a job well done.

"We have just done some scrub clearance and scrub reduction on the Circular Road," Gordon says, sipping a coffee in the Downs Tea Rooms, still a dilapidated Victorian toilet when he begun working on the Downs in 1969.

"It has been good to see it done, see it happening and see it completed. When you go down there now, to see it used by a lot more people is great. When it was overgrown, it was more difficult for people to use, and now they can walk there, well that's certainly a job well done."

With the many events taking place on the Downs throughout the year, from firework displays to Funderworld – the travelling theme park currently using the area at the top of Whiteladies Road – one of the team's biggest jobs is "site reinstation" – getting the area back to normal after a big event has taken place.

Gordon said that the worst state the Downs has been in during his four decades working there was after the six-week long Bristol 600 event in 1973, when it took almost two years to get the area of the Downs known as the Seven Sisters, between Westbury Road and Stoke Road, back into good shape.

Gordon always keenly anticipates the changing of the seasons, and spring is one of his favourite times of the year.

"I love seeing the flowers coming through, the new life. It's always a clean time of year I think because everything is new.

"Each area of the Downs is different, with its own character, but a lot of the time I can't enjoy it as I'm always looking for problems.

"When I'm on the Downs, I try to walk.

"You can see so much more when walking, and I'm usually out two or three days a week.

"I can see the trees that I've planted, the hedges that I've managed, the wildflower meadows that I have tended, and I can think to myself, job well done."