Artist, writer and sculptor;

Born: December 31, 1921; Died: May 15, 2012.

George Wyllie, who has died aged 90, was an artist who will be forever associated in the public's mind with his social sculptures – best-known of which were probably The Straw Locomotive (1987) and The Paper Boat (1989-90).

But, when asked in his last ever interview late last year what his favourite was among the thousands of artworks he had created during a five-decade long career, he declared: "I like my little spire. My little vertical wand responding to the earth and the air."

As a young sailor, in the Royal Navy, Wyllie walked among the charred ruins of the city of Hiroshima with some shipmates, and it sparked a lifelong concern for environmental issues.

His subsequent friendship many years later with the German conceptual artist Joseph Beuys, founder of the German Green Party, cemented his approach to creating all his art.

Wyllie erected his spires in the most unlikely, yet apposite, places. Locations include The Lecht (Cosmic Reach) and the site of the old Rottenrow Maternity Hospital in Glasgow (Monument to Maternity). He even had his own portable spire, which he wore slung over his back like a rifle.

In 1990, he placed a spire on Gruinard in the Western Isles to mark its official "decontamination" from anthrax after 50 years. His plaque at the bottom read: "For air, stone and the equilibrium of understanding. Welcome back Gruinard."

George Ralston Wyllie was born to Andy and Harriet (Harry) Wyllie in Shettleston, Glasgow. He was named after his grandfather and for many years his family and friends called him Ralston.

Encouraged by their mother, Wyllie and his younger brother Banks were taught how to play the ukelele, how to draw and paint and how to dance.

"People liked 'our Harry'", Wyllie said many years later in a recording made for the British Library's Artist Lives series. "She was full of vim and zest and I was her bright-eyed boy."

The family moved to the Craigton area of Glasgow when he was still a little boy and he grew up in the shadow of the shipyards. His father was a rate fixer for a machine tool engineering company on the Clyde and the young George was much enamoured of cranes and model aeroplanes.

While at school, he was offered a job in the crane-building department of Sir William Arrol & Co – on the strength of his drawings of model planes and cranes he had built in his spare time. His father, however, forbade him from taking the job on the grounds it was an "airy job" and he would be vulnerable should another slump in the economy happen.

Instead, his first job was a "safe" one, designing man-holes in the Post Office engineering department. He escaped this safe job by joining the Royal Navy. He went to war in 1942 and it was during a spell of leave that he met his wife Daphne at a dance in Gosport. Their lifelong romance lasted until her death in 2004.

Wyllie remained at sea until 1946 and when his war ended, he sat a civil service exam and became a customs and excise officer in Greenock. A promotion saw him moved to Northern Ireland, where he worked on the land boundary patrol across the border.

The family, which by 1954 consisted of daughters Louise and Elaine, returned to Scotland and the Wyllies set up house in Gourock.

Music had always been in the background for Wyllie and he played double bass with his band around pubs and clubs in the area. In 1965, he decided it was "time for art", which had always been "an extra thing" in his life.

He often joked that being accepted by Glasgow School of Art's jazz band was the closest he got to an art training but, despite the humour in his work, Wyllie was deadly serious about schooling himself and finding his metier.

He attended welding classes in Greenock and one of his first sculptures from this period was bought by Ferguson's Shipyard. It seems commonplace now, but he recycled materials in a way which no artist had done before.

A pile of old car bumpers became a series of fish, for example, many of which have come to light during a recent search for a forthcoming retrospective of his work.

He left the customs service in 1979, at the age of 58, and entered into a long career as an artist, writer and sculptor. He described himself as a "scul?tor", because he claimed the question mark was too important to be left to the end.

In the 1980s, through the late Barbara Grigor – a champion of many a Scottish artist – Wyllie met the American kinetic artist, George Rickey, who invited him to work with him in America. He later described this experience as a "great art release". He was also hugely influenced by Beuys after meeting him through Edinburgh gallery owner, Richard Demarco.

Wyllie's award-winning play about the iniquities of the world banking system, A Day Down A Goldmine, was produced several times throughout the 1980s. The two-handed play featured Wyllie as a character called His Assistant (Goldbunnet) alongside acclaimed actors such as Russell Hunter and Bill Paterson.

In 1987, he attracted international attention with his Straw Locomotive, which hung from the Finnieston crane in Glasgow before being burned in Springburn, where trains had been manufactured, in a Viking-style funeral.

Two years later, his Paper Boat was seen by millions as it sailed around the world from Glasgow to New York and back to Scotland. It even made it onto the front page of the Wall Street Journal when it berthed at the World Financial Centre in New York in 1990. Wyllie even added a raft of moral quotations from Adam Smith specifically for its US trip.

Wyllie was creating work well into his 80s but, in recent years, a combination of factors – including failing eyesight and mobility problems – led to a series of falls and he moved out of his Gourock eyrie overlooking the Firth of Clyde and into The Mariners, a nearby care home for retired sailors.

Faced with the twin challenges of what to do with their father's treasure trove of artwork and how to celebrate his legacy, Wyllie's daughters Louise Wyllie and Elaine Aitken set up The Friends of George Wyllie in 2011.

Friends, or "chums", of George included his old friends, artists Dawson and Liz Murray, Neil Baxter of the Scottish architecture body, the RIAS, and filmmaker Murray Grigor, whose award-winning 1990 film about Wyllie, The Why?s Man, has recently been re-released on DVD.

This year, 2012, sees a year-long celebration of Wyllie's artistic legacy under the banner The Whysman Festival. Just last week, it was announced his work would inspire a new generation, thanks to a major award from Creative Scotland.

Knowing that so much effort and work were going into celebrating and promoting his work gave Wyllie no end of pleasure at the end of his life.

As his daughter Louise said just after he died in hospital in Greenock on Tuesday night: "It was as though midnight had come and it was time to leave."

George Wyllie was predeceased by his wife Daphne and his younger brother Banks. He is survived by daughters Louise Wyllie and Elaine Aitken, as well as grandsons Calvin and Lewis, and grand-daughter Jennifer.