What Do You Know: It DOES Grow On Trees ....

Wiki:

The spaghetti tree is a fictitious tree and the subject of a 3-minute spoof report on the Swiss spaghetti harvest beside Lake Lugano broadcast by the BBC current affairs programme Panorama.

The report was first produced as an April Fools' Day joke in 1957, reporting on the bumper spaghetti harvest in Switzerland, resulting from the mild winter and "virtual disappearance of the spaghetti weevil." Footage of the traditional "Harvest Festival" was aired as well as discussion of the breeding necessary for the development of a strain that produced the perfect length.

The report was given additional plausibility by the voiceover by respected broadcaster Richard Dimbleby. Pasta was not an everyday food in 1950s Britain, and was known mainly from tinned spaghetti in tomato sauce. It was considered by many to be an exotic delicacy. Parts of the documentary were filmed at the (now closed) Pasta Foods factory on London Road, St Albans in Hertfordshire, and other parts at a hotel in Castiglione, Switzerland.

Panorama cameraman Charles de Jaeger dreamed up the report after remembering how teachers at his school in Austria used to tease his classmates for being so stupid that they would believe it if they were told spaghetti grew on trees.

An estimated 8 million people watched the programme on April 1, and hundreds phoned in the following day to question the authenticity of the story, or ask for more information about spaghetti cultivation and how they could grow their own spaghetti trees. The BBC reportedly told them to "place a sprig of spaghetti in a tin of tomato sauce and hope for the best".

At the time of the broadcast there were 7 million homes in Britain with television sets, out of a total of 15.8 million homes.

In the obituary for de Jaeger, who died in London on 19 May 2000, which was published in The Independent Newspaper, Ian Jacob the then Director-General of the BBC is quoted as having said to Leonard Miall, Head of Television Talks 1954-61:

"When I saw that item, I said to my wife, 'I don't think spaghetti grows on trees', so we'd looked it up in Encyclopædia Britannica. Do you know, Miall, Encyclopædia Britannica doesn't even mention spaghetti."