Hello and welcome to more or less on the BBC World Service, the show that looks at the

numbers in the news and all around us. I'm Tim Halford. Coming up, there are some

statistically savvy parrots we'd like you to meet. But first, a statistic about global

impending agricultural doom was brought up in a recent episode of The Boring Talks on BBC Sounds.

The UN has warned that soils around the world are heading for depletion.

With an estimated 60 harvests left, before they're too exhausted to feed the planet.

Loyal listeners, Neil, Elizabeth and Cookie the Cat, wrote to more or less at BBC.co.uk to ask

whether they should add it to their long list of worries at the moment.

This seems like it should be the biggest issue on our radar, but we are having trouble

keeping on top of world-ending scenarios. Is it true to help us understand where this idea

that we only have 60 harvests left in our soil comes from? We turn to botanist and broadcaster James

Wong. I'm fascinated by this claim, so I've heard 60, I've also heard 30 and I've also heard

100. So I was really fascinated to see where that came from as a botanist, not a soil scientist.

So what I decided to do is contact lots of soil scientists from all over the world.

What I was really curious to figure out is how do you even go about making such a calculation?

Because it was very enormously depending on the type of soil in the world,

even the type of soil in a particular county. On top of that you have growing conditions and

climate and crops, and when it turns out is when I spoke to them, they're used words like

hardly useful. My personal favourite, almost insulting. So the one very persuaded I think is what

we're saying. Well in most situations they hadn't actually heard of the Statoidol.

So I wanted to do digging, and what you find is on the internet, people tend to repeat other

people's quotations for Statoidol. And very often it may be like three or four repetitions down

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