"The first Cavendish banana came from a man called Paxton in Chatsworth Garden district in Derbyshire, England. Obviously grown in a greenhouse. I am a wealth of knowledge."

That was it.

I texted back: "Cultivated bananas are parthenocarpic."

Thus ended that little exchange. She said later the text had been prompted by an English TV show about Chatsworth Garden and Paxton. She wants to go there. I told her to stop drinking before the sun's last rays drop beyond the horizon.

Now I had no idea the word parthenocarpic even existed until her text, which arrived as I was sitting in front of the computer working. In a couple of seconds I Googled the words banana and Paxton, came up with Wikipedia, scrolled down for something random to send in reply and settled on "Cultivated bananas are parthenocarpic".

It was a zen-enough response to stop the flow of other random text messages.

But it got me thinking, 30 minutes later, after a wild dive into the internet that began with a search for the meaning of "parthenocarpic", included an update on the existential threat facing bananas, and ended, almost inevitably, with Donald Trump.

Somewhere within that 30 minutes all thought of the work I was doing was abandoned, which is the way of the internet. But it was entertaining, and enlightening.

To save you the trouble, parthenocarpic means the induced production of fruit without fertilisation of ovules, or at least that's what Wikipedia came up with when I went looking for a definition of the word. As for what an ovule is, or whether bananas taste better because they're free of fertilisation by ovule, I have no idea. But there are nearly 20 million smartphones in Australia today so feel free to find answers to the above at your leisure, or not. In a world with a gazillion pieces of information at our fingerprints I think it is useful to know where to draw the line on knowledge. The ovule seems to be it for me.

But back to bananas.

There's been so much happening in the world this year - convulsions in America, the Brexit madness in Britain, climate change activism, the Hong Kong protests, the Vatican bishops' conference in response to the child sexual abuse crisis, Cardinal George Pell's jail sentence, the Christchurch massacre, the Morrison government's unexpected re-election, India's sudden shift in Kashmir, the Duchess of Cambridge's new hairdo - that it's easy to overlook the lesser dramas, like the possible end of bananas as we know them.

There's a useful Australian government Department of Agriculture website reached in just a few Google steps from parthenocarpic to banana, to Cavendish, to "threats to Cavendish", Panama disease and on to the Department of Agriculture's information page on "Panama Disease Race 4".

It includes the dire warning: "If the disease were to spread beyond its current distribution in Australia, it would devastate Australia's banana industry."

A bananapocalypse, in other words, requiring a determined community response.

We've had a few warnings about Australian banana shortages in the past, and what happens when Australians lose their banana smoothies and banana bread.

In 2006 Cyclone Larry destroyed nearly 90 per cent of Australia's banana crop, pushing the cost of survivors up by 500 per cent.

In 2011 it was floods in Queensland and NSW that cut banana supplies down to 15 per cent, leaving people queueing for rationed bananas at $14 a kilogram. I wrote a column back then about paying $3.20 for a single banana at home, only days after gorging on cheap bananas while in Iceland for 10 days. And they don't grow bananas in Iceland.

The existential threat facing 80 per cent of the world's bananas flows from the success of the Cavendish banana, developed - as my friend confirmed in the text that started all this - by Sir Joseph Paxton in the greenhouses of Chatsworth House after a supply of bananas was sent to England from Mauritius.

Paxton sent some of his Cavendish bananas back to the Pacific in the mid-1800s. The Cavendish came to dominate world banana supplies in the 1950s after Panama Disease wiped out the Gros Michel variety. Now a "Race 4" version of Panama Disease is doing for the Cavendish what an earlier "race" did to the Gros Michel.

To cut the Department of Agriculture's warning down to something you can do at home - be on the lookout for banana plants with yellow leaves, check the website for other information and ring the Exotic Plant Pest Hotline on 1800 084 881 if, as the department advises, you "see anything unusual" banana-wise.

I like bananas a lot. This is serious.

Anyway, I don't know how I ended up with Donald Trump impeachment updates while researching banana disease, but as I flicked from one breathless "breaking news" grab to another, or scrolled down lengthy pieces heavy with the words "constitutional crisis", I thought back to 1974 and Richard Nixon's stand-off with the US government's legislative arm over Watergate.

I was 14 then. I heard the news about his resignation in August that year via someone's radio, while sitting in a campervan at Tennant Creek in the Northern Territory. News of the unfolding drama that played out in 1974 dominated Australian media, but not like the minute-by-minute Trump updates you can drown in today when you go online.

Nixon's downfall had a certain tragic element to it. Bill Clinton's impeachment over a sex scandal had a fevered abandon about it. But moves on Trump feel much more high stakes. A powerful man extolling his "great and unmatched wisdom" won't be taking any prisoners if he's cornered.