That wattle, or perhaps a new plant emerging from one of its surviving seeds (for wattle seeds are as tough as nails), is acclaimed as the first flowering plant to resume flowering in Hiroshima's bomb-ravaged zone. No wonder, then, that a wattle is famous in Hiroshima as a poignant symbol of hope of regeneration. Back to that legendary acacia in just a few luminous sentences.

Sir Henry Wotton was spot-on, about human diplomats, when he said that "An ambassador is someone sent abroad to lie for his country". But it is a different kettle of flowers and foliage when the ambassadors are cross-my-heart-and-hope-to-die utterly truthful botanical ones, like our Wollemi pines, now (as much-reported here) representing us around the world.

And loyal readers will know that we have been nattering here about the noble, ambassadorial eucalypt at Hiroshima Castle. It survived the 1945 blast (even though only 740 metres from its epicentre) and is alive and well (see our recent picture), although a little propped-up these days, like a venerable old gentleman with a walking stick.

Some readers, including Warwick and Pat Wright, have been kind enough to send us their photographs taken in Hiroshima of this dear ambassador of ours. It is as well an ambassador for the toughness of its species, because as well as surviving the blast that left it blackened and ravaged it has since survived some bough-snapping typhoons.

"We knew our flora was adapted to bushfire – but nuclear blasts?" Warwick Wright marvels.

The Wrights (they are both guides at the Australian National Botanic Gardens and Pat is a considerable acacia authority) testify that they were in Hiroshima to visit a band called the Hiroshima Acacia Appreciation Society. We pricked up our ears at this and wondered what this evocatively named association was all about.

The Wrights explain that the society is so appreciative of acacias because it was an acacia, a survivor of what had been a whole avenue of them at the university, that was the first plant to flower at Hiroshima after the horror of 1945.

"Since 1992," Warwick Wright explains, "the Hiroshima Acacia Appreciation Circle has sent 1000 yellow ribbons each year to the ANBG … as a symbol of friendship, hope and renewal (and, we assume, forgiveness)."

Yes, a Gardens spokeswoman adds that members of the Acacia Appreciation Society have twice travelled from Hiroshima to visit the Australian National Botanic Gardens to celebrate Wattle Day. Every year since their first visit in the 1990s the Gardens has received 1000 yellow ribbons as a gesture of friendship and to convey the message: "To wish you a happy life with fulfilled dreams. When a wattle starts to bloom, make a wish and your wish will come true".

Visitors to the Australian National Botanic Gardens are encouraged to wear one of the ribbons during their visit to their Gardens and then to take it home to attach to a favourite tree.

Poignantly, appropriately, the 1000 yellow ribbons are sent from Japan to the Gardens at exactly this time of the year.

"I'm expecting the next batch right now," the Gardens spokeswoman tells us.

While with wattles the most lurid wattle of them all, the controversial Cootamundra wattle (Acacia baileyana) is one of those presently illuminating our bushland. Its colour is calling out (shrieking, really) to commuters commuting past bushland. There is continuous debate about it, with a recent impassioned letter to the editor deploring the way in which ACT governments and environmentalists continue to kill it because it is so invasive while not being native to our local bushland. Its defenders want it left alone because it imparts such colour to their drab lives and to otherwise drab (to some) bushland.

This columnist's mind is slightly ajar on this issue, while noting that for some of us the worst thing about the species is that its flowers' shrieking hue of yellow is so ghastly. Once upon a time, some years ago, we decided to seek expert advice on this and so (using magic and time travel) brought Oscar Wilde to Canberra to take him for a walk in some local bushland. It was Wilde, remember, always an aesthete, who chose to die rather than go on living on his deathbed in a bedroom with walls papered with a design that offended him.

"This is awful. One of us has to go!" he moaned, looking at the wallpaper, moments later choosing death rather than further exposure to barbaric tastelessness.

Here in Canberra as our consultant we took him on a walk in some ACT bushland where every plant, native to the place, was aesthetically in grey-green tune. Wilde purred with delight.

But then, rounding a corner, we came (as I had intended) upon a flowering Cootamundra Wattle. Wilde recoiled, ashen-faced, and then was quite sick into a clump of Stypandra glauca.

We didn't have selfies in those days but I reported Wilde's horrified reaction to gifted illustrator lan Sharpe and he captured Wilde's horror exactly as it had been.

"Ian, this is awful. Can we go somewhere else?" I remember Wilde pleading.

And so I took him to a football match where, understandably, he was made ill again this time by the vile green of the Raiders jerseys.

Rejoice!

One hundred years ago today Melbourne's Table Talk, fed up with wartime gloom, sounded a trumpet blast of optimism.

"The 'cheer up' policy, will be resounding through Melbourne in the spring.

"Twelve months ago the croakers said, 'This war is frightful; we are in for a bad time.' Well, time has flown, and there is no universal slump. The croakers are still mooning around .. but the saner people have begun to snap their fingers in the long faces of the pessimists.

"And they have reason on their side. Things are not bad and in a few months they will be good. The drought is a thing of the past, the menace of a possible German, invasion of Australia has long been banished with the destruction of the Kaiser's Pacific fleet. Shipping trade with almost every part of the world has been restored, millions and millions of borrowed money is being disseminated through the community in the shape of soldiers' pay and army contracts; the local war loan is a success and gives a high rate of interest to widows and the general public, manufacture is on the increase, wages are liberal, our Australian army is the highest paid on earth and has earned undying fame, money is plentiful, sheep are getting fat, corn is springing, orchards are in bloom, the sun is shining, the Kaiser has gone mad and the warriors of freedom call a trumpet blast of glory.

"Buck up, then, old dismal dog!"