A Blog by John Halkett

Category: Biology (Page 1 of 2)

From mattresses to psychotherapy – the amazing kapok tree

Kapok tree cluster

The tallest tree on the African continent

I remember back in the last century when I was a kid sleeping on a kapok mattress. Put your hand up if you remember doing the same.

Of course, kapok filled mattresses are a product of the kapok tree (Ceiba pentandra). A tree that when mature is an impressive sight – the tallest tree on the African continent – soaring up to as high as a 20-story building, with a huge dense spreading canopy. Not surprisingly local inhabitants usually referred to kapok read more

Madagascar baobabs – a worldwide attraction

The remnants of what was once a more extensive forest.

There are few avenues were people drive out just to see at sunset, but the Avenue of the Baobabs at Morondava draws admirers from all over the world. A dusty road half an hour’s drive north of the town of Morondava on the west coast of Madagascar passes through a stunning grove of baobabs, the remnants of what was once a more extensive forest.

The famous Avenue of the Baobabs has perhaps more than 100 trees in the grove. The species – the read more

Akatarawa giant rātā – a secret New Zealand tree treasure

Akatarawa giant rātā in thick forest near Wellington.

The now New Zealand piece of the once great southern continent Gondwanaland drafted south before the Australian eucalypts evolved, but did, and still does, host a eucalypt ancestor, the Metrosideros trees, including the pohutukawa, or New Zealand Christmas Tree, plus the Northern and Southern rātā trees. So, no eucalypts (or snakes) made it onto the New Zealand as Gondwanaland fragmented – all those millions of years ago.

Talking about rātā trees, hidden in the Akatarawa Forest, near New read more

British Columbia… awe-inspiring trees and forests

Image of BC coastal temperate forest

Back from Canada where again I was super impressed with the extent and spectacle that British Columbia’s (BC) towering trees and forests present. These forests are truly massive, covering an area of about 60 million hectares. You could drop both France and Germany into BC’s forests and they would disappear beneath the trees. Not forgetting of course that they provide habitat for an iconic population of North American large animals such as black bears, cougars, deer, coyotes and grey wolves.

Most read more

Red gums sentinels to First Fleet arrival

The only surviving eucalypts from the natural forest in the garden are two twin red gums perched up on the cliff behind the Opera House on the Bennelong lawn. No doubt they were mere saplings in 1788 when the 11 tall, wooden ships of the First Fleet arrived in Sydney. Incredibly, this Bennelong twins alone have survived so close to the city. Referring to them, Ashley Hay (Gum, 2002 Duffy & Snellgrove, Potts Point, NSW, Australia.) wrote:

The view from [its] crown began to change from the read more

Kauri and monkey puzzle tree

Magnificent planted Queensland kauri at Blackburn Cove, eastern Sydney.

I have always had a soft spot for Agathis trees. This magnificent planted Queensland kauri (Agathis robusta) is adjacent to the beach on eastern Sydney where I occasionally go for a quick swim before work. It has to be well over a hundred years old – perhaps two hundred.
Together Agathis and Araucaria form the Southern Hemisphere conifer family of trees Araucariaceae. Agathis – a genus of thirteen species is generally known as kauri, after read more

Boreal forests – it’s cold up there

Main tree species in boreal forests are conifers – pines, spruces, firs and larches – adapted to very cold climatic conditions.

Boreal forests are one of the planet’s great ecosystems. Boreal (meaning northern – they are called taiga in Russia) forest occupies the northern sub arctic zone up beyond about latitude 50 encircling the Earth at the top of the Northern Hemisphere across Russia, Scandinavia, Alaska and Canada. The boreal forest belt represents the world’s largest land-based ecosystem and act as part of the largest source and filter of freshwater on the planet.
Temperatures in these boreal read more

Northern trees disrobe for winter

Just had a working visit to Brussels, and was it cold after the emerging summer temperatures in Sydney! The locals know how to dress for one digit temperatures – I just don’t own those sort of clothes.
The deciduous broadleaf trees in Brussels and elsewhere across the northern hemisphere are also transiting into their winter wardrobe. This means shedding their cloak of leaves. This feature of northern hemisphere broadleaf trees is only occasionally seen in the southern hemisphere.

As deciduous read more

‘Dinosaur’ pine growing in Sydney


The Royal Botanic Gardens in Sydney is one of my favorite spots in the city. Recently I paid another visit and checked out the Wollemi pine. This specimen was planted as one of the first seedlings from the trees found growing in the wild.

The Wollemi pine was formally identified in 1994. It is an example of the botanical diversity and wonder of Australian trees. Discovered when bushwalker David Noble clambered down a rocky cliff into a remote canyon in the Wollemi wilderness – hence the name read more

Jungle book now available

Dr Lyndall Bull, director, Forestry Tasmania, and Cr Christine Sindt, Latrobe City, Victoria, congratulate John Halkett at the book launch at the Melbourne Outlook and Insights Conference.

Billed as the Book of the Month for September Jungle Jive: Sustaining the forests of Southeast Asia takes a constructive look at jungle conservation, arguing that implementing economic measures that value jungle trees is the way to sustain them and their biological values. The central thesis of the book is the need to inject a dose of economic realism into a subject that has been long on superlatives and emotion, but short on commercial reality.
The book sets out an argument for that in read more

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