About Me

My photo
Canberra-based naturalist, conservationist, educator since 1980. I’m passionate about the natural world (especially the southern hemisphere), and trying to understand it and to share such understandings. To that aim I’ve written several books (most recently 'Birds in Their Habitats' and 'Australian Bird Names; origins and meanings'), run tours all over Australia, and for the last decade to South America, done a lot of ABC radio work, chaired a government environmental advisory committee and taught many adult education classes – and of course presented this blog, since 2012. I am the recipient of the Australian Natural History Medallion, the Australian Plants Award and most recently a Medal of the Order of Australia for ‘services to conservation and the environment’. I live happily in suburban Duffy with my partner Louise surrounded by a dense native garden and lots of birds.

Thursday, 22 March 2018

Conifers of the South; #2 the kauris, bunyas and podocarps

This is the second and final part of a series which began here; in a broader sense it's part of an intermittent series on 'favourite trees', links to which can be found in part 1. It's probably worth reading part 1 before you read this, as I won't repeat background material on conifers from there.

Today is about the other two conifer families found mostly in the Southern Hemisphere; indeed we often refer to them as Gondwanan, but in this case we'd be wrong to deduce past distributions from their current ones, or assume that they must have arisen in the south because they primarily grow there now. As previously discussed, the families are all very old and were once scattered throughout the world - today's 'Gondwanan' families only survived in the south. Probably the better-known of the families is Araucariaceae, found mostly in New Caledonia, with species in Australia, Malesia (Indonesia, Philippines, New Guinea and peninsular Malaysia), New Zealand, the Pacific and South America.
Bull Kauris Agathis microstachya Lake Barrine, north Queensland.
Like nearly all members of the family this is a rainforest tree, which is a bit of mystery
given the usual narrative of conifers retreating to high latitudes and altitudes in the
face of the spread of flowering plants.
Bull Kauris are found only on the Atherton Tableland, inland from Cairns, but there are two other Australian Agathis species, including Blue Kauri A. atropurpurea with an equally limited range in north Queensland coastal ranges, and Queensland Kauri A. robusta, which has a curious two-part distribution. One population is also on the Atherton Tableland, the other well to the south and on coastal sands on and near Fraser Island.
Queensland Kauri, growing as an emergent on Fraser Island.
Queensland Kauri, Fraser Island; detail of the beautiful bark.
Like all of the family in Australia, this species was heavily logged in earlier times and, while not as threatened
as the other two Australian species, it is hard to find big trees.
Of the 21 living Agathis there are half a dozen Malesian species, mostly from Borneo.
Agathis kinabaluensis Crocker Range, Sabah, Borneo.
This tree is limited to montane rainforest on and near Mount Kinabalu.
Araucaria, the type genus of the family, has around 20 species, 14 of which are endemic to New Caledonia. However it was named from one of the two South American species, A. araucana, from central Chile and nearby Argentina. The name was coined to honour the people (a sub-group of Mapuche) who inhabit the area where the tree is found. The English name of this species is Monkey Puzzle Pine, for the wickedly spiked crowded tough sharp leaves which cover most of the plant.

Monkey Puzzle Pine, Conguillio NP, Chile.
Photo courtesy Wikipedia.
Two mainland Australian Araucaria species are well-known. Bunya Pines A. bidwillii were once widespread in south-east Queensland, but logging and general clearing have fragmented the distribution to a few mountain refuges, especially the Bunya Mountains. You can find more about the place of the pines in those mountains, and their cultural significance, in that posting link.

Emergent Bunya Pines, Bunya Mountains NP.
Here too the pines grow as rainforest emergents - indeed they dominate the forest.

Trunk of an old Bunya Pine. There are stories that the 'chop' marks were the work of
indigenous Bunya nut harvesters, but they seem to be just stories.

Try to ignore the hat and trousers - this photo was taken a VERY long time ago....
The seeds of this enormous cone were greatly valued by local people in pre-European times,
and even by those further away who gathered in the mountains when the cones were ripe.
Another Araucaria also grows in the Bunyas, though Hoop Pine A. cunninghamii has a much wider distribution, from the north of New South Wales, through Queensland to New Guinea. It is readily distinguished from the Bunya Pines, including in its very small cones.
Hoop Pines, Bunya Mountains (above) and Conway NP, tropical Queensland (below).
See how much more 'spiky' is the crown outline compared with the dome of the Bunya Pine.

Hoop Pine trunk, Bunya Mountains, with the 'hoops' from which its name derived.
Another well-known Araucaria is the Norfolk Island Pine, A. heterophylla, endemic to the island between Australia and New Zealand, but planted throughout a lot of the world as a salt-hardy and decorative tree.

Norfolk Island Pine, Culburra, south coast New South Wales.

Norfolk Island Pine (with Western Corella), Augusta, south-west Western Australia.
The family Podocarpaceae is much larger, with some 100 species in 20 genera, though the majority of those are in the genus Podocarpus. It is centred on Australasia, with other concentrations in Malesia and South America. A couple are found in Africa, and some extend into mainland Asia. One important characteristic is the production of a female cone which resembles a berry, coloured and sweetened to encourage animals to distribute the seed.

Mountain Plum Pine Podocarpus lawrencei 'berry', with the green seed attached;
Namadgi National Park, above Canberra. The name means 'foot fruit'.
Pollen-bearing male cones, Mount Ginini, Namadgi NP.
Many species of the genus are rainforest trees, but Mountain Plum Pine, from the high mountains of south-eastern Australia, lives in the alpine and sub-alpine zones, sprawling low over rocks and surviving under the snow in winter. During past glaciations it was left behind by retreating forests and adapted to the new cold and dry regime. It provides very important animal habitat, including to the Endangered Mountain Pygmy Possum Burramys parvus.
Mountain Plum Pine forming a mat over granite boulders, Kosciuszko NP, New South Wales.
 More typical is the so-called Brown Pine P. elatus, of east coast rainforests. 
Brown Pine, Australian National Botanic Gardens, Canberra.
The berries will turn purple when the seeds are ready for birds to harvest.
Here is a South American member of the genus; MaƱio Macho Podocarpus nubigenus grows further south than any other member of the family, down to 53 degrees south in Chile. 
Podocarpus nubigenus at Puerto Aiguierre in the Chonos Archipelago of southern Chile.
Perhaps the best-known Australian family member is a single-species genus from Tasmania, Huon Pine Lagarostrobos franklinii, famed especially for its glorious timber, much prized by craftspeople. It is now illegal to cut living trees, but fallen ones - which last for centuries - may be collected under strict licensing agreements.

Huon Pine, mature tree overhanging the Huon River (fittingly) above,
and young trees below along the nearby Picton River.
Another Tasmanian endemic Podocarp is the Celery-top Pine Phyllocladus aspleniifolius; other members of the genus are found in New Zealand and Malesia. Its foliage is not at all reminiscent of that of most conifers.

Celery-top Pine foliage, Mount Field NP, southern Tasmania.
Blue Mountains Pine is a dwarf species, with a tiny range and a remarkable habitat. It lives only in a small area of the high Blue Mountains, within the splash zone of sandstone waterfalls. It is the only member of its genus.

Blue Mountains Pine Pherosphaera (formerly Microstrobus) fitzgeraldii, here growing apparently
happily in an artificial waterfall in the National Botanic Gardens, Canberra.
And with that we'll wrap up this brief tour of the southern conifers, with the hope that you were able to find something of interest here.

(And remember that you can get a reminder when the next post appears by putting your email address in the Follow by Email box in the top right of this screen.
And I'd love to receive your comments - it's easy and you don't need to sign in!)

No comments: