Agathis robusta

Queensland kauri pine

 

Agathis robusta

(C.Moore ex F.Muell.) F.M.Bailey 1883

pronounced: AG-ath-iss roh-BUSS-tuh

(Araucariaceae — the bunya family)

 

common names: Queensland kauri pine, kauri pine

native 4Agathis comes from the Greek αγαθις (agathis), a ball of thread, referring to the catkins on the female trees; robusta is Latin, robustus, of oak, firm, solid, strong.

Queensland Kauri occurs in two areas: on the Atherton Tableland, west of Cairns, and in southern Queensland on Fraser Island and around Maryborough. The mature tree photographed is growing in a Picnic Bay garden; unfortunately for photographic purposes the garden is very densely planted, of jungle-like aspect, and it was not possible to get a good photograph of the tree. The other photographs are of a young tree planted near the supermarket by the ferry terminal in Nelly Bay. This coniferous tree grows with a very straight trunk with little taper, and without buttresses, to a height of 25 - 40 m, with a trunk diameter of between 100 and 200 cm. The trunk is clear of branches for well over half its length. The smooth to flaky bark is grey-brown in colour. Woody scales from collapsing cones gather at the base of the tree.

The shoots are of two types, primary (coming from the branch) and lateral, diverging from the primary shoots. The leaves are spirally arranged on the primary shoots, and opposite to sub-opposite on the lateral shoots. Leaves are entire on petioles 3 - 10 mm long, linear to elliptic, 5 - 13 by 1 - 4 cm, and stiff; the veins are fine, longitudinal, more or less parallel. Juvenile leaves are similar, but oblong-lanceolate, acute, 6 - 7 by 1 - 2 cm, glabrous, green, shiny above and dull beneath, with the venation faint and longitudinal.

The male cones are about 4 - 10 cm long with more than 500 scales per cone, often persisting on the ground below mature trees. The female cones have slightly fewer scales per cone, and are about 8 - 10 cm in diameter. The seeds are narrowly cordate, and winged.

The tree yields a fine timber: it has an even texture, pale cream to light or pinkish brown in colour, and with a straight grain. The sapwood and heartwood are difficult to distinguish. It is commonly used for cabinet-making, turning, joinery and shelving. It has also been used successfully for making violin bellies. The wood is easy to work, and can be finished to a beautiful glossy surface, that stains and polishes well.

One of the first stands of the timber to be exploited was in the Barron River catchment, soon followed by those in the Danella State Forest. Even in the 1920s and 1930s there was much conflict between loggers and conservationists, and, although there were regulations concerning the size of trees permitted to be felled, much illegal felling took place. There were good stands on the Kirrama Range, and most of this area was logged during the second world war. Most of the timber was used in the war effort. The last stand to be logged was on the Windsor Tableland in the 1970s and 1980s. It is interesting to note that, when most of the timber was being shipped out of Cairns, and when the only reliable way of transporting it to Cairns was by rail, an upper size limit of 22 feet (6.7 m) girth (i.e. a diameter of 213 cm) had to be set on the logs so that the rail wagons would fit through the many tunnels on the Kuranda Range.

Some large trees have been measured. Some of 255 cm  DBH were recorded on Fraser Island, but were later felled. The northern population has also been heavily logged, but a tree of 137 cm DBH and 43 m tall was measured in 2002 on the Skyline Walk above Cairns. Ornamental trees are almost all from the Fraser Island population, and have grown nearly as large as the surviving wild population. A tree planted in the Albury Botanic Gardens in 1910 was measured in 2010 with a DBH of 210 cm and a height of 37 m. Calculating the age of the trees is well-nigh impossible, as in some years no growth rings are formed; but it is estimated that the oldest trees of the species would be somewhere between 200 and 300 years old.

Photoghraphed in Picnic Bay and Nelly Bay 2016
Page last updated 30th September 2018