The iconic New Zealand Kauri is a monoecious coniferous forest specimen which grows to five metres within ten years, to a maximum of 60m height. Past the age of fifty it often achieves enormous girth. The leaves are thick, coriaceous, and lanceolate (shaped like the head of a lance). When young, foliage is pinky-green but as the tree matures its leaves move through a range of bronze to yellow greens and settle at maturity to an overall light-green.
Young trees, known as rickers (30-50 years), are light-hungry and in closed forests grow straight up on narrow boles through the canopy. As they mature the forest-shaded branches drop off. As the rickers penetrate the canopy, the upward growth of the trunk immediately ceases. At this point it divides at the top into several ascending limbs to form a flattish-topped crown which can attain up to 15m depth and a spread of up to 30m. From this point the trunk begins to establish girth.
Kauri do not flower but produce catkins (male) from September to January, and cones (female) from September to December. Once catkins release their pollen in spring, they fall. Female cones are produced from about the age of fifty, and ripen from green to reddish brown over 18 months before releasing 2cm long, single-winged seeds, and disintegrating on the tree, or falling to shatter on the ground.
Kauri are endemic with a natural habitat from Te Paki south to just below Kawhia and across to Te Puke. They favour ridges up to a maximum of 750m and much of the Coromandel, Waitakere Ranges, Little and Great Barrier Islands, and the northwest of Northland was covered in dense kauri forest where today small protected stands still remain. Agathis australis has been successfully grown as far south as Stewart Island. Kauri prefer well-drained soils with good moisture but tolerate infertile free-draining soils. They withstand wind and drought when established. The quintessential park or farm specimen tree, Kauri also grows well in stands in the company of its kin or with Totara.